U.S. patent application number 11/247361 was filed with the patent office on 2006-04-06 for substituted 2-phenyl benzofurans as estrogenic agents.
This patent application is currently assigned to Wyeth. Invention is credited to Leo M. Albert, Michael D. Collini, Heather A. Harris, David H. Kaufman, James C. JR. Keith, Christopher P. Miller, Robert L. Morris, Robert R. JR. Singhaus, John W. Ullrich, Rayomand J. Unwalla.
Application Number | 20060074128 11/247361 |
Document ID | / |
Family ID | 23338402 |
Filed Date | 2006-04-06 |
United States Patent
Application |
20060074128 |
Kind Code |
A1 |
Miller; Christopher P. ; et
al. |
April 6, 2006 |
Substituted 2-phenyl benzofurans as estrogenic agents
Abstract
This invention provides estrogen receptor modulators of formula
1, having the structure ##STR1## wherein R, R', A, A', X, Y, and Y
are as defined in the specification, or a pharmaceutically
acceptable salt thereof.
Inventors: |
Miller; Christopher P.;
(Wayne, PA) ; Collini; Michael D.; (Clifton
Heights, PA) ; Kaufman; David H.; (Berwyn, PA)
; Morris; Robert L.; (Wayne, PA) ; Singhaus;
Robert R. JR.; (Blandon, PA) ; Ullrich; John W.;
(Exton, PA) ; Harris; Heather A.; (Phoenixville,
PA) ; Keith; James C. JR.; (Andover, MA) ;
Albert; Leo M.; (Burlington, MA) ; Unwalla; Rayomand
J.; (Eagleville, PA) |
Correspondence
Address: |
COZEN O' CONNOR, P. C.
1900 MARKET STREET
PHILADELPHIA
PA
19103-3508
US
|
Assignee: |
Wyeth
Madison
NJ
07940
|
Family ID: |
23338402 |
Appl. No.: |
11/247361 |
Filed: |
October 11, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10828970 |
Apr 21, 2004 |
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11247361 |
Oct 11, 2005 |
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10320207 |
Dec 16, 2002 |
6774248 |
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10828970 |
Apr 21, 2004 |
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60341638 |
Dec 18, 2001 |
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Current U.S.
Class: |
514/469 ;
549/469 |
Current CPC
Class: |
A61P 7/00 20180101; A61P
9/12 20180101; A61P 13/00 20180101; A61P 13/02 20180101; A61P 3/10
20180101; A61P 9/00 20180101; A61P 29/00 20180101; A61P 9/10
20180101; A61P 3/06 20180101; A61P 15/18 20180101; A61P 19/02
20180101; A61P 25/22 20180101; A61P 35/00 20180101; A61P 37/06
20180101; A61P 11/06 20180101; A61P 25/28 20180101; A61P 17/00
20180101; A61P 25/00 20180101; C07D 413/04 20130101; A61P 15/00
20180101; A61P 1/04 20180101; A61P 17/02 20180101; A61P 5/30
20180101; A61P 39/06 20180101; A61P 13/10 20180101; A61P 9/14
20180101; A61P 3/00 20180101; C07D 405/06 20130101; C07D 307/80
20130101; A61P 11/00 20180101; A61P 1/02 20180101; A61P 5/00
20180101; A61P 1/00 20180101; A61P 27/02 20180101; A61P 13/08
20180101; A61P 17/06 20180101 |
Class at
Publication: |
514/469 ;
549/469 |
International
Class: |
A61K 31/343 20060101
A61K031/343; C07D 307/87 20060101 C07D307/87 |
Claims
1-15. (canceled)
16. A method of treating or inhibiting arthritis in a mammal in
need thereof, which comprises providing to said mammal an effective
amount of a compound of formula I, having the structure ##STR26##
wherein P and P' are each, independently, hydrogen, alkyl of 1-6
carbon atoms, or acyl of 2-7 carbon atoms; X is hydrogen or
halogen; R is hydrogen, alkyl of 1-6 carbon atoms, halogen, --CN,
or --CHO; R' is alkoxy of 1-6 carbon atoms, or cyanoalkyl having
1-6 carbon atoms in the alkyl moiety; or a pharmaceutically
acceptable salt thereof.
17. The method according to claim 16, wherein the arthritis is
rheumatoid arthritis, osteoarthritis or spondyloarthropathies.
18. A method of treating or inhibiting joint swelling or erosion;
or treating or inhibiting joint damage secondary to arthroscopic or
surgical procedures in a mammal in need thereof, which comprises
providing to said mammal an effective amount of a compound of
formula I, having the structure ##STR27## wherein P and P' are
each, independently, hydrogen, alkyl of 1-6 carbon atoms, or acyl
of 2-7 carbon atoms; X is hydrogen or halogen; R is hydrogen, alkyl
of 1-6 carbon atoms, halogen, --CN, or --CHO; R' is alkoxy of 1-6
carbon atoms, or cyanoalkyl having 1-6 carbon atoms in the alkyl
moiety; or a pharmaceutically acceptable salt thereof.
19-22. (canceled)
Description
[0001] This application claims priority from copending provisional
application Ser. No. 60/341,638, filed Dec. 18, 2001, the entire
disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] This invention relates to substituted 2-phenyl benzofurans,
which are useful as estrogenic agents.
[0003] The pleiotropic effects of estrogens in mammalian tissues
have been well documented, and it is now appreciated that estrogens
affect many organ systems [Mendelsohn and Karas, New England
Journal of Medicine 340: 1801-1811 (1999), Epperson, et al.,
Psychosomatic Medicine 61: 676-697 (1999), Crandall, Journal of
Womens Health & Gender Based. Medicine 8: 1155-1166 (1999),
Monk and Brodaty, Dementia & Geriatric Cognitive Disorders 11:
1-10 (2000), Hurm and Macrae, Journal of Cerebral Blood Flow &
Metabolism 20: 631-652 (2000), Calvin, Maturitas 34: 195-210
(2000), Finking, et al., Zeitschrift fur Kardiologie 89: 442-453
(2000), Brincat, Maturitas 35: 107-117 (2000), Al-Azzawi,
Postgraduate Medical Journal 77: 292-304 (2001)]. Estrogens can
exert effects on tissues in several ways, and the most well
characterized mechanism of action is their interaction with
estrogen receptors leading to alterations in gene transcription.
Estrogen receptors are ligand-activated transcription factors and
belong to the nuclear hormone receptor superfamily. Other members
of this family include the progesterone, androgen, glucocorticoid
and mineralocorticoid receptors. Upon binding ligand, these
receptors dimerize and can activate gene transcription either by
directly binding to specific sequences on DNA (known as response
elements) or by interacting with other transcription factors (such
as AP1), which in turn bind directly to specific DNA sequences
]Moggs and Orphanides, EMBO Reports 2: 775-781 (2001), Hall, et
al., Journal of Biological Chemistry 276: 36869-36872 (2001),
McDonnell, Principles Of Molecular Regulation. p351-361(2000))]. A
class of "coregulatory" proteins can also interact with the
ligand-bounde receptor and further modulate its transcriptional
activity [McKenna, et al., Endocrine Reviews 20: 321-344 (1999)].
It has also been shown that estrogen receptors can suppress
NF.kappa.B-mediated transcription in both a ligand-dependent and
independent manner [Quaedackers, et al., Endocrinology 142:
1156-1166 (2001), Bhat, et al., Journal of Steroid Biochemistry
& Molecular Biology 67: 233-240 (1998), Petzer, et al.,
Biochemical & Biophysical Research Communications 286: 1153-7
(2001)].
[0004] Estrogen receptors can also be activated by phosphorylation.
This phosphorylation is mediated by growth, factors such as EGF and
causes changes in gene transcription in the absence of ligand
(Moggs and Orphanides, EMBO Reports 2: 775-781 (2001), Hall, et
al., Journal of Biological Chemistry 276: 36869-36872 (2001)].
[0005] A less well-characterized means by which estrogens can
affect cells is through a so-called membrane receptor. The
existence of such a receptor is controversial, but it has been well
documented that estrogens can elicit very rapid non-genomic
responses from cells. The molecular entity responsible for
transducing these effects has not been definitively isolated, but
there is evidence to suggest it is at least related to the nuclear
forms of the estrogen receptors [Levin, Journal of Applied
Physiology 91: 1860-1867 (2001), Levin, Trends in Endocrinology
& Metabolism 10: 374-377 (1999)].
[0006] Two estrogen receptors have been discovered to date. The
first estrogen receptor was cloned about 15 years ago and is now
referred to as ER.alpha. [Green, et al., Nature 320: 134-9 (1986)].
The second form of the estrogen receptor was found comparatively
recently and is called ER.beta. [Kuiper, et al., Proceedings of the
National Academy of Sciences of the United States of America 93:
5925-5930 (1996)]. Early work on ER.beta. focused on defining its
affinity for a variety of ligands and indeed, some differences with
ER.alpha. were seen. The Ussue distribution of ER.beta. has been
well mapped in the rodent and it is not coincident with ER.alpha..
Tissues such as the mouse and rat uterus express predominantly
ER.alpha., whereas the mouse and rat, lung express predominantly
ER.beta. [Couse, et al., Endocrinology 138: 4613-4621 (1997),
Kuiper, et al., Endocrinology 138: 863-870 (1997)]. Even within the
same organ, the distribution of ER.alpha. and ER.beta. can be
compartmentalized. For example, in the mouse ovary, ER.beta. is
highly expressed in the granulosa cells and ER.alpha. is restricted
to the thecal and stromal cells [Sar and Welsch, Endocrinology 140:
963-971 (1999), Fitzpatrick, et al., Endocrinology 140: 2581-2591
(1999)]. However, there are examples where the receptors are
coexpressed and there is evidence from in vitro studies that
ER.alpha. and ER.beta. can form heterodimers [(Cowley, et al.,
Journal of Biological Chemistry 272: 19858-19862 (1997)].
[0007] A large number of compounds have been described that either
mimic or block the activity of 17.beta.-estradiol. Compounds having
roughly the same bioogical effects as 17.beta.-estradiol, the most
potent endogenous estrogen, are referred to as "estrogen receptor
agonists". Those which, when given in combination with
17.beta.-estradiol, block its effects are called "estrogen receptor
antagonists". In reality there is a continuum between estrogen
receptor agonist and estrogen receptor antagonist activity and
indeed some compounds behave as estrogen receptor agonists in some
tissues and estrogen receptor antagonists in others. These
compounds with mixed activity are called selective estrogen
receptor modulators (SERMS) and are therapeutically useful agents
(e.g. EVISTA) [McDonnell, Journal of the Society for Gynecologic
Investigation 7: S10-S15 (2000), Goldstein, et al., Human
Reproduction Update 6: 212-224 (2000)]. The precise reason why the
same compound can have cell-specific effects has not been
elucidated, but the differences in receptor conformation and/or in
the milieu of coregulatory proteins have been suggested.
[0008] It has been known for some time that estrogen receptors
adopt different conformations, when binding ligands. However, the
consequence and subtlety of these changes has been only recently
revealed. The three dimensional structures of ER.alpha. and
ERO.beta. have been solved by co-crystallization with various
ligands and clearly show the repositioning of helix 12 in the
presence of an estrogen receptor antagonist which sterically
hinders the protein sequences required for receptor coregulatory
protein interaction [Pike, et al., Embo 18: 4608-4618 (1999),
Shiau, et al., Cell 95: 927-937 (1998)]. In addition, the technique
of phage display has been used to identify peptides that interact
with estrogen receptors in the presence of different ligands
(Paige, et al., Proceedings of the National Academy of Sciences of
the United States of America 96: 3999-4004 (1999)]. For example, a
peptide was identified that distinguished between ER.alpha. bound
to the full estrogen receptor agonists 17.beta.-estradiol and
diethylstilbesterol. A different peptide was shown to distinguish
between clomiphene bound to ER.alpha. and ER.beta.. These data
indicated that each ligand potentially places the receptor in a
unique and unpredictable conformation that is likely to have
distinct biological activities.
[0009] As mentioned above, estrogens affect a panoply of biological
processes. In addition, where gender differences have been
described (e.g. disease frequencies, responses to challenge, etc),
it is possible that the explanation involves the difference in
estrogen levels between males and females.
DESCRIPTION OF THE INVENTION
[0010] This invention provides estrogenic compound of formula I
having the structure, ##STR2## wherein [0011] A is alkyl of 1-6
carbon atoms, halogen, trifluoroalkyl of 1-6 carbon atoms,
hydroxyalkyl of 1-6 carbon atoms, --CO.sub.2H, --NH.sub.2--, or
--OP; [0012] A' is --OP, --CO.sub.2P, halogen, or hydroxyalkyl;
[0013] P is hydrogen, alkyl of 1-6 carbon atoms, or phenyl; [0014]
Z is hydrogen, alkyl of 1-6 carbon atoms, halogen, --N.sub.2, --CN,
triflouroalkyl of 1-6 carbon atoms, --COP, --CO.sub.2P, or
--C(P).dbd.N--OP; [0015] R and R' are each, independently,
hydrogen, alkyl of 1-6 carbon atoms, alkenyl of 2-7 carbon atoms,
halogen, --OP, --SP, --SOP, --SO.sub.2P, --SCN, trifluoroalkyl, of
1-6 carbon atoms, --CF.sub.2CF.sub.3, trifluoroalkoxy of 1-6 carbon
atoms, --NO.sub.2, --NH.sub.2, --NHOP, hydroxyalko of 1-6 carbon
atoms, alkoxyalkyl of 1-6 carbon atoms per alkyl group, -alkyl-SP,
-alkyl-SOP, -alkyl-SO.sub.2P, --CN, -alkyl-CN, -alkenyl-CN,
-alkylSCN, --CHFCN, --CF.sub.2CN, -alkenyl-NO.sub.2, haloalkyl of
1-6 carbon atoms, dihaloalkenyl of 2-7 carbon atoms, --COP,
--COCF.sub.3, --CO.sub.2P, --CONR.sub.1R.sub.2,
-alkyl-CONR.sub.1R.sub.2, -alkenyl-CONR.sub.1R.sub.2, -alkyl-COP,
-alkenyl-COP, -alkenyl-CO.sub.2P, -alkenyl-CO.sub.2P, oxadiazolyl,
furyl, thienyl, pyrolyl, imidazolyl, triazolyl, or tetrazolyl;
[0016] X and Y are each, independently, hydrogen, alkyl of 1-6
carbon atoms, halogen, --NO2, --CN, trifluoroalkyl of 1-6 carbon
atoms, --OP, hydroxyalkyl of 1-6 carbon atoms, --CO.sub.2H, or
phenyl which is optionally mono- or di-substituted with hydroxyl,
benzyloxy, alkoxy of 1-6 carbon atoms, or
--OCH.sub.2CH.sub.2NR.sub.1R.sub.2; [0017] R.sub.1 and R.sub.2 are
each, independently, hydrogen, alkyl of 1-6 carbon atoms, or alkoxy
of 1-6 carbon atoms; or R.sub.1 and R.sub.2 are concatenated
together as --(CH.sub.2).sub.p--, [0018] p=2-6; or a
pharmaceutically acceptable salt thereof.
[0019] Pharmaceutically acceptable salts can be formed from organic
and inorganic acids, for example, acetic, propionic, lactic,
citric, tartaric, succinic, fumaric, maleic, malonic, mandelic,
malic, phthalic, hydrochloric, hydrobromic, phosphoric, nitric,
sulfuric, methanesulfonic, napthalenesulfonic, benzenesulfonic,
toluenesulfonic, camphorsulfonic, and similarly known acceptable
aids when a compound of this invention contains a basic moiety.
Salts may also be formed from organic and inorganic bases, such as
alkali metal salts (for example, sodium, lithium, or potassium)
alkaline earth metal salts, ammonium salts, alkylammonium salts
containing 1-6 carbon atoms or dialkylammonium salts containing 1-6
carbon atoms in each alkyl group, and trialkylammonium salts
containing 1-6 carbon atoms in each alkyl group, when a compound of
this invention contains an acidic moiety.
[0020] The terms alkyl, alkenyl, and alkynyl include both branched
and straight chain moieties. The terms alkyl, alkenyl, and alkynyl
include both unsubstituted and substitituted moieties.
Unsubstituted examples include methyl, ethyl, propyl, butyl,
isopropyl, sec-butyl, tert-butyl, vinyl, allyl, acetylene, 1-methyl
vinyl, and the like. When alkyl or alkenyl moieties are
substituted, they may typically be mono-, di, tri- or
persubstituted. Halogen is the preferred substituent for
substituted alkyl, alkenyl, or alkynyl moieties. Examples for a
halogen substituent include 1-bromo vinyl, 1-fluoro vinyl,
1,2-difluoro vinyl, 2,2-difluorovinyl, 1,2,2-trifluorovinyl,
1,2-dibromo-ethane, 1,2 difluro ethane, 1-fluoro-2-bromo ethane,
CF.sub.2CF.sub.3, CF.sub.2CF.sub.2CF.sub.3, and the like. An
example of a substituted cyanoalkyl group would be --CHFCN. The
term halogen includes bromine, chlorine, fluorine, and iodine.
[0021] As used in accordance with this invention, the term
"providing," with respect to providing a compound or substance
covered by this invention, means either directly administering such
a compound or substance, or administering a prodrug, derivative, or
analog which will form the effective amount of the compound or
substance within the body.
[0022] Of the compounds of this invention, it is preferred that the
compound of formula I has the structure ##STR3## wherein [0023] P
and P' are each, independently, hydrogen, alkyl of 1-6 carbon
atoms, or acyl of 2-7 carbon atoms; [0024] X is hydrogen or
halogen; [0025] R is hydrogen, alkyl of 1-6 carbon atoms, halogen,
--CN, or --CHO, [0026] R' is alkoxy of 1-6 carbon atoms, or
cyanoalkyl having 1-6 carbon atoms in the alkyl moiety; [0027] or a
pharmaceutically acceptable salt thereof.
[0028] It is more preferred that X if fluorine; and still more
preferred that X is fluorine; R is --CN, and R' is --OCH.sub.3. It
is also more preferred that X is hydrogen or F; R is hydrogen or F;
and R' is --CH.sub.2CN.
[0029] The reagents used in the preparation the compounds of this
invention can be either commercially obtained or can be prepared by
standard procedures transcribed in the literature. The compounds of
the present invention can be prepared according to the following
synthetic schemes. ##STR4## ##STR5## ##STR6## ##STR7## ##STR8##
##STR9## ##STR10## ##STR11## ##STR12## ##STR13## ##STR14##
##STR15## ##STR16## ##STR17## ##STR18## ##STR19## ##STR20##
##STR21## ##STR22## ##STR23## ##STR24## ##STR25##
[0030] Standard pharmacological test procedures are readily
available to determine the activity profile of a given test
compound. The following briefly summarizes several representative
test procedures and may include data for representative compounds
of the invention. All assays, except the radioligand binding assay,
can be used to detect estrogen receptor agonist or antagonist
activity of compounds. In general, estrogen receptor agonist
activity is measured by comparing the activity of the compound to a
reference estrogen (e.g. 17.beta.-estradiol,
17.alpha.-ethinyl,17.beta.-estradiol, estrone, diethylstilbesterol
etc). Estrogen receptor antagonist activity is generally measured
by co-treating the test compound with the reference estrogen and
comparing the result to that obtained with the reference estrogen
alone. Standard pharmacological test procedures for SERMs are also
provided in U.S. Pat. Nos. 4,418,068 and 5,998,402 which are hereby
incorporated by reference.
Evaluation of Binding Affinities to ER.alpha. and ER.beta.
[0031] Representative examples of the invention were evaluated for
their ability to compete with 17.beta.-estradiol for both ER.alpha.
and ER.beta. in a conventional radioligand binding assay. This test
procedure provides the methodology for one to determine the
relative binding affinities for the ER.alpha. or ER.beta.
receptors. The procedure used is briefly described below.
[0032] Preparation of receptor extracts for characterization of
binding selectivity. The ligand binding domains, conveniently
defined here as all sequence downstream of the DNA binding domain,
were obtained by PCR using full length cDNA as templates and
primers that contained appropriate restriction sites for subcloning
while maintaining the appropriate reading frame for expression.
These templates contained amino acids M.sub.250-V.sub.595 of human
ER.alpha. [Green, et al., Nature 320: 134-9 (1986)] and
M.sub.214-Q.sub.530 of human ER.beta. [Ogawa, et al., Biochemical
& Biophysical Research Communications 243: 122-6 (1998)]. Human
ER.beta. was cloned into pET15b (Novagen, Madison Wis.) as a
Nco1-BamH1 fragment bearing a C-terminal Flag tag. Human ER.alpha.
was cloned as for human ER.beta. except that an N-terminal His tag
was added. The sequences of all constructs used were verified by
complete sequencing-of both strands.
[0033] BL21(DE3) cells were used to express the human proteins.
Typically a 10 mL overnight culture was used to inoculate a 1 L
culture of LB medium containing 100 .mu.g/mL of ampicillin. After
incubation overnight at 37.degree. C. IPTG was added to a final
concentration of 1 mM and incubation proceeded at 25.degree. C. for
2 hours. Cells were harvested by centrifugation (1500.times.g) and
the pellets washed with and resuspended in 100 mL of 50 mM Tris-Cl
(pH 7.4), 150 mM NaCl. Cells were lysed by passing twice through a
French press at 12000 psi. The lysate was clarified by
centrifugation at 12,000.times.g for 30 minutes at 4.degree. C. and
stored at -70.degree. C.
[0034] Evaluation of extracts for specific [.sup.3H]-estradiol
binding. Dulbecco's phosphate buffered saline (Gibco, 1.times.
final concentration) supplemented with 1 mM EDTA was used as the
assay buffer. To optimize the amount of receptor to use in the
assay, [.sup.3H]-17.beta.-estradiol (New England Nuclear; final
concentration=2 nM).+-.0.6 .mu.M diethylstilbestrol and 100 .mu.L
of various dilutions of the E. coli lysate were added to each well
of a high binding masked microtiter plate (EG&G Wallac). The
final assay volume was 120 .mu.L and the concentration of DMSO was
.ltoreq.1%. After incubation at room temperature for 5-18 hours,
unbound material was aspirated and the plate washed three times
with approximately 300 .mu.L of assay buffer. After washing, 135
.mu.L of scintillation cocktail (Optiphase Supermix, EG&G
Wallac) was added to the wells, and the plate was sealed and
agitated for at least 5 minutes to mix scintillant with residual
wash buffer. Bound radioactivity was evaluated by liquid
scintillation counting (EG&G Wallac Microbeta Plus).
[0035] After determining the dilution of each receptor preparation
that provided maximum specific binding, the assay was further
optimized by estimating the IC.sub.50 of unlabelled
17.beta.-estradiol using various dilutions of the receptor
preparation. A final working dilution for each receptor preparation
was chosen for which the IC.sub.50 of unlabelled 17.beta.-stradiol
was 2-4 nM.
[0036] Ligand binding competition test procedure. Test compounds
were initially solubilized in DMSO and the final concentration of
DMSO in the binding assay was .ltoreq.1%. Eight dilutions of each
test compound were used as an unlabelled competitor for
[.sup.3H]-17.beta.-estradiol. Typically, a set of compound
dilutions would be tested simultaneously on human ER.alpha. and
ER.beta.. The results were plotted as measured DPM vs.
concentration of test compound. For dose-response curve fitting, a
four parameter logistic model on the transformed, weighted data was
fit and the IC.sub.50 was defined as the concentration of compound
decreasing maximum [.sup.3H]-estradiol binding by 50%.
[0037] Binding affinities for ER.alpha.-and ER.beta. (as measured
by IC.sub.50) for representative examples of the invention are
shown in Table (1). TABLE-US-00001 TABLE 1 ER binding affinities of
representative compounds of the invention Example ER-.beta.
IC.sub.50 (nM) ER-.alpha. IC.sub.50 (nM) 3 0.038 0.744 4 0.029 0.98
5 0.014 1.16 6 0.016 0.207 7 0.031 0.588 8 0.050 0.522 9 0.0056
0.114 10 0.052 0.055 11 0.015 0.070 12 0.067 0.156 13 >5 >5
14 0.66 9.7 15 0.011 0.212 16 0.62 3.53 21 0.026 0.217 22 0.052
0.159 25 0.31 5.66 27 0.0022 0.093 30 0.0018 0.043 32 0.038 0.186
35 0.010 0.039 36 0.083 0.93 37 0.043 0.577 38 0.043 1.35 39 0.028
0.504 43 0.010 1.056 43a 0.008 0.625 48 0.0011 0.023 49 0.004 0.109
57 0.0016 0.007 58 0.0016 0.015 59 0.075 0.606 60 0.17 1.21 61 2.69
>5 62 0.009 0.487 63 0.00073 0.0075 64 0.009 0.161 65 0.080
0.849 67 0.0017 0.046 68 0.015 0.38 69 0.0025 0.114 70 0.00034
0.021 71 0.074 2.42 72 0.151 1.78 73 0.032 1.65 73a 0.042 2.959 75
0.006 0.178 77 0.006 0.089 80 0.0076 0.097 89 0.290 4.050 90 0.840
>5 91 0.600 7.300 92 >5 >5 93 0.834 0.185 94 0.893 0.065
95 3.11 0.365 96 0.520 2.330 99 0.0011 0.0017 100 0.26 1.78 102
0.002 0.031 103 0.0069 0.0041 104 0.033 0.045 105 0.0081 0.0029 108
1.69 0.646 110 0.019 0.327 111 0.031 0.352 113 0.108 0.834 118
0.0052 0.039 119 0.85 >5 120 0.007 0.263 121 0.006 0.103 122
0.0032 0.049 126 0.009 0.212 128 7.000 >5 129 >5 >5 130
0.0021 0.044 131 0.0026 0.041 132 0.034 0.422 135 0.008 0.264 136
0.014 0.452 138 0.648 >5 141 0.0021 0.066 143 1.600 >5 144
>5 >5
[0038] The results obtained in the standard pharmacologic test
procedure described above demonstrate that the compounds of this
invention bind both subtypes of the estrogen receptor. The
IC.sub.50s are generally lower for ER.beta., indicating these
compounds are preferentially ER.beta. selective ligands, but some
are still considered active at ER.alpha.. Compounds of this
invention will exhibit a range of activity based, at least
partially, on their receptor affinity selectivity profiles. Since
the compounds of the invention bind ER-.beta. with higher affinity
than ER.alpha., they will be useful in treating or inhibiting
diseases than can be modulated via ER.beta.. Additionally, since
each receptor ligand complex is unique and thus its interaction
with various coregulatory proteins is unique, compounds of this
invention will display different and unpredictable activities
depending on cellular context. For example, in some cell-types, it
is possible for a compound to behave as an estrogen receptor
agonist while in other tissues, an estrogen receptor antagonist.
Compounds with such activity have sometimes been referred to as
SERMs (Selective Estrogen Receptor Modulators). Unlike many
estrogens, however, many of the SERMs do not cause increases in
uterine wet weight. These compounds are antiestrogenic in the
uterus and can completely antagonize the trophic effects of
estrogen receptor agonists in uterine tissue. These compounds,
however, act as estrogen receptor agonists in the bone,
cardiovascular, and central nervous systems. Due to this tissue
selective nature of these compounds, they are useful in treating or
inhibiting in a mammal disease states of syndromes which are caused
or associated with an estrogen deficiency (in certain tissues such
as bone or cardiovascular) or an excess of estrogen (in the uterous
or mammary glands). In addition, compounds of this invention also
have the potential to behave as estrogen receptor agonists on one
receptor type while behaving as estrogen receptor antagonists on
the other. For example, it has been demonstrated that. compounds
can be antagonize the action of 17.beta.-estradiol via ER.beta.
wile exhibiting estrogen receptor agonist activity with ER.alpha.
(Sun, et al., Endocrinology 140: 800-804 (1999)]. Such ERSAA
(Estrogen Receptor Selective Agonist Antagonist) activity provides
for pharmacologically distinct estrogenic activity within this
series of compounds
Regulation of Metallothionein II mRNA
[0039] Estrogens acting through ER.beta., but not ER.alpha. can
upregulate metallothionein II mRNA levels in Saos-2 cells as
described by Harris (Endocrinology 142: 645-652 (2001)]. Results
from this test procedure can be combined with results from the test
procedure described below (ERE reporter test procedure) to generate
a selectivity profile for compounds of this invention (see also WO
00/37681). Data for representative compounds of the invention are
shown in Table (2). TABLE-US-00002 TABLE 2 Regulation of
metallothionein-II mRNA in Saos-2 cells Compound Fold Induction at
1 uM 75 12 103 9
Evaluation of Test Compound Using an ERE-Reporter Test Procedure in
MCF-7 Breast Cancer Cells
[0040] Stock solutions of test compounds (usually 0.1 M) are
prepared in DMSO and then diluted 10 to 100-fold with DMSO to make
working solutions of 1 or 10 mM. The DMSO stocks are stored at
either 4.degree. C. (0.1 M) or -20.degree. C. (<0.1M). MCF-7
cells are passaged twice a week with growth medium [D-MEM/F-12
medium containing 10% (v/v) heat-inactivated fetal bovine serum, 1%
(v/v) Penicillin-Streptomycin, and 2 mM glutaMax-1]. The cells are
maintained in vented flasks at 37.degree. C. inside a 5%
CO.sub.2/95% humidified air incubator. One day prior to treatment,
the cells are plated with growth medium at 25,000 cells/well into
96 well plate and incubated at 37.degree. C. overnight.
[0041] The cells are infected for 2 ht at 37.degree. C. with 50
.mu.l/well of a 1:10 dilution of adenovirus 5-ERE-tk-luciferase in
experimental medium [phenol red-free D-MEM/F-12 medium containing.
10% (v/v) heat-inactivated charcoal-stripped fetal bovine serum, 1%
(v/v) Penicillin-Streptomycin, 2 mM glutaMax-1, 1 mM sodium
pyruvate]. The wells are then washed once with 150 .mu.l of
experimental medium. Finally, the cells are treated for 24 hr at
37.degree. C. in replicates of 8 wells/treatment with 150
.mu.l/well of vehicle (.ltoreq.0.1% v/v DMSO) or compound that is
diluted .gtoreq.1000-old into experimental medium.
[0042] Initial screening of test compounds is done at a single dose
of 1 .mu.M that is tested alone (estrogen receptor agonist mode) or
in combination with 0.1 nM. 17.beta.-stradiol (EC.sub.80; estrogen
receptor antagonist mode). Each 96 well plate also includes a
vehicle control group (0.1% v/v DMSO) and an estrogen receptor
agonist control group (either 0.1 or 1 nM 17.beta.-estradiol).
Dose-response experiments are performed in either the estrogen
receptor agonist and/or estrogen receptor antagonist modes on
active. compounds in log increases from 10.sup.-14 to 10.sup.-5 M.
From these dose-response curves, EC.sub.50 and IC.sub.50 values:
respectively, are generated. The final well in each treatment group
contains 5 .mu.l of 3.times.10.sup.-5 M ICI-182,780 (10.sup.-6 M
final concentration) as an estrogen receptor antagonist
control.
[0043] After treatment, the cells are lysed on a shaker for 15 min
with 25 .mu.l/well of 1.times. cell culture lysis reagent (Promega
Corporation). The cell lysates (20 .mu.l) are transferred to a 96
well luminometer plate, and luciferase activity is measured in a
MicroLumat LB 96 P luminometer (EG & G Berthold) using 100
.mu.l/well of luciferase substrate (Promega Corporation). Prior to
the injection of substrate, a 1 second background measurement is
made for each well. Following the injection of substrate,
luciferase activity is measured for 10 seconds after a 1 second
delay. The data are transferred from the luminometer to a Macintosh
personal computer and analyzed using the JMP software (SAS
Institute); this program subtracts the background reading from the
luciferase measurement for each well and then determines the mean
and standard deviation of each treatment.
[0044] The luciferase data are transformed by logarithms, and the
Huber M-estimator is used to down-weight the outlying transformed
observations. The JMP software is used to analyze the transformed
and weighted data for one-way ANOVA (Dunnett's test). The compound
treatments are compared to the vehicle control results in the
estrogen receptor agonist more, ore the positive estrogen receptor
agonist control results (0.1 nM 17.beta.-estradiol) in the estrogen
receptor antagonist mode. For the initial single dose experiment,
if the compound treatment results are significantly different from
the appropriate control (p<0.05), then the results are reported
as the percent relative to the 17.beta.-estradiol control [i.e.,
((compound vehicle control)/(17.beta.-estradiol control--vehicle
control)).times.100]. The JMP software is also used to determine
the EC.sub.50 and/or IC.sub.50 values from the non-linear
dose-response curves.
Evaluation of Uterotrophic Activity
[0045] Uterotrophic activity of a test compound can be measured
according to the following standard pharmacological test
procedures.
[0046] Procedure 1: Sexually immature (18 days of age)
Sprague-Dawley rats are obtained from Taconic and provided
unrestricted access to a casein-based diet (Purina Mills 5K96C) and
water. On day 19, 20 and 21 the rats are dosed subcutaneously with
17.alpha.-ethinyl-17.beta.-estradiol (0.06 .mu.g/rat/day), test
compound or vehicle (50% DMSO/50% Dulbecco's PBS). To assess
estrogen receptor antagonist, compounds are coadministered with
17.alpha.-ethinyl-17.beta.-estradiol (0.06 .mu.g/rat/day). There
are six rats/group and they are euthanized approximately 24 hours
after the last injection by CO.sub.2 asphyxiation and pneumothorax.
Uteri are removed and weighed after trimming associated fat and
expressing any internal fluid. A tissue sample can also be snap
frozen for analysis of gene expression (e.g. complement factor 3
mRNA).
Evaluation of Osteoporosis and Lipid Modulation
(Cardioprotection)
[0047] Female Sprague-Dawley rats, ovariectomized or sham operated,
are obtained 1 day after surgery from Taconic Farms (weight range
240-275 g). They are housed 3 or, 4 rats/cage in a room on a 12/12
(right/dark) schedule and provided with food (Purina 5K96C rat
chow) and water ad libitum. Treatment for all studies begin 1 day
after arrival and rats are dosed 7 days per week as indicated for 6
weeks. A group of age matched sham operated rats not receiving any
treatment serve as an intact, estrogen replete control group for
each study.
[0048] All test compounds are prepared in a vehicle of 50% DMSO (J
T Baker, Phillipsburg, N.J.)/1.times. Dulbecco's phosphate saline
(GibcoBRL, Grand Island, N.Y.) at defined concentrations so that
the treatment volume is 0.1 mL/100 g body weight.
17.beta.-estradiol is dissolved in corn oil (20 .mu.g/mL) and
delivered subcutaneously, 0.1 mL/rat. All dosages are adjusted at
three week intervals according to group mean body weight
measurements, and given subcutaneously.
[0049] Five weeks after the initiations of treatment and one week
prior to the termination of the study, each rat is evaluated for
bone mineral den (BMD). The total and trabecular density of the
proximal tibia are evaluated in anesthetized rats using an XCT-960M
(pQCT; Stratec Medizintechnik, Pforzheim, Germany). The
measurements are performed as follows: Fifteen minutes prior to
scanning, each rat is anesthetized with an intraperitoneal
injection of 45 mg/kg ketamine, 8.5 mg/kg xylazine, and 1.5 mg/kg
acepromazine.
[0050] The right hind limb is passed through a polycarbonate tube
with a diameter of 25 mm and taped to an acrylic frame with the
ankle joint at a 90.degree. angle and the knee joint at
180.degree.. The polycarbonate tube is affixed to a sliding
platform that maintains it perpendicular to the aperture of the
pQCT. The platform is adjusted so that the distal end of the femur
and the proximal end of the tibia is in the scanning field. A two
dimensional scout view is run for a length of 10 mm and a line
resolution of 0.2 mm. After the scout view is displayed on the
monitor, the proximal end of the tibia is located. The pQCT scan is
initiated 3.4 mm distal from this point. The pQCT scan is 1 mm
thick, has a voxel (three dimensional pixel) size of 0.140 mm, and
consists of 145 projections through the slice.
[0051] After the pQCT scan is completed, the image is displayed on
the monitor. A region of interest including the tibia but excluding
the fibula is outlined. The soft tissue is mathematically removed
using an iterative algorithm. The density of the remaining bone
(total density) is reported in mg/cm.sup.3. The outer 55% of the
bone is mathematically peeled away in a concentric spiral. The
density of the remaining bone (Trabecular density) is reported in
mg/cm.sup.3.
[0052] One week after BMD evaluation the rats are euthanized by
CO.sub.2 asphyxiation and pneumothorax, and blood is collected for
cholesterol determination. The uteri- are also removed and the
weighed after trimming associated fat and expressing any luminal
fluid. Total cholesterol is determined using a Boehringer-Mannheim
Hitachi 911 clinical analyzer using the Cholesterol/HP kit.
Statistics are compared using one-way analysis of variance with
Dunnet's test.
Evaluation of Antioxidant Activity
[0053] Porcine aortas are obtained from an abattoir, washed,
transported in chilled PBS, and aortic erdothelial cells are
harvested. To harvest the cells, the intercostal vessels of the
aorta are tied off and one end of the aorta clamped. Fresh, sterile
filtered, 0.2% collagenase (Sigma Type I) is placed in the vessel
and the other end of the vessel then damped to form a dosed system.
The aorta is incubated at 37.degree. C. for 15-20 minutes, after
which the collagenase solution is collected and centrifuged for 5
minutes at 2000.times.g. Each pellet is suspended in 7 mL of
endothelial cell culture medium consisting of phenol red free
DMEM/Ham's F12 media supplemented with charcoal stripped FBS (5%),
NuSerum (5%), L-glutamine (4 mM), penicillin-streptomycin (1000
U/ml, 100 .mu.g/ml) and gentamycin (75 .mu.g/ml), seeded in 100 mm
petri dish and incubated at 37.degree. C. in 5% CO.sub.2. After 20
minutes, the cells are rinsed with PBS and fresh medium added, this
was repeated again at 24 hours. The cells are confluent after
approximately 1 week. The endothelial cells are routinely fed twice
a week and, when confluent, trypsinized and seeded at a 1:7 ratio.
Cell mediated oxidation of 12.5 .mu.g/mL LDL is allowed to proceed
in the presence of the compound to be evaluated (5 .mu.M) for 4
hours at 37.degree. C. Results are expressed as the percent
inhibition of the oxidative process as measured by the TBARS
(thiobarbituric acid reactive substances) method for analysis of
free aldehydes [Yagi, Biochemical Medicine 15: 212-6 (1976)].
Rat Hot Flush Test Procedure
[0054] The effect of test compounds on hot flushes can be evaluated
in a standard pharmacological test procedure which measures the
ability of a test compound to blunt the increase in tail skin
temperature which occurs as morphine-addicted rats are acutely
withdrawn from the drug using naloxone (Merchenthaler, et al.,
Maturitas 30: 307-16 (1998)]. It can also be used to detect
estrogen receptor antagonist activity by co-dosing test compound
with the reference estrogen.
Evaluation of Vasomotor Function in Isolated Rat Aortic Rings
[0055] Sprague-Dawley rats (240-260 grams) are divided into 4
groups: [0056] 1. Normal non-overiectomized (Intact) [0057] 2.
Ovariectomized (ovex) vehicle treated [0058] 3. Ovariectomized
17.beta.-estradiol treated (1 mg/kg/day) [0059] 4. Ovariectomized
animals treated with test compound (various doses)
[0060] Animals ovariectomized approximately 3 weeks prior to
treatment. Each animal receives either 17-.beta. estradiol sulfate
(1 mg/kg/day) or test compound suspended In distilled, deionized
water with 1% tween-80 by gastric gavage. Vehide treated animals
received an appropriate volume of the vehicle used in the drug
treated groups.
[0061] Animals are euthanized by CO.sub.2 inhalation and
exsanguination. Thoracic aortae are rapidly removed and placed in
37.degree. C. physiological solution with the following composition
(mM): NaCl (54.7), KCl (5.0), NaHCO.sub.3 (25.0), MgCl.sub.2
2H.sub.2O (2.5), D-glucose (11.8) and CaCl.sub.2 (0.2) gassed with
CO.sub.2--O.sub.2, 95%/5% for a final pH of 7.4. The advantitia is
removed from the outer surface and the vessel is cut into 2-3 mm
wide rings. Rings are suspended in a 10 mL tissue bath with one end
attached to the bottom of the bath and the other to a force
transducer. A resting tension of 1 gram is placed on the rings.
Rings are equilibrated for 1 hour, signals are acquired and
analyzed.
[0062] After equilibration, the rings are exposed to increasing
concentrations of phenylephrine (10.sup.-8 to 10.sup.-4 M) and the
tension recorded. Baths are then rinsed 3 times with fresh buffer.
After washout, 200 mM L-NAME is added to the tissue bath and
equilibrated for 30 minutes. The phenylephrine concentration
response curve is then repeated.
Evaluation of Cardioprotective Activity
[0063] Apolipoprotein E-deficient C57/B1J (apo E KO) mice are
obtained from Taconic Farms. All animal procedures are performed
under strict compliance to IACUC guidelines. Ovariectomized female
apo E KO mice; 4-7 weeks of age, are housed in shoe-box cages and
were allowed free access to food and water. The animals are
randomized by weight into groups (n=12-15 mice per group). The
animals are dosed with test compounds or estrogen
(17.beta.-estradiol sulfate at 1 mg/kg/day) in the diet using a
Precise-dosing Protocol, where the amount of diet consumed is
measured weekly, and the dose adjusted accordingly, based on animal
weight. The diet used is a Western-style diet (57U5) that is
prepared by Purina and contains 0.50% cholesterol, 20% lard and 25
IU/KG Vitamin E. The animals are dosed/fed using the paradigm for a
period of 12 weeks. Control animals are fed the Western-style diet
and receive no compound. At the end of the study period, the
animals are euthanized and plasma samples obtained. The hearts are
perfused in situ, first with saline and then with neutral buffered
10% formalin solution.
[0064] For the determination of plasma lipids and lipoproteins,
total cholesterol and triglycerides are determined using enzymatic
methods with commercially available kits from Boehringer Mannheim
and Wako Biochemicals, respectively and analyzed using the
Boehringer Mannheim Hitachi 911 Analyzer. Separation and
quantification of plasma lipoproteins were performed using FPLC
size fractionation. Briefly, 50-100 mL of serum is filtered and
injected into Superose 12 and Superose 6 columns connected in
series and eluted at a constant flow rate with 1 mM sodium EDTA and
0.15 M NaCl. Areas of each curve representing VLDT, LDL and HOL are
integrated using Waters Millennium.TM. software, and each
lipoprotein fraction is quantified by multiplying the Total
Cholesterol value by the relative percent area of each respective
chromatogram peak.
[0065] For the quantification of aortic atherosclerosis, the aortas
are carefully isolated and placed in formalin fixative for 48-72
hours before handling. Atherosclerotic lesions are identified using
Oil Red O staining. The vessels are briefly destained, and then
imaged using a Nikon SMU800 microscope fitted with a Sony 3CCQ
video camera system in concert with IMAQ Configuration Utility
(National Instrument) as the image capturing software. The lesions
are quantified en face along the aortic arch using a custom
threshold utility software package (Coleman Technologies).
Automated lesion assessment is performed on the vessels using the
threshold function of the program, specifically-on the region
contained within the aortic arch from the proximal edge of the
brachio-cephalic trunk to the distal edge of the left subelavian
artery. Aortic atherosclerosis data are expressed as percent lesion
involvement strictly within this defined luminal area.
Evaluation of Cognition Enhancement
[0066] Ovariectomized rats (n=50) are habituated to an 8-arm radial
arm maze for 10-min periods on each of 5 consecutive days. Animals
are water-deprived prior to habituation and testing. A 100 .mu.L
aliquot of water placed at the ends of each arm serves as
reinforcement Acquisition of a win-shift task in the radial arm
maze is accomplished by allowing the animal to have access to one
baited arm. After drinking, the animal exits the arm and re-enters
the central compartment, where it now has access to the previously
visited arm or to a novel arm. A correct response is recorded when
the animal chooses to enter a novel arm. Each animal is given 5
trials per day for 3 days. After the last acquisition trial, the
animals are assigned to one of the following 4 groups:
[0067] 1. Negative controls: injected with 10% DMSO/sesame oil
vehicle once daily for 6 days (1 mL/kg, SC)
[0068] 2. Positive controls: Injected with 17.beta.-ostradiol
benzoate for 2 days and tested 4 days after the second injection
(17.beta.-esteradiol benzoate at 10 .mu.g/0.1 mL per rat)
[0069] 3. Estradiol: 17.beta.-estradiol will be injected daily for
6 days (20 .mu.g/kg, SC)
[0070] 4. Test compound: injected daily for 6 days (doses
vary).
All injections will begin after testing on the last day of
acquisition. The last injection for groups 1, 3, and 4 will take
place 2 hours before testing for working memory.
[0071] The test for working memory is a delayed
non-matching-to-sample task (DNMS) utilizing delays of 15, 30, or
60 seconds. This task is a variation of the acquisition task in
which the rat is placed in the central arena and allowed to enter
one arm as before. A second arm is opened once the rat traverses
halfway down the first arm, and again the rat is required to choose
this arm. When it has traveled halfway down this second arm, both
doors are closed and the delay is instituted. Once the delay has
expired, both of the original two doors, and a third novel door,
are opened simultaneously. A correct response is recorded when the
animal travels halfway down the third, novel arm. An incorrect
response is recorded when the animal travels halfway down either
the first or second arms. Each animal will receive 5 trials at each
of the three delay intervals for a total of 15 trials per
subject.
Evaluation of Effect on Pleurisy
[0072] The ability to reduce the symptoms of experimentally-induced
pleurisy in rats can be evaluated according to the procedure of
Cuzzocrea [Endocrinology 141: 1455-63 (2000)].
Evaluation of Protection Against Glutamate-Induced Cytotoxicity
(Neuroprotection)
[0073] The neuroprotective activity of compounds of this invention
can be evaluated in an in vitro standard pharmacological test
procedure using glutarnate challenge [Zaulyanov, et al, Cellular
& Molecular Neurobiology 19: 705-18 (1999); Prokal, et al.;
Journal of Medicinal Chemistry 44: 110-4 (2001)].
Evaluation in the Mammary End Bud Test Procedure
[0074] Estrogens are required for full ductal elongation and
branching of the mammary ducts, and the subsequent development of
lobulo-alveolar end buds under the influence of progesterone. In
this test procedure, the mammotrophic activity of selected
compounds of the invention was evaluated according to the following
standard pharmacological test procedure. Twenty-eight day old
Sprague-Dawley rats (Taconic Farms, Germantown, N.Y.) were
ovariectomized and rested for nine days. Animals were housed under
a 12-hour light/dark cycle and fed a casein-based Purina Laboratory
Rodent Diet 5K96 (Purina, Richmond, Ind.) and allowed free access
to water. Rats were then dosed subcutaneously for six days with
vehicle (50% DMSO (J T Baker, Phillipsburg, N.J.)/50% 1.times.
Dulbecco's Phosphate buffered saline-(GibcoBRL, Grand Island,
N.Y.), 17.beta.-estradiol (0.1 mg/kg) or test compound (20 mg/kg).
For the final three days, rats were also dosed subcutaneously with
progesterone (30 mg/kg). On the seventh day, rats were euthanised
and a mammary fat pad excised. This fat pad was analyzed for casein
kinase II mRNA as a marker of end bud proliferation. Casein kinase
II mRNA was anlayzed by real-time RT-PCR. Briefly, RNA was isolated
following Trizol (GibcoBRL, Grand Island, N.Y.) according to the
manufacture's directions, Samples were treated with DNAse I using
DNA-free kit (Ambion), and casein kinase II mRNA levels were
measured by real-time RT-PCR using the Taqman Gold procedure (PE
Applied Biosystems). A total of 50 ng of RNA was analyzed in
triplicate using casein kinase II specific primer pair (5' primer,
CACACGGATGGCGCATACT; 3' primer, CTCGGGATGCACCATGAAG) and customized
probe (TAMRA-CGGCACTGGTTTCCCTCACATGCT-FAM). Casein kinase II mRNA
levels were normalized to 18 s ribosomal RNA contained within each
sample reaction using primers and probe supplied by PE Applied
Biosystems.
Evaluation in the HLA Rat Standard Pharmacological Test Procedure
for Inflammatory Bowel Disease
[0075] Representative compounds of the invention can be evaluated
in the HLA rat standard pharmacological test procedure which
emulates inflammatory bowel disease in humans. The following
briefly describes the procedure used and results obtained. Male
HLA-B27 rats were obtained from Taconic and provided unrestricted
access to food (PMI Lab diet 5001) and water. Stool quality was
observed daily and graded according to the following scale:
Diarrhea=3; soft stool=2; normal stool=1. At the end of the study,
serum was collected and stored at -70.degree. C. A section of colon
was prepared for histological analysis and an additional segment
was analyzed for myeloperoxidase activity.
[0076] Histological analysis. Colonic tissue was immersed in 10%
neutral buffered formalin. Each specimen of colon was separated
into four samples for evaluation. The formalin-fixed tissues were
processed in a Tissue Tek vacuum infiltration processor (Miles,
Inc; West Haven, Conn.) for paraffin embedding. The samples were
sectioned at 5 .mu.m and then stained with hematoxylin and eosin
(H&E) for blinded histologic evaluations using a scale modified
after Boughton-Smith. After the scores were completed the samples
were unblinded, and data were tabulated and analyzed by ANOVA
linear modeling with multiple mean comparisons. Sections of colonic
tissue were evaluated for several disease indicators and given
relative scores.
Evaluation in Two Models of Arthritis
[0077] Lewis rat assay of adjuvant-induced arthritis. Sixty,
female, 12 weeks old, Lewis rats are housed according to standard
facility operating procedures. They receive a standard regimen of
food and water ad libitum. Each animal is identified by a cage card
indicating the project group and animal number. Each rat number is
marked by indelible ink marker on the tail. At least 10-21 days
before study they are anesthetized and ovariectomized by standard
aseptic surgical techniques.
[0078] Freund's Adjuvant-omplete (Sigma Immuno Chemicals, St.
Louis, Mo.) is used to induce arthritis, each mL containing 1 mg
Mycobacterium tuberculosis heat killed and dried 0.85 mL mineral
oil and 0.15 mL mannide monooleate Lot No. 084H8800.
[0079] The following are examples of two test procedures.
Inhibition test procedure: Thirty rats are injected intradermally
with 0.1 mL of Freund's Adjuvant-complete at the base of the tail.
The animals are randomized to four groups, each group containing
six rats. Each day, the groups receive vehicle (50% DMSO (J T
Baker, Phillipsburg, N.J.)/1.times. Dulbecco's phosphate saline
(GibcoBRL, Grand Island, N.Y.)) or test compound (administered
subcutaneously). All rats began treatment on Day 1. Treatment test
procedure: Thirty rats are injected intradermally with 0.1 mL of
Freund's Adjuvant-Complete at the base of the tail. The animals are
randomized to four groups, each group containing six rats. Each
day, the groups receive vehicle (50% DMSO (J T Baker, Phillipsburg,
N.J.)/1.times. Dulbecco's phosphate saline (GibcoBRL, Grand Island,
N.Y.) or test compound (administered subcutaneously). All rats
began treatment on Day 8 after adjuvant injection. Statistical
analysis is performed using Abacus Concepts Super ANOVA. (Abacus
Concepts, Inc. Berkeley. Calif.). All of the parameters of interest
are subjected to Analysis of Variance with Duncan's new multiple
range post hoc testing between groups. Data are expessed throughout
as mean.+-.standard deviation (SD); and differences were deemed
significant if p<0.05.
[0080] The degree of arthritis severity is monitored daily in terms
of the following disease indices: Hindpaw erythema, hindpaw
swelling, tenderness of the joints, and movements and posture. An
integer scale of 0 to 3 is used to quantify the level of erythema
(0=normal paw, 1=mild erythema, 2=moderate erythema. 3=severe
erythema) and swelling (0=normal paw, 1=mild swelling, 2=moderate
swelling, 3=severe swelling of the hind paw). The maximal score per
day is 12.
[0081] At the end of the study the rats are euthanized with
CO.sub.2, hindlimbs removed at necropsy and fixed in 10% buffered
formalin, and the tarsal joints decalcified and embedded in
paraffin. Histologic sections are stained with Hematoxylin and
Eosin or Saffranin O--Fast Green stain.
[0082] Slides are coded so that the examiner is blinded to the
treatment groups. Synovial tissue from tarsal joints is evaluated
based on synovial hyperplasia, inflammatory cell infiltration, and
pannus formation [Poole and Coombs, International Archives of
Allergy & Applied Immunology 54: 97-113 (1977)] as outlined
below. TABLE-US-00003 Category Grade 1. Synovial lining cells a. No
change 0 b. Cells enlarged, slightly thickened 1 c. Cells enlarged,
increase in numbers, moderately 2 thickened. No villus present d.
Cells enlarged, thickened. Villius present 3 2. Fibroplasia a. No
change 0 b. Fibroplasia present under lining cells 1 c. Small areas
of areolar tissue replaced by fibrous tissue 2 d. Replacement of
areolar tissue by fibrous tissue 3 3. Inflammatory cells a.
Occasionally seen, scattered throughout selection 0 b. Cells
present in small numbers in or just under 1 lining cell layer
and/or around blood vessels. c. Small local collection of cells may
be present 2 d. Large numbers of cells present in capsule and in or
3 under lining cell layers. Large foci often seen. 4. Pannus a. Not
Detectable 0 b. Detectable 1
[0083] In addition, articular cartilage and bone is evaluated using
Mankin's histological grading system [Mankin, et al., Journal of
Bone & Joint Surgery--American Volume 53: 523-37 (1971)] as
shown below. TABLE-US-00004 Category Grade 1. Structure a. Normal 0
b. Surface irregularity 1 c. Pannus and surface irregularity 2 d.
Clefts to transitional zone 3 e. Clefts to radial zone 4 f. Clefts
to calcified zone 5 g. Complete disorganization 6 2. Cells a.
Normal 0 b. Diffuse hypercellularity 1 c. Cloning 2 d.
Hypocellularity 3 3. Safranin-O staining a. Normal 0 b. Slight
reduction 1 c. Modest reduction 2 d. Severe reduction 3 e. No dye
noted 4 4. Tidemark integrity a. Intact 0 b. Crossed by blood
vessels 1
[0084] Evaluation in the HLA-B27 Rat model of arthritis.
Representative compounds of the invention can also be evaluated, in
the HLA-B27 rat standard pharmacological test procedure which
emulates arthritis in humans. The following briefly describes the
procedure used and results obtained: Male HLA-B27 rats can be
obtained from Taconic and provided unrestricted access to a food
(PMI Lab diet 5001) and water. Joint scores and histology are
evaluated as described above for the Lewis rat model of
adjuvant-induced arthritis.
Evaluation in in vivo models of Carcinogeneisis
[0085] The ability of compounds of this invention to treat and
inhibit various malignancies or hyperprolific disorders can be
evaluated in standard pharmacological test procedures that are
readily available in the literature, and include the following two
procedures.
[0086] Breast cancer. Athymic nu/nu (nude) mice are obtained
ovariectomized from Charles River Laboratories (Wilmington Mass.).
One day prior to tumor cell injection, animals are implanted with
time-release pellets containing 0.36-1.7 mg 17.beta.-estradiol (60
or 90 day release, Innovative Research of America, Sarasota, Fla.)
or a placebo. The pellet is introduced subcutaneously into the
intrascapular region using a 10-gauge precision trochar.
Subsequently, mice are injected subcutaneously into the breast
tissue with either 1.times.10.sup.7 MCF-7 cells or 1.times.10.sup.7
BG-1 cells. The cells are mixed with an equal volume of matrigel, a
basement membrane matrix preparation to enhance tumor
establishment; Test compounds can be evaluated either by dosing one
day after tumor cell implantation (inhibition regimen) or after
tumors have reached a certain size (treatment regimen). Compounds
are administered either intraperitoneally or orally in a vehicle of
1% tween-80 in saline each day. Tumor size is evaluated every three
or seven days.
[0087] Colon cancer. The ability to treat or inhibit colon cancer
can be evaluated in the test procedure of Smirnoff [Oncology
Research 11: 25564 (1999)].
Evaluation of Neuroprotection in Two in vivo Test Procedures
[0088] Transient global ischemia in the Mongolian gerbil. The
effect of test compounds on preventing or treating brain injury in
response to oxygen deprivation/reperfusion can be measured using
the following test procedure.
[0089] Female Mongolian gerbils (60-80 g; Charles River
Laboratories, Kingston, N.Y.) were housed in the Wyeth-Ayerst
animal care facility (MALAC certified) with a 12-hour light,
12-hour dark photoperiod and free access to tap water and a
low-estrogen casein diet (Purina; Richmond, Ind.). After
acclimation (3-5 days), gerbils were anesthetized with isoflurane
(2-3% mixture with O.sub.2), ovariectomized (Day 0). Beginning the
following morning (Day 1), gerbils were treated subcutaneously each
day with either vehicle (10% ETOH/corn oil), 17.beta.-estradiol (1
mg/kg, sc) or an experimental compound. On Day 6, gerbils
(n=4-5/group) were anesthetized with isoflurane, the common carotid
arteries visualized via a mid-line neck incision and both arteries
simultaneously occluded for 5 minutes with non-traumatic micro
aneurysm clips. After occlusion, the clips were removed to allow
cerebral reperfusion and the neck incision closed with wound clips.
All animals were fasted overnight prior to the global ischemia
surgey, a step that facilitates consistent ischemic injury. On Day
12, gerbils were exposed to a lethal does of CO.sub.2, and the
brains frozen on dry ice and stored at -80.degree. C. The animal
protocols used for these studies were reviewed and approved by the
Radnor/Collegeville Animal Care and Use Committee (RACCUC/CACUC) at
Wyeth-Ayerst Research.
[0090] The degree of neuronal protection was evaluated by in situ
hybridization analysis of neurogranin mRNA. Briefly, 20 .mu.m
coronal cryostat sections were collected on gelatin-coated slides,
dried and stored at -80.degree. C. At the time of processing, the
desiccated slide boxes were warmed to room temperature, the slides
postfixed in 4% paraformaldehyde, treated with acetic anhydride and
then delipidated and dehydrated with chloroform and ethanol.
Processed section-mounted slides were then hybridized with 200
.mu.l (6.times.10.sup.6 DPM/slide) of an antisense or sense
(control) riboprobe for Neurogranin (.sup.35S-UTP-labeled NG-241;
bases 99-340) in a 50% formamide hybridization mix and incubated
overnight at 55.degree. C. in a humidified slide chamber without
coverslipping. The following morning, the slides were collected in
racks, immersed in 2.times.SSC (0.3 M NaCl, 0.03 M sodium citrate;
pH 7.0)/10 mM DTT, treated with RNase A (20 .mu.g/ml) and washed
(2.times.30 min) at 67.degree. C. in 0.1.times.SSC to remove
nonspecific label. After dehydration, the slides were opposed to
BioMax (BMR-1; Kodak) X-ray film overnight.
[0091] The level of neurogranin hybridization signal was used to
quantitatively assess the degree of neuronal loss in the CA1 region
after injury and to evaluate the efficacy of 17.beta.-estradiol and
experimental compounds. Neurogranin mRNA was selected for these
studies because it is highly expressed in the hippocampal neurons
including CA1, but absent in glia and other cell types present in
this brain region. Therefore, measurement of the amount of
neurogranin mRNA present represents surviving neurons. Relative
optical density measurements of neurogranin hybridization signal
were obtained from film autoradiograms with a computer based image
analysis system (C-Imaging Inc., Pittsburgh, Pa.). The results from
6 sections (40 .mu.m apart) per animal were averaged and
statistically evaluated. Numerical values are reported as the
mean.+-.SEM. One-way analysis of variance was used to test for
differences in the level of neurogranin mRNA and all statements of
non-difference in the results section imply that P>0.05.
[0092] Middle cerebial artery occlusion in mice. Neuroprotection
can be evaluated according to the test procedures described by
Dubal [see, Dubal, et al., Proceedings of the National Academy of
Sciences of the United States of America 98; 1952-1957 (2001),
Dubal, et al., Journal of Neuroscience 19: 6385-6393 (1999)].
Ovulation Inhibition Standard Pharmacological Test Procedure
[0093] The test procedure is used to determine whether test
compounds can inhibit or change the timing of ovulation. It can
also be used to determine the number of oocytes ovulated [Lundeen,
et al., J Steroid Biochem Mol Biol 78: 137-143 (2001)].
[0094] Based on the results obtained in the standard
pharmacological test procedures, the compounds of this invention
are estrogen receptor modulators useful in the treatment or
inhibition of conditions, disorders, or disease states that are at
least partially mediated by an estrogen deficiency or excess, or
which may be treated or inhibited through the use of an estrogenic
agent. The compounds of this invention are particularly useful in
treating a peri-menopausal, menopausal, or postmenopausal patient
in which the levels of endogenous estrogens produced are greatly
diminished. Menopause is generally defined as the last natural
menstrual period and is characterized by the cessation of ovarian
function, leading to the substantial diminution of circulating
estrogen in the bloodstream. As used herein, menopause also
includes conditions of decreased estrogen production that may be
surgically, chemically, or be caused by a disease state which leads
to premature diminution or cessation of ovarian function.
[0095] The compounds of this invention are also useful in
inhibiting or treating other effects of estrogen deprivation
including, hot flushes, vaginal or vulvar atrophy, atrophic
vaginitis, vaginal dryness, pruritus, dyspareunia, dysuria,
frequent urination, urinary incontinence, urinary tract infections.
Other reproductive tract uses include the treatment or inhibition
of dysfunctional uterine bleeding. The compounds are also useful in
treating or inhibiting endometriosis.
[0096] The compounds of this invention are also active in the brain
and are therefore useful for inhibiting or treating Alzheimer's
disease, cognitive decline, decreased libido, senile dementia,
neurodegenerative disorders, depression, anxiety, insomnia,
schizophrenia, and infertility. The compounds of this invention are
also useful in treating or inhibiting benign or malignant abnormal
tissue growth including, glomeruloscierosis, prostatic hypertrophy,
uterine leiomyomas, breast cancer, scleroderma, fibromatosis,
endometrial cancer, polycystic ovary syndrome, endometrial polyps,
benign breast disease, adenomyosis, ovarian cancer, melanoma,
prostate cancer, cancers of the colon, CNS cancers, such as glioma
or astioblastomia.
[0097] The compounds of this invention are cardioprotective and are
antioxidants, and are useful in lowering cholesterol,
triglycerides, Lp(a), and LDL levels; inhibiting or treating
hypercholesteremia, hyperlipidemia, cardiovascular disease,
atherosclerosis, peripheral vascular disease, restenosis, and
vasospasm, and inhibiting vascular wall damage from cellular events
leading toward immune mediated vascular damage. The compounds of
this invention are also useful in treating disorders associated
with inflammation or autoimmune diseases, including inflammatory
bowel disease (Crohn's disease, ulcerative colitis, indeterminate
colitis), arthritis (rheumatoid arthritis, spondyloarthropathies,
osteoarhritis), pleurisy, ischemia/reperfusion injury (e.g. stroke,
transplant rejection, myocardial infarction, etc.), asthma, giant
cell arteritis, prostatitis interstitial cystitis, uveitis,
psoriasis, multiple sclerosis, systemic lupus erythematosus and
sepsis.
[0098] The compounds of this invention are also useful in treating
or inhibiting ocular disorders including cataracts, uveitis, and
macular degeneration and in treating skin conditions such as aging,
alopecia, and acne.
[0099] The compounds of this invention are also useful in treating
or inhibiting metabolic disorders such as type-II diabetes, of
lipid metabolism, appetite (e.g. anorexia nervosa and bulimia).
[0100] Compounds in this invention are also useful in treating or
inhibiting bleeding disorders such as hereditary hemorrhagic
telangiectasia, dysfunctional uterine bleeding, and combating
hemorrhagic shock.
[0101] The compounds of this invention are useful in disease states
where amenorrhea is advantageous, such as leukemia, endometrial
ablations, chronic renal or hepatic disease or coagulation diseases
or disorders.
[0102] The compounds of this invention can be used as a
contraceptive agent, particularly when combined with a
progestin.
[0103] When administered for the treatment or inhibition of a
particular disease state or disorder, it is understood that the
effective dosage may vary depending upon the particular compound
utilized, the mode of administration, the condition, and severity
thereof, of the condition being treated, as well as the various
physical factors related to the individual being treated. Effective
administration of the compounds of the invention may be given at an
oral dose of from about 0.1 mg/day to about 1,000 mg/day.
Preferably, administration will be from about 10 mg/day to about
600 mg/day, more preferably from about 50 mg/day to about 600
mg/day, in a single dose or in two or more divided doses. The
projected daily dosages are expected to vary with route of
administration.
[0104] Such doses may be administered in any manner useful in
directing the active compounds herein to the recipient's
bloodstream, including orally, via implants, parentally (including
intravenous, intraperitoneal, intraarticularly and subcutaneous
injections), rectally, intranasally, topically, ocularly (via eye
drops), vaginally, and transdermally.
[0105] Oral formulations containing the active compounds of this
invention may comprise any conventionally used oral forms,
including tablets, capsules, buccal forms, troches, lozenges and
oral liquids, suspensions or solutions. Capsules may contain
mixtures of the active compound(s) with inert fillers and/or
diluents such as the pharmaceutically acceptable starches (e.g.
corn, potato or tapioca starch), sugars, artificial sweetening
agents, powdered celluloses, such as crystalline and
microcrystalline celluloses, flours, gelatins, gums, etc. Useful
tablet formulations may be made by conventional compression, wet
granulation or dry granulation methods and utilize pharmaceutically
acceptable diluents, binding agents, lubricants, disintegrants,
surface modifying agents (including surfactants), suspending or
stabilizing agents, including, but not limited to, magnesium
stearate, stearic acid, talc, sodium lauryl sulfate,
microcrystalline cellulose, carboxymethylcellulose calcium,
polyvinylpyrrolidone, gelatin, alginic acid, acacia gum, xanthan
gum, sodium citrate, complex silicates, calcium carbonate, glycine,
dextrin, sucrose, sorbitol, dicalcium phosphate, calcium sulfate,
lactose, kaolin, mannitol, sodium chloride, talc, dry starches and
powdered sugar. Preferred surface modifying agents include nonionic
and anionic surface modifying agents. Representative examples of
surface modifying agents include, but are not limited to, poloxamer
188, benzalkonium chloride, calcium stearate, cetostearl alcohol,
cetomacrogol emulsifying wax, sorbitan esters, colloidol silicon
dioxide, phosphates, sodium dodecylsulfate, magnesium aluminum
silicate, and triethanolamine. Oral formulations herein may utilize
standard delay or time release formulations to alter the absorption
of the active compound(s). The oral formulation may also consist of
administering the active ingredient in water or a fruit juice,
containing appropriate solubilizers or emulsifiers as needed.
[0106] In some cases it may be desirable to administer the
compounds directly to the always in the form of an aerosol.
[0107] The compounds of this invention may also be administered
parenterally or intraperitoneally. Solutions or suspensions of
these active compounds as a free base or pharmacologically
acceptable salt can be prepared in water suitably mixed with a
surfactant such as hydroxy-propylcellulose. Dispersions can also be
prepared in glycerol, liquid polyethylene glycols and mixtures
thereof in oils. Under ordinary conditions of storage and use,
these preparations contain a preservative to inhibit the growth of
microorganisms.
[0108] The pharmaceutical forms suitable for injectable use include
sterile aqueous solutions or dispersions and sterile powders for
the extemporaneous preparation of sterile injectable solutions or
dispersions. In all cases, the form must be sterile and must be
fluid to the extent that easy syringability exists. It must be
stable under the conditions of manufacture and storage and must be
preserved against the contaminating action of microorganisms such
as bacteria and fungi. The carrier can be a solvent or dispersion
medium containing, for example, water, ethanol, polyol (e.g.,
glycerol, propylene glycol and liquid polyethylene glycol),
suitable mixtures thereof, and vegetable oils.
[0109] For the purposes of this disclosure, transdermal
administrations are understood to include all administrations
across the surface of the body and the inner linings of bodily
passages including epithelial and mucosal tissues. Such
administrations may be carried out using the present compounds, or
pharmaceutically acceptable salts thereof, in lotions, creams,
foams, patches, suspensions, solutions, and suppositories (rectal
and vaginal).
[0110] Transdermal administration may be accomplished through the
use of a transdermal patch containing the active compound and a
carrier that is inert to the active compound, is non toxic to the
skin, and allows delivery of the agent for systemic absorption into
the blood stream via the skin. The carrier may take any number of
forms such as creams and ointments, pastes, gels, and occlusive
devices. The creams and ointments may be viscous liquid or
semisolid emulsions of either the oil-in-water or water-in-oil
type. Pastes comprised of absorptive powders dispersed in petroleum
or hydrophilic petroleum containing the active ingredient may also
be suitable. A variety of occlusive devices may be used to release
the active ingredient into the blood stream such as a
semi-permeable membrane covering a reservoir containing the active
ingredient with or without a carrier, or a matrix containing the
active ingredient. Other occlusive devices are known in the
literature.
[0111] Suppository formulations may be made from traditional
materials, including cocoa butter, with or without the addition of
waxes to alter the suppository's melting point, and glycerin. Water
soluble suppository bases, such as polyethylene glycols of various
molecular weights, may also be used.
[0112] The preparation of representative examples of this invention
is described below. Nomenclature for compounds of this invention
were obtained by inputting the structure into ChemDraw5.RTM. or
ChemDraw Ultra.RTM. and naming with the "convert structure to name"
tool.
Synthesis of Compounds from Scheme 1
2-Hydroxy-3-iodo-5-methoxy-benzaldehyde 1
[0113] To a solution of 2-hydroxy-5-methoxy-benzaldehyde (15.97 g,
104.9 mmole) in 375 mL dichloromethane at -15.degree. C. was added
tetraethylammonium diacetoxyiodate (48.06 g, 128.1 mmole) over 15
minutes. After stirring overnight, an additional amount of
tetraethylammonium diacetoxyiodate (46.93 g, 125.1 mmole) was added
over 15 minutes. The reaction was stirred for an additional 12
hours, concentrated, and added to 2N HCl. The mixture was extracted
into ethyl acetate and the combined organic phases were washed with
saturated sodium bicarbonate, water, brine, and dried with
magnesium sulfate. The organic phases were concentrated in vacuo
and the residue was loaded on to silica gel and chromatographed
with silica gel (hexanes:ethyl acetate, 9:1) to afford 3.47 g
(11.9%) of iodide as a yellow solid: Mp=103-105.degree. C.; .sup.1H
NMR (DMSO-d.sub.6) .delta. 11.3 (s, 1H), 9.73 (s, 1H), 7.60 (d, 1
H, J=3.0 Hz,), 7.07 (d, 1 H, J=3.1 Hz), 3.83 (s, 3H).
5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-carbaldehyde 2
[0114] A solution of iodo benzaldehyde 1 (2.11 g, 7.59 mmole),
4-ethynyl-1-methoxy-benzene (1.20 g, 9.11 mmole),
dichlorobis(triphenylphosphine)palladium(II) (0.501 g, 0.714
mmole), copper iodide (0.261 g, 1.37 mmole), in 40 mL
dimethylformamide, and 40 mL piperidine was stirred at 60.degree.
C. for 5 hours. The brown reaction mixture was poured into 2H HCl,
and extracted with diethyl ether. The combined organic phases were
washed with saturated sodium bicarbonate, water, brine, and dried
with magnesium sulfate The organic phases were concentrated and the
residue was loaded on to silica get and chromatographed with silica
gel (hexanes:ethyl acetate, 95:5) to afford 1.31 g (61%) of
aldehyde 2 as a yellow solid: Mp=218-220.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 10.4 (s, 1 H), 7.93 (d, 2 H, J=8.7 Hz), 7.55
(d, 1 H, J=2.8 Hz), 7.34 (s, 1 H), 7.33 (s, 1 H), 7.09 (d, 2 H,
J=8.7 Hz), 3.87 (s, 3 H), 3.84 (s, 3 H); MS 283 (M+H).sup.+.
[5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-methanol 3
[0115] Sodium borohydride (0.106 g, 2.73 mmole) was added to a
solution of aldehyde 2 (0.700, 2.48 mmole) in ethanol (24 mL) and
tetrahydrofuran (12 mL). After 1.5 hours stirring at room
temperature under nitrogen, the reaction was concentrated. To the
residue was added 2N HCl producing a white precipitate which was
extracted into ethyl acetate. The combined organic phases were
washed with saturated sodium bicarbonate, water, brine, and dried
with magnesium sulfate. The organic phases were concentrated and
the residue was loaded on to silica gel and chromatographed with
silica gel (hexanes:ethyl acetate, 9:1) to afford 0.810 g (98%) of
benzyl alcohol as a white solid: Mp=128-130.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 7.85 (d, 2 H, J=8.7 Hz), 7.19 (s, 1 H), 7.06
(d, 2 H, J=8.7 Hz), 7.00 (d, 1 H, J=2.5 Hz), 6.88 (d, 1 H, J=2.1
Hz), 3.82 (s, 3 Hz), 3.79 (s, 3 H); MS, 285 (M+H).sup.+.
7-Bromomethyl-2-(4-hydroxy-phenyl)-benzofuran-5-ol 4
[0116] Benzyl Alcohol 3 (0.500 g, 1.759 mmole) was dissolved in
dichloromethane (50 mL) and cooled to -78.degree. C. in dry
ice/acetone bath. To this solution, boron tribromide (1.0 M in
dichloromethane), (7.04 mL, 7.05 mmole) was added drop wise over 15
minutes. After 30 minutes, the dark orange solution was allowed to
come to room temperature and reacted for an additional 4 hours. The
solution was concentrated and added to saturated sodium bicarbonate
and extracted with ethyl acetate. Organic layers were combined and
washed with water, brine, and dried over magnesium sulfate. The
organic phases were concentrated and the residue was loaded on the
silica gel and chromotographed with silica gel (hexanes:ethyl
acetate, 7:3) to afford 0.495 g (88%) of benzyl bromide 4 as a
white solid: Mp=337-339.degree. C.; .sup.1H NMR (DMSO-d.sub.6)
.delta. 7.90 (s, 2 H), ), 7.74 (d, 2 H, J=8.8 Hz), 7.06 (s, 1 H),
6.89 (d, 2 H, J=8.7 Hz), 6.86 (d, 1 H, J=2.5 Hz), 6.77 (d, 1 H,
J=2.2 Hz); MS 317/319 (M+H).sup.+.
[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-acetonitrile 5
[0117] To a solution of benzyl bromide 4 (0.0758 g, 0.238 mmole) in
5 mL dimethylformamide was added pulverized potassium cyanide
(0.0232 g, 0.3563 mmole) and 18-crown-6 ether (0.100 g, 0.378
mmole). After stirring at 80.degree. C. for 2 hours, the reaction
mixture was cooled and poured into water and extracted with ethyl
acetate. The combined organic phases were washed with saturated
sodium bicarbonate, water, brine, and dried with magnesium sulfate.
The organic phases were concentrated and the residue was loaded on
to silica gel and chromatographed with silica gel (hexanes:ethyl
acetate, 9:1) to afford 0.046 g (82%) of benzyl nitrile 5 as a
yellow solid: Mp=128-130.degree. C.; .sup.1H NMR (DMSO-d.sub.6)
.delta. 7.85 (d, 2 H, 8.7 Hz), 7.19 (s, 1 H), 7.06 (d, 2 H, J=8,7
Hz), 7.00 (d 1 H, J=2.5Hz), 6.88 (d, 1 H, J=2.1 Hz), 3.82 (s, 3
Hz), 3.79 (s, 3 H); MS, 285 (M+H).sup.+
2-(4-Hydroxy-phenyl)-7-methoxymethyl-benzofuran-5-ol 6
[0118] Cmpd 6 was prepared under the same conditions as 7, infra,
but replacing ethanol with methanol, yielding methyl ether 6 as a
white solid: Mp 186-188.degree. C.; .sup.1H NMR (DMSO-d.sub.6)
.delta. 9.82 (br s, 1 H), 9.12 (br s, 1 H), 7.69 (d, 2 H, J=8.5
Hz), 7.03 (s, 1 H), 6.87 (d, 2 H, J=8.4 Hz), 6.82 (d, 1 H, J=2.2
Hz), 6.68 (d, 1 H, J=2.0 Hz), 4.67 (s, 2 H), 3.36 (s, 3 H); MS 269
(M-H).sup.+
7-Ethoxymethyl-2-(4-hydroxy-phenyl)-benzofuran-5-ol 7
[0119] To a solution of benzyl bromide 4 (0.05 g, 0.159 mmole) in 5
mL ethanol was added potassium hydroxide (0.350 g, 0.627 mmole).
After stirring at R.T. for 1 hour, the solvent was evaporated and
the residue was poured into water and extracted with ethyl acetate.
The combined organic phases were washed with saturated sodium
bicarbonate, water, brine, and dried with magnesium sulfate. The
organic phases were concentrated and the residue was loaded on to
silica gel and chromatographed on silica gel (hexanes:ethyl
acetate, 9:1) to afford 0.039 g (51%) of ethyl ether 7 as a tan
solid: Mp=166-168.degree. C., .sup.1H NMR (DMSO-d.sub.6)
.delta.9.82 (br s, 1 H), 9.12 (bs, 1 H), 7.70 (d, 2 H, J=8.6 Hz),
7.02 (s, 1 H), 6.86 (d, 2 H, J=8.6 Hz), 6.81 (d, 1 H, J=2.1 Hz),
6.69 (d, 1 H, J=2.2 Hz), 4.71 (s, 2 H), 3.56 (z, 2 H, J=7.2 Hz),
1.18 (t, 3 H, J=7.2 Hz); MS 283 (M-H).sup.-
2-(4-Hydroxy-phenyl)-7-isopropoxymethyl benzofuran-5-ol 8
[0120] Cmpd 8 was prepared under the same conditions as cpd 7
replacing EtOH with iPrOH isopropanol, yielding isopropyl ether 8
as a white solid: Mp=195-197.degree. C.; .sup.1H NMR DMSO-d.sub.6)
.delta. 9.82 (br s, 1 H), 9.11 (br s, 1 H), 7.69 (d, 2 H, J=8.5
Hz), 7.02 (s, 1 H), 6.86 (d, 2 H, J=8.5 Hz), 6.79. (d, 1 H, J=2.2
Hz), 6.70 (d, 1 H, J=2.0 Hz), 4.71 (s, 2 H), 3.73 (m, 1 H), 1.19
(d, 6 H, J=6.1 Hz); MS 297 (M-H).sup.-
2-(4-Hydroxy-phenyl)-7-methyl-benzofuran-5-ol 9
[0121] To a solution of benzyl bromide 4 (0.036 g, 0.113 mmole) in
2 mL methanol was added 5% Palladium on Carbon (0.100 g). After
stirring at R.T. for 20 minutes, the mixture was filtered through
glass wool and loaded on to silica gel and chromatographed with
silica gel (hexanes:ethyl acetate, 9:1) to afford 0.019 g (70%) of
methyl compound 9 as white solid: Mp=218-220.degree. C.; .sup.1H
NMR (DMSO-d.sub.6) .delta. 9.81 (br s, 1 H), 9.01 (br s, 1 H), 7.69
(d, 2 H, J=8.5 Hz), 6.99 (s, 1 H), 6.86 (d, 2 H, J=8.5 Hz), 6.70
(d, 1 H, J=2.3 Hz), 6.51 (d, 1 H, J=2.2 Hz), 2.41 (s, 3 H); MS 230
(M-H).sup.-
2-(4-Hydroxy-phenyl)-7-methylsulfanylmethyl-benzofuran-5ol 10
[0122] To a solution of benzyl bromide 4 (0.052 g, 0.161 mmole) in
5 mL methanol was added sodium thiomethoxide (0.013 g, 0.177
mmole). After stirring at R.T. for 1 hour, the solvent was
evaporated and the residue was poured into water and extracted with
ethyl acetate. The combined organic phases were washed with
saturated sodium bicarbonate, water, brine, and dried with
magnesium sulfate. The organic phases were concentrated and the
residue was loaded on to silica gel and chromatographed with silica
gel (hexanes:ethyl acetate, 4:1) to afford 0.025 g (54%) of
thioether 10 as a white solid: Mp=188-190.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.82 (s, 1 H), 9.14 (s, 1 H), 7.69 (d, 2 H,
J=8.5 Hz), 7.01 (s, 1 H), 6.86 (d, 2 H, J=8.5 Hz), 6.77 (d, 1H,
J=2.1 Hz), 6.63 (d, 1 H, J=2.1 Hz), 3.91 (s, 2 H), 2.05 (s, 3 H);
MS 285 (M-H).sup.-
7-Ethylsulfanylmethyl-2-(4-hydroxy-phenyl)-benzofuran-5-ol 11
[0123] Compound 11 was prepared under the same conditions as 10,
except that sodium thiomethoxide was replaced with sodium
thioethoxide, yielding 0.041 g (92%) of thioether 11 as a light
white solid: Mp=181-183.degree. C.; .sup.1H NMR (DMSO-d.sub.6)
.delta. 9.83 (s, 1 H), 9.14 (s, 1 H), 7.70 (d, 2 H, J=8.4 Hz), 7.02
(s, 1 H), 6.87 (d, 2 H, J=8.5 Hz), 6.76 (d, 1H, J=2.0 Hz), 6.65 (d,
1 H, J=2.1 Hz), 3.95 (s, 2 H), 2.49 (q, 2 H, J=7.3 Hz), 1.19 (t, 3
H, J=7.3 Hz); MS 299 (M-H).sup.-
2-(4-Hydroxy-phenyl)-7-phenylsulfanylmethyl-benzofuran-5-ol 12
[0124] Compound 12 was prepared under the same conditions as 10,
except that sodium thiophenoxide was used as the nucleophile,
yielding 0.069 g (76%) of thioether 12 as a light white solid:
Mp=175-177.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.84 (s,
1 H), 9.13 (s, 1 H), 7.67 (d, 2 H, J=8.5 Hz), 7.39 (d, 2 H, J=7.6
Hz), 7.29 (t, 2 H, J=7.4 Hz), 7.17 (t, 1 H, J=7.4 Hz), 7.00 (s, 1
H), 6.85 (d, 2 H, J=8.5 Hz), 6.76 (d, 1H, J=2.2 Hz), 6.67 (d, 1 H,
J=2.2 Hz), 4.45 (s, 2 H); MS 347 (M-H).sup.-
2-(4-Hydroxy-phenyl)-7-methanesulfinylmethyl-benzofuran-5-ol 13 and
2-(4--Hydroxy-phenyl)-7-methanesulfonylmethyl-benzofuran-5-ol
14
[0125] To a solution of 10 (0.070 g, 0.245 mmole) in 5 mL THF was
added mCPBA (0.058 g, 0.257 mmole). After stirring at rt for 2
hour, the solvent was evaporated and the residue was poured into
10% sodium sulfite and extracted into ethyl acetate. The combined
organic phases were washed with saturated sodium bicarbonate,
water, brine, and dried with magnesium sulfate. The organic phases
were concentrated and the residue was loaded on to silica gel and
chromatographed on silica gel (hexanes:ethyl acetate, 1:1) to
afford 0.050 g (68%) of sulfoxide 13 as a tan solid and 0.012 g
(16%) of sulfone 14 as a light white solid.
[0126] 13: Mp=234-236.degree. C.; .sup.1H NMR (DMSO-d.sub.6)
.delta. 9.85 (s, 1 H), 9.25 (s, 1 H), 7.73 (d, 2 H, J=8.5 Hz), 7.05
(s 1 H), 6.87 (m, 3 H), 6.67 (d, 1 H, J=2.1 Hz), 4.34 (d, 1 H,
J=12.9 Hz), 4.20 (d, 1 H, J=12.9 Hz), 2.57 (s, 3 H); MS 301
(M-H).sup.-
[0127] 14: Mp=245-247.degree. C.; .sup.1H NMR (DMSO-d.sub.6)
.delta. 9.86 (s, 1 H), 9.31 (s, 1 H), 7.75 (d, 2 H, J=8.5 Hz), 7.06
(s, 1 H), 6.90 (d, 1 H, J=2.2 Hz), 6.87 (d, 2 H, J=8.5 Hz), 6.78
(d, 1 H, J=2.2 Hz), 4.71 (s, 2 H), 3.5 (s, 3 H); MS 317
(M-H).sup.-
Synthesis of Compounds from Scheme 2
2-(4-Hydroxy-phenyl)-7-thiocyanatomethyl-benzofuran-5-ol 15
[0128] Compound 15 was was prepared under the same conditions as 10
except that sodium thiocyanate was used as the nucleophile,
yielding 0.021 g (78%) of thioether 15 as a light white solid:
Mp=190-192.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.86 (s,
1 H), 9.32 (s, 1 H), 7.75 (d, 2 H, J=8.6 Hz), 7.07 (s, 1 H), 6.88
(m, 3 H), 6.74 (d, 1 H, J=2.3 Hz), 4.60 (s, 2 H), MS 296
(M-H).sup.-
2-(4-Hydroxy-phenyl)-7-imidazol-1-ylmethyl-benzofuran-5-ol 16
[0129] To a solution of benzyl bromide 4 (0.070 g, 0.215 mmole) in
10 mL DMF was added imidazole (0.030 g, 0.437 mmole). After
stirring at 60.degree. C. for 3 hours, the reaction mixture was
poured into water and extracted with ethyl acetate. The combined
organic phases were washed with saturated sodium bicarbonate,
water, brine, and dried with magnesium sulfate. The organic phases
were concentrated and the residue was loaded on to silica gel and
chromatographed with silica gel (hexanes:ethyl acetate, 9:1) to
afford 0.059 g (88%) of imidazole 16 as a light tan solid:
Mp=269-271.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.88 (s,
1 H), 9.24 (s, 1 H), 7.88 (s, 1 H), 7.72 (d, 2 H, J=8.6 Hz), 7.26
(s, 1H), 7.04 (s, 1 H), 6.93 (s, 1 H), 6.88 (d, 2 H, J=8.7 Hz),
6.83 (d, 1 H, J=2.3 Hz), 6.50 (d, 1 H, J=2.3 Hz), 5.46 (s, 2 H); MS
305 (M-H).sup.-
7-Bromomethyl-5-methoxy-2-(4-methoxy-phenyl)-benzofuran 17
[0130] Benzyl Alcohol 3 (1.02 g, 3.59 mmole) was dissolved in
dichloromethane (70 mL) and cooled to -78.degree. C. in an dry
ice/acetone bath. Boron tribromide (1.0 M in dichloromethane, (3.95
mL, 3.95 mmole) was added drop wise over 15 minutes. After 30
minutes, the light orange solution was allowed to come to room
temperature and reacted for an additional four hours. The solution
was concentrated and added to saturated sodium bicarbonate, and
extracted with ethyl acetate. Organic layers were combined and
washed with water and brine, dried over magnesium sulfate. The
organic phases were concentrated and the residue was loaded on to
silica gel and chromotographed with silica gel (hexanes:ethyl
acetate, 9:1) to afford 2.91 g (81%) of benzyl bromide 17 as a
white solid: Mp=158-160.degree. C. .sup.1H NMR (DMSO-d.sub.6)
.delta. 7.68 (d, 2 H, J=8.8 Hz), 7.23 (s, 1 H), 7.11 (d, 2 H, J=2.5
Hz), 7.09 (d, 2 H, J=8.9 Hz), 6.99 (d, 1 H, J=2.5 Hz), 4.96 (s, 2
H), 3.82 (s, 3 H), 3.80 (s, 3 H).
(5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-acetonitrile
18
[0131] To a solution of benzyl bromide 17 (0.640 g, 1.843 mmole) in
100 mL dimethylformamide was added pulverized potassium cyanide
(0.186 g, 2.76 mmole) and 18-crown-6 ether (0.786 g, 2.965 mmole).
After stirring at 80.degree. C. for 2 hours, the reaction mixture
was cooled and poured into water and extracted with ethyl acetate.
The combined organic phases were washed with saturated sodium
bicarbonate, water, brine, and dried with magnesium sulfate. The
organic phases were concentrated and the residue was loaded on to
silica gel and chromatographed with silica gel (hexanes:ethyl
acetate, 9:1) to afford 0.529 g (98%) of acetonitrile 18 as a white
solid: Mp=149-150.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta.
7.87 (d, 2 H, J=8.8 Hz), 7.26 (s, 1 H), 7.12 (d, 1 H, J=2.4 Hz), ),
7.10 (d, 2 H, J=8.7 Hz), 6.88 (d, 1 H, J=2.4 Hz), 4.42 (s, 2 H),
3.82 (s, 3 H), 3.81 (s, 3 H); MS 294 (M+H).sup.+
2-[5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-propionitrile
19
[0132] To a solution of acetonitrile 18 (0.200 g, 0.682 mmole) in
10 mL dimethylformamide was added pulverized potassium hydroxide
(0.046 g, 0.818 mmole) and methyl iodide (0.161 g, 0.818 mmole).
After stirring at rt for 2 hours, the orange reaction mixture was
poured into water and extracted with ethyl acetate. The combined
organic phases were washed with saturated sodium bicarbonate,
water, brine, and dried with magnesium sulfate. The organic phases
were concentrated and the residue was loaded on to silica gel and
chromatographed with silica gel (hexanes:ethyl acetate, 95:5) to
afford 0.087 g (42%) of propionitrile 19 as a white solid. Used as
is for conversion to 21, infra.
2-[5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-2-methyl-propionitrile
20
[0133] To a solution of acetonitrile 18 (0.054 g, 0.184 mmole) in 5
mL dimethylformamide was added pulverized potassium hydroxide
(0.024 g, 0.390 mmole) and methyl iodide (0.0552 g, 0.0391 mmole).
After stirring at rt for 2 hours the reaction mixture was poured
into water and extracted with ethyl acetate. The combined organic
phases were washed with saturated sodium bicarbonate, water, brine,
and dried with magnesium sulfate. The organic phases were
concentrated and the residue was loaded on to silica gel and
chromatographed with silica gel (hexanes:ethyl acetate, 95:5) to
afford 0.046 g (78%) of methyl-propionitrile 20 as a yellow solid:
Mp=146-148.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 7.87 (d,
2 H, J=8.8 Hz), 7.26 (s, 1 H), ), 7.15 (d, 1 H, J=2.4 Hz), 7.10 (d,
2 H, J=8.9 Hz), 6.86 (d, 1 H, J=2.4 Hz), 3.82 (s, 3 H), 3.81 (s, 3
H), 1.89 (s, 6 H); MS 322 (M+H).sup.+
2-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-propionitrile
21
[0134] Compound 21 was prepared by heating 19 with excess Pyr-HCl
at 200.degree. C. until reaction judged complete by TLC (<1 h).
The reaction was allowed to cool and partitioned between 2 N HCl aq
and EtOAc. The EtOAc was washed with saturated NaHCO.sub.3 aq.,
brine and dried over MgSO.sub.4. Chromatography on silica gel
(EtOAC/hexanes) yielded the desired product as a yellow solid:
Mp=183-185.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.88 (br
s, 1 H), 9.37 (br s, 1 H), 7.73 (d, 2 H, J=8.6 Hz), 7.07 (s, 1 H),
6.89 (m, 3 H), 6.73 (d, 1 H, J=2.2 Hz), 4.63 (q, 1 H, J=7.2 Hz),
1.68 (d, 3 H, J=7.2 Hz); MS 278 (M-H).sup.-
2-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-2-methyl-propionitrile
22
[0135] Compound 22 was prepared similarly to 21, yielding the
product as a light yellow solid: Mp=284.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.89 (br s, 1 H), 9.38 (br s, 1 H), 7.72 (d,
2 H, J=8.6 Hz), 7.08 (s, 1 H), 6.90 (d, 2 H, J=8.5 Hz), 6.89 (d, 1
H, J=2.4 Hz), 6.77 (d, 1 H, J=2.3 Hz), 1.87 (s, 6 H); MS, 294
(M+H).sup.+
5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-carboxylic acid 23
[0136] To a solution of aldehyde 2 (0.200 g, 0.708 mmole) in 20 mL
THF was added a solution of sodium chlorite (0.370 g, 3.08 mmole)
and sodium dihydrogen phosphate (0.300 g, 3.32 mmole) in water and
amylene (6 mL, 57 mmole). After stirring at room temperature for 2
hours, the THF evaporated and the was residue poured into water and
extracted with ethyl acetate. The combined organic phases were
washed with saturated sodium bicarbonate, water, brine, and dried
with magnesium sulfate. The organic phases were concentrated and
the residue was loaded on to silica gel and chromatographed with
silica gel (hexanes:ethyl acetate, 9:1) to afford 0.081 g (42%) of
acid 23 as a white solid: Mp=218-220.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 7.85 (d, 2 H, J=8.7 Hz), 7.41 (d, 2 H, J=2.7
(s, 3 H); MS 299 (M+H).sup.30. Product was contaminated with some
3-Cl Compound.
5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-carboxylic acid 24
[0137] To acid 23 (0.075 g, 0.250 mmole) was added pyridine-HCl
(5.1 g, 43.3 mmole). After stirring at 200.degree. C. for 30
minutes, the mixture was cooled to rt, poured into 2N HCl aq. and
extracted with ethyl acetate. The combined organic phases were
washed with saturated sodium bicarbonate, water, brine, and dried
with magnesium sulfate. The organic phases were concentrated and
the residue was loaded on to silica gel and chromatographed with
silica gel (hexanes:ethyl acetate, 1:1) to afford 0.052 g (77%) of
acid 24 as a white solid: Mp=260-262.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 13.3 (br s, 1 H), 9.79 (br s, 1 H), 9.46 (br
s, 1 H), 7.91 (d, 2 H, J=8.7 Hz), 7.30 (d, 1 H, J=2.4 Hz), 7.11 (s,
1 H), 7.08 (d, 1 H, J=2.4 Hz), 6.98 (d, 2 H, J=8.9 Hz); MS 269
(M-H).sup.- Product was still contaminated with some 3-Cl
compound.
7-Hydroxymethyl-2-(4-hydroxy-phenyl)-benzofuran-5-ol 25
[0138] Acid 24 (0.030 g 0.112 mmole) in 5 mL THF was added a
solution of Borane-THF complex (2.0 mL, 2.0 mmole) in THF. After
stirring at 65.degree. C. for 6 hours, the THF was evaporated and
the residue was poured into 2N HCl and extracted with ethyl
acetate. The combined organic phases were washed with saturated
sodium bicarbonate, water, brine, and dried with magnesium sulfate.
The organic phases were concentrated and the residue was separated
by HPLC (70:30, H.sub.2O/AcCN) to afford 0.011 g (36%) of benzyl
alcohol 25 as a white solid: Mp=258-260.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.81 (s, 1 H), 9.45 (s, 1 H), 7.70 (d, 2 H,
J=8.9 Hz), 7.00.(s, 1 H), 6.86 (d, 2 H, J=8.7 Hz), 6.76 (s, 2 H),
5.27 (m, 1 H), 4.75 (d, 2 H, J=5.6 Hz); MS 255 (M-H).sup.-
5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-carbaldehyde oxime
26
[0139] To a solution of hydroxylamine hydrochloride (0.119 g, 1.59
mmole) and pyridine (0.134 mL, 1.59 mmole) in 14 mL ethanol was
added aldehyde 2 (0.300 g, 1.06 mmole). After stirring at
80.degree. C. for 1.5 hours, the solvent was evaporated and the
residue was poured into water and extracted with ethyl acetate. The
combined organic phases were washed with saturated sodium
bicarbonate, water, brine, and dried with magnesium sulfate. The
organic phases were concentrated and the residue was loaded on to
silica gel and chromatographed with silica gel (hexanes:ethyl
acetate, 1:1) to afford 0.213 g (67%) of oxime 26 as a white solid:
Mp=185-187.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 11.6 (s,
1 H), 8.49 (s, 1 H), 7.88 (d 2 H, J=8.9 Hz), 7.24 (s, 1 H), 7.17
(d, 1 H, J=2.8 Hz), 7.10-7.09 (m, 3 H, J=9.2 Hz), 3.83 (s; 3 H),
3.81 (s, 3 H), MS 298 (M+H).sup.+
[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-carbonitrile
27
[0140] To oxime 26 (0.090 g, 0.303 mmole) was added Pyr-HCl (8.0 g,
69.3 mmole). After stirring at 200.degree. C. for 30 minutes, the
mixture was cooled to R.T., added to 2N HCl and extracted with
ethyl acetate. The combined organic phases were washed with
saturated sodium bicarbonate, water, brine, and dried with
magnesium sulfate. The organic phases were concentrated and the
residue was loaded on to silica gel and chromatographed with silica
gel (hexanes:ethyl acetate, 1:1) to afford 0.039 g (51%) of
acetonitrile 27 as a tan solid: Mp>300.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.99 (br s, 1 H), 9.88 (br s, 1 H), 7.74 (d,
2 H, J=8.6 Hz), 7.27 (d, 1 H, J=2.3 Hz), 7.21 (s, 1 H), 7.07 (d, 1
H, J=2.1 Hz), 6.91 (d, 2 H, J=8.6 Hz); MS 250 (M-H).sup.-
Synthesis of Compounds from Scheme 3
5-Methoxy-2-(4-methoxy-phenyl)-7-vinyl-benzofuran 28
[0141] Methyl triphenylphosphonium bromide (0.122 g, 0.334 mmole)
was dissolved in 5 mL THF and placed in an acetone/dry ice bath at
-78.degree. C. n-Butyl lithium (0.131 mL, 0.328 mmole) was added
and the mixture was allowed to stir for -30 minutes. To this
solution was added aldehyde 3 (0.078 g, 0.278 mmole) in 3 mL THF.
After stirring at room temperature for 4 hours, the reaction
mixture was placed in an oil bath and allowed to stir overnight at
65.degree. C. The solvent was evaporated and the residue was poured
into water and extracted with ethyl acetate. The combined organic
phases were washed with saturated sodium bicarbonate, water, brine,
and dried with magnesium sulfate. The organic phases were
concentrated and the residue was loaded on to silica gel and
chromatographed with silica gel (hexanes:ethyl acetate, 95:5) to
afford 0.055 g (71%) of 28 as a white solid: Mp=182-184.degree. C.;
.sup.1H NMR (DMSO-d.sub.6) .delta. 7.67 (d, 2 H, J=8.4 Hz); 7.22
(s, 1 H), 7.08 (m, 3 H), 6.98 (d, 1 H, J=2.3 Hz), 6.30 (d, 1 H,
J=17.6 Hz), 5.69 (d, 1 H, J=11.4 Hz), 3.82 (s, 3 H), 3.80 (s, 3 H);
MS 281 (M+H).sup.+
7-Ethyl-5-methoxy-2-(4-methoxy-phenyl)-benzofuran 29
[0142] Compound 29 was prepared by dissolving 28 in MeOH, treating
with catalytic 5% Pd/C and stirring under an atmosphere of H.sub.2.
After stirring at rt under an atmosphere of H.sub.2 for 20 minutes,
the mixture was filtered through glass wool and loaded on to silica
gel and chromatographed with silica gel (hexanes:ethyl acetate) to
afford 29 as a white solid: Mp=187-189.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 7.83 (d, 2 H, J=8.7 Hz), 7.17 (s, 1 H), 7.06
(d, 2 H, J=8.8 Hz), ), 6.94 (d, 1 H, J=2.5 Hz), 6.70 (d, 1 H, J=2.4
Hz), 3.81 (s, 3 H), 3.77 (s, 3 H), 2.88 (q, 2 H, J=7.8 Hz), 1.31
(t, 3 H J=7.8 Hz); MS 283 (M+H).sup.+
7-Ethyl-2-(4-hydroxy-phenyl)-benzofuran-5-ol 30
[0143] Compound 30 was prepared by demethylation of 29 using
Pyr-HCl (method described previously for preparation of 21):
Mp=218-220.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.81 (s,
1 H), 9.02 (s, 1 H), 7.69 (d, 2 H, J=8.5 Hz), 6.99 (s, 1 H), 6.86
(d, 2 H, J=8.5 Hz), 6.70 (d, 1 H, J=2.2 Hz), 6.55 (d, 1 H, J=2.0
Hz), 2.81 (q, 2 H, J=7.5 Hz), 1.29 (t, 3 H, J=7.5 Hz); MS 255
(M+H).sup.+
7-(2,2-Dichloro-vinyl)-5-methoxy-2-(4-methoxy-phenyl)-benzofuran
31
[0144] To a solution of aldehyde 2 (0.065 g, 0.230 mmole) in 5 mL
dichloromethane was added triphenylphosphine (0.244 g, 0.929 mmole)
and carbontetrachloride (0.05 mL g, 0.484 mmole). After stirring at
rt for 4 hours, the solvent was evaporated and the residue was
poured into water and extracted with ethyl acetate. The combined
organic phases were washed with saturated sodium bicarbonate,
water, brine, and dried with magnesium sulfate. The organic phases
were concentrated and the residue was loaded on to silica gel and
chromatographed with silica gel (hexanes:ethyl acetate, 9:1) to
afford 0.071 g (88%) of 31 as a white solid: Mp=129-131.degree. C.;
.sup.1H NMR (DMSO-d.sub.6) .delta. 7.90 (d, 2 H, J=8.4 Hz), 7.54
(s, 1 H), 7.25 (s, 1 H), 7.19 (s, 2 H), 7.07 (d, 2 H, J=8.6 Hz),
3.82 (s, 3 H), 3.81 (s, 3 H); MS 349 (M+H).sup.+
7-(2,2-dichloro-vinyl)-5-hydroxy-2-(4-hydroxy-phenyl)-benzofuran-5ol
32
[0145] Compound 32 was demethylated with Pyr-HCl as described
previously for 21; Mp=217-219.degree. C., .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.87 (s, 1 H), 9.37 (s, 1 H), 7.75 (d, 2 H,
J=8.6 Hz), 7.48 (s, 1 H), 7.10 (d, 1 H, J=2.3 Hz), 7.08 (s, 1 H),
6.93 (d, 1 H, J=2.2 Hz), 6.87 (d, 2
5-Methoxy-2-(4-methoxyphenyl)-7-propenyl-benzofuran 33
[0146] Ethyl triphenylphosphonium bromide (0.319 g, 0.850 mmole)
was dissolved in 15 mL THF and placed in an acetone/dry ice bath at
-78.degree. C. n-butyl lithium (0.334 mL, 0.836 mmole) was added
and the mixture was allowed to stir for 30 minutes. To this
solution was added aldehyde 2 (0.078 g, 0.278 mmole) in 3 mL THF.
After stirring at room temperature for 4 hours, the reaction
mixture was placed in an oil bath and allowed to stir overnight at
65.degree. C. The solvent was evaporated and the residue was poured
into water and extracted with ethyl acetate. The combined organic
phases were washed with saturated sodium bicarbonate, water, brine,
and dried with magnesium sulfate. The organic phases were
concentrated and the residue was loaded on to silica gel and
chromatographed with silica gel (hexanes:ethyl acetate, 9:1) to
afford 0.187 g (90%) of 33 as a white solid: Mp=116-118.degree.
C.;; .sup.1H NMR (DMSO-d.sub.6) .delta. 7.87 (d, 2 H, J=8.6 Hz),
7.20 (s, 1 H), 7.08 (d, 2 H, J=8.6 Hz), 6.98 (d, 1 H, J=2.4 Hz),
6.85 (d, 1 H, J=2.5 Hz), 6.78 (d, 1 H, J=6.4 Hz), 3.82 (s, 3 H),
3.80 (s, 3 H), 1.99(s, 3 H); MS 295 (M+H).sup.+
5-Methoxy-2-(4-methoxy-phenyl)-7-propyl-benzofuran 34
[0147] Compound 34 was prepared by hydrogenation of 33 (Pd/C,
H.sub.2) yielding 34 as a white solid: Mp=109-111.degree. C.;
.sup.1H NMR (DMSO-d.sub.6) .delta. 7.83 (d, 2 H, J=8.6 Hz), 7.17
(s, 1 H), 7.07 (d, 2 H, J=8.5 Hz), 6.94 (d, 1 H, J=2.4 Hz), 6.70
(d, 1 H, J=2.5 Hz), 3.81 (s, 3 H), 3.76 (s, 3 H), 2.84 (t, 2 H,
J=7.8 Hz), 1.75 (q, 2 H, J=7.4 Hz), 0.96 (t, 3 H, J=7.4 Hz); MS 297
(M+H).sup.+
2-(4-Hydroxy-phenyl)-7-propyl-benzofuran-5-ol 35
[0148] Compound 35 was prepared via demethylation of 34 with
Pyr-HCl: Mp=178-180.degree. C; .sup.1H NMR (DMSO-d.sub.6) .delta.
9.81 (br s, 1 H), 9.02 (br s, 1 H), 7.67 (d, 2 H, J=8.5 Hz), 6.98
(s, 1 H), 6.87 (d, 2 H, J=8.5 Hz), 6.71 (d, 1 H, J=2.1 Hz), 6.51
(d, 1 H, J=2.1 Hz), 2.84 (t, 2 H, J=7.8 Hz), 1.75 (q, 2 H, J=7.4
Hz), 0.96 (t, 3 H, J=7.4 Hz); MS 269 (M+H).sup.+
5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-carboxylic acid
isopropyl ester 36
[0149] 1 M HCl in diethyl ether (1.20 mL, 1.20 mmole) was added to
a solution of carboxylic acid 24 (0.0246, 0.172 mmole) in
isopropanol 5 mL. After refluxing overnight, the reaction mixture
was concentrated and partitioned between water and ethyl acetate.
The combined organic phases were washed with saturated sodium
bicarbonate, water, brine, and dried with magnesium sulfate. The
organic phases were concentrated and the residue was loaded on to
silica gel and chromatographed with silica gel (hexanes:ethyl
acetate, 4:1) to afford 0.390 g (74%) of ester 36 as a light tan
solid: Mp>250.degree. C.; Calculated mass for
C.sub.18H.sub.16O.sub.5 is 312.32, found by ESI MS, 311
(M-H).sup.-; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.93 (br s, 1 H),
9.55 (br s, 1 H), 7.73(d, 2 H, J=8.6 Hz), 7.22 (d, 1 H, J=2.6 Hz),
7.17 (d, 1 H, J=2.5 Hz), 7.13 (s, 1 H), 6.90 (d, 2 H, J=8.7 Hz),
5.21 (m, 1 H), 1.42 (d, 6 H, J=6.2 Hz).
5-Hydroxy-2-(4-hydroxy-phenyl)benzofuran-7-carboxylic acid propyl
ester 37
[0150] Compound 37 was prepared under the same conditions as
described for 36 except that isopropanol was replaced by propanol,
yielding ester compound 37 as a white solid: Mp=220-222.degree. C.;
.sup.1H NMR (DMSO-d.sub.6) .delta. 9.92 (br s, 1 H), 9.54 (br s, 1
H), 7.73 (d, 2 H, J=8.6 Hz), 7.23 (d, 1 H, J=2.5 Hz), 7.17 (d, 1 H,
J=2.5 Hz), 7.13 (s, 1 H), 6.88 (d, 2 H, J=8.7 Hz),1.07 (t, 3 H,
J=7.3 Hz),), 1.81 (q, 2 H, J=7.2 Hz, J=6.7 Hz), 4.32 (t, 2 H, J=6.4
Hz); MS 311 (M-H).sup.-
5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-carboxylic acid methyl
ester 38
[0151] A solution of carboxylic acid 24 (0.35 g, 1.3 mmol) in
HCl/MeOH(10 ml) was refluxed for 2 hr. The reaction -was then
cooled, concentrated and the product was dissolved in EtOAc, washed
with sat NaHCO.sub.3, seperated dried, and concentrated to give a
solid. The solid was triturated with CH.sub.2Cl.sub.2 filtered to
give a solid (0.15 g, 47%): Mp=236-238.degree. C.; .sup.1NMR
(DMSO-d.sub.6) .delta. 9.90 (s, 1 H), 9.57 (s, 1 H), 7.73 (d, 2 H,
J=8.5 Hz), 1 H, J=2.1 Hz), 7.17 (d. 1 H, J=2.1 Hz),7.12 (s, 1 H),
6.88 (d, 2 H, J=8.5 Hz), 3.94 (s, 3 H); MS 283 (M-H).sup.-
5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-carboxylic acid ethyl
ester 39
[0152] A solution of carboxylic acid 24 (3.5 g, 13 mmol) in
HCl/EtOH(100 ml) was refluxed for 2 hr. The reaction was then
cooled, concentrated and the product was dissolved in EtOAc, washed
with sat NaHCO.sub.3, dried over MgSO.sub.4, and concentrated to
give a solid. The solid was triturated with CH.sub.2Cl.sub.2,
filtered to give the desired product (3.5 g, 92%);
Mp=221-223.degree. C.; .sup.1NMR (DMSO-d.sub.6) .delta. 9.90 (s, 1
H), 9.55(s, 1 H), 7.73 (d, 2 H, J=8.5 Hz), 7.23 (d, 1 H, J=2.1 Hz),
7.17 (d, 1 H, J=2.5 Hz), 7.12 (s, 1H), 6.88 (d, 2 H, J=8.5 Hz),
4.43-4.35 (m, 2 H), 1.41 (t, 3 H, J=7.0 Hz); MS 297
(M-H).sup.-.
Synthesis of Compounds from Scheme 4
(3-Fluoro-4-methoxy-phenylethynyl)-trimethyl-silane (not numbered
in scheme)
[0153] A solution of 2-fluoro-4-bromoanisole (2.14 g, 10.4 mmole),
dichlorobis(triphenylphosphine)palladium (II) (0.501 g, 0.304
mmole), copper iodide (0.036 g, 0.189 mmole), and 20 mL
diisopropylamine was stirred at 70.degree. C. over night in a
sealed pressure tube. The black reaction mixture was poured into 2N
HCl and extracted with ethyl acetate. The combined organic phases
were washed with saturated sodium bicarbonate, water, brine, and
dried with magnesium sulfate. The organic phases were concentrated
and the residue was loaded on to silica gel and chromatographed
with silica gel (hexanes:ethyl acetate, 95:5) to afford 2.13 g
(92%) of acetylene as a light brown low melting solid:
Mp=28-29.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 7.30 (m, 2
H), 7.15 (t, 1 H, J=8.7 Hz), 3.86 (s, 3 H), 0.217 (s, 9 H).
4-Ethynl-2-fluoro-1-methoxy-benzene (not numbered in scheme)
[0154] Pulverized potassium hydroxide (1.22 g, 18.2 mmole) was
added to a solution of TMS-acetylene compound prepared immediately,
supra, (2.31, g, 10.3 mmole) in 100 mL of methanol. The light brown
solution was allowed to stir at rt for one hour, after which, the
solvent was evaporated and partitioned between water and ethyl
acetate. The combined organic phases were washed with saturated
sodium bicarbonate, water, brine, and dried with magnesium sulfate.
The organic phases were concentrated and the residue was loaded on
to silica gel and chromatographed with silica gel (hexanes:ethyl
acetate, 4:1) to afford 1.51 g (97%) of acetylene as a light brown
brown solid: Mp=36-38.degree. C., .sup.1H NMR (DMSO-d.sub.6)
.delta. 7.35 (dd, 1 H, J=12.1 Hz, J=1.9 Hz), 7.29 (dd, 1 H, J=1.0
Hz, J=8.5 Hz), ), 7.17 (t, 1 H, J=8.7 Hz), 4.15 (s, 1 H), 3.85 (s,
3 H).
2-(3-Fluoro-4-methoxy-phenyl-5-methoxy-benzofuran-7-carboxylic acid
methyl ester 40
[0155] A solution of ester 1 (2.79 g, 9.05 mmole),
4-ethynyl-2-fluoro-1-methoxy-benzene immediately supra, (1.63 g,
10.86 mmole), dichlorobis(triphenylphosphine)palladium(II) (0.636
g, 0.906 mmole), copper iodide (0.345 g, 1.81 mmole), 40 mL
dimethylformamaide, and 40 mL piperidine was stirred at 60.degree.
C. for 5 hours. The brown reaction mixture was cooled poured into
2N HCl, and extracted with diethyl either. The combined organic
phases were washed with saturated sodium bicarbonate, water, brine,
and dried with magnesium sulfate. The organic phases were
concentrated and the residue was triturated with methanol, loaded
on to silica gel and chromatographed with silica gel (hexanes:ethyl
acetate, 95:5) to afford 2.21 g (74%) of ester 40 as a tan solid:
Mp=121-123.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 7.81-7.73
(m, 2 H), 7.46 (d, 1 H, J=2.6 Hz), 7.37 (s, 1 H), 7.37-7.31 (m, 2
H), 6.88 (d, 1 H, J=2.4 Hz), 4.42 (s, 2 H), 3.97 (s, 3H), 3.91 (s,
3 H), 3.84 (s, 3 H); MS 331 (M+H).sup.+
[2-(3-Fluoro-4-methoxy-phenyl)-5-methoxy-benzofuran-7-yl]-methanol
41
[0156] Fluoro ester 40 (1.00 g, 3.63 mmole), was dissolved in 40 mL
THF and stirred under nitrogen. To this solution was added lithium
aluminumhydride (1M in THF, 3.81 mL, 3.81 mmole) dropwise over
fifteen minutes. After stirring at rt for one half hour, the
solvent was removed and the mixture was poured into 2N HCl and
extracted with ethyl acetate. The combined organic phases were
washed with saturated sodium bicarbonate, water, brine, and dried
with magnesium sulfate. The organic phases were concentrated and
the residue was loaded on to silica gel and chromatographed with
silica gel (hexanes:ethyl acetate, 4:1) to afford 0.800 g (73%) of
benzyl alcohol 41 as a tan solid: Mp=128-130.degree. C.; .sup.1H
NMR (DMSO-d.sub.6) .delta. 7.78 (dd, 1 H, J=12.5 Hz, 2.0 Hz), 7.69
(dd, 1 H, J=8.7 Hz, 1.1 Hz), 7.29 (t, 2 H, J=8.1 Hz), 7.01 (d, 1 H,
J=2.5 Hz), 6.90 (d, 1 H, J=2.5 Hz), 5.37 (br s, 1 H), 4.81 (d, 2 H,
J=3.1 Hz), 3.90 (s, 3 H), 3.81 (s, 3 H); MS 303 (M+H).sup.+
7-Bromomethyl-2-(3-3-fluoro-4-hydroxy-phenyl)-benzofuran-5-ol
42
[0157] Compound 42 was prepared analogously to compound 4 yielding
0.200 g (36%) of 42 as a tan solid: Mp=269-271.degree. C.; .sup.1H
NMR (DMSO-d.sub.6) .delta. 10.3 (br s, 1 H), 9.34 (br s, 1 H), 7.72
(dd, 1H, J=122 Hz, 2.0 Hz), 7.68 (dd, 1 H, J=8.4 Hz, 1.5 Hz), 7.17
(t, 2 H, J=8.7 Hz), 6.88 (d, 1 H, J=2.5 Hz), 6.80 (d, 1 H, J=2.9
Hz), 4.92 (s, 2 H); MS 335/337 (M-H).sup.-
[2-(3-Fluoro-4-hydroxy-phenyl)-5-hydroxy-benzofuran-7-yl]-acetonitrile
43
[0158] Compound 43 was prepared under the same conditions as 5,
yielding 0.782 g (71%) of 43 as a cream colored solid:
Mp=242-244.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.3 (br
s, 1 H), 9.38 (br s, 1 H), 7.69 (dd, 1H, J=12.3 Hz, 2.0 Hz), 7.55
(dd, 1 H. J=8.4 Hz, J=1.4 Hz), 7.18 (s, 1 H), 7.07 (t, 1 H, J=8.6
Hz), 6.88 (d, 1 H, J=2.3 Hz), 6.75 (d, 1 H, J=2.2 Hz), 4.28 (s, 2
H); MS 282 (M-H).sup.-
[4-Chloro-5-hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-acetonitrile
43a
[0159]
[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-acetonitrile 43
(0.0650 g, 0.2390 mmole) was dissolved in acetonitile (5 mL) and
cooled in an ice bath. To this solution, was added pulverized
potassium carbonate (0.073 g, 0.527 mmole). After stirring for one
hour, N-chlorosuccinimide (0.031 g, 0.227 mmole), which was
dissolved in 0.5 mL acetonitrile, was added over one hour in three
portions and stirred overnight. The solution was poured into 0.1 N
HCl solution and the aqueous layer was extracted with ethyl
acetate. Organic layers were combined and washed with saturated
sodium bicarbonate, water, brine, and dried over magnesium sulfate.
The organic phases were concentrated and the residue was
chromatographed by HPLC with (water:acetonitrile, 1:1) to afford
0.031 g (43%) of chloro 59 as a tan solid: mp 242-244.degree. C.;
Calculated mass for C.sub.16H.sub.10NO.sub.3Cl is 299.71, found by
FI MS, 298/300 (M+H).sup.-; .sup.1H NMR (DMSO-d.sub.6) .delta.
10.07 (s, 1 H), 9.96 (s, 1 H) 7.80 (d, 2 H, 8.6 Hz)., 7.19 (s, 1
H), 6.91 (t, 3 H, J=8.1 Hz), 6.31 (s, 2 H).
2-3-Fluoro-4-methoxy-phenyl)-5-methoxy-benzofuran-7-carboxylic acid
44
[0160] 2N NaOH (20 mL, 40 mmole) was added to a solution of ester
40 (0.766, 2.301 mmole) in 60 mL 50:50 methanol/THF and refluxed at
70.degree. C. for one half hour. The reaction mixture was cooled
and poured into 2N HCl (25 mL, 50 mmole). The white precipitate was
extracted into ethyl acetate and the combined organic phases were
washed with saturated sodium bicarbonate, water, brine, and dried
with magnesium sulfate. The organic phases were concentrated and
the residue was loaded on to silica gel and chromatographed with
silica gel (hexanes:ethyl acetate, 1:1) to afford 0.710 g (98%) of
acid 44 as a tan solid: Mp=254-256.degree. C.;; .sup.1H NMR
(DMSO-d.sub.6) .delta. 13.3 (br s, 1 H), 7.75 (dd, 1 H, J=2.0 Hz,
J=1.9 Hz), 7.70 (d, 1 H, J=9.3 Hz), 7.42 (d, 1 H, J=2.6 Hz), 7.38
(s, 1 H), 7.34 (m, 2 H), 3.91 (s, 3 H), 3.84 (s, 3 H); MS 315
(M-H).sup.-
2-(3-Fluoro-4-methoxy-phenyl)-5-methoxy-benzofuran-7-carboxylic
acid methoxy-methyl-amide 45
[0161] A solution of 44 (0.400 g, 1.27 mmole), N,O
dimethylhydroxylamine hydrochloride (0.247 g, 2.53 mmole), DMAP
(0.309 g, 2.53 mmole),and EDCl (0.364 g, 1.90 mmole), in 40 mL
dimethylformamide was stirred at rt for 2 hours. The reaction
mixture was poured into water and extracted with ethyl acetate. The
combined organic phases were washed with saturated sodium
bicarbonate, water, brine, and dried with magnesium sulfate. The
organic phases were concentrated and the residue was loaded on to
silica gel and chromatographed with silica gel (hexanes:ethyl
acetate, 7:3) to afford 0.290 g (63%) of amide 45 as a tan solid:
Mp=100-102.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 7.74 (dd,
1H, J=2.0 Hz), 7.66 (d, 1 H, J=8.6 Hz), 7.37 (s, 1 H), 7.31 (t, 1
H, J=8.7 Hz), 7.24 (d, 1 H, J=2.6 Hz), 6.93 (d, 1 H, J=2.6 Hz),
3.90 (s, 3 H), 3.82 (s, 3 H), 3.59 (br s, 3 H), 3.30 (s, 3 H); MS
360 (M+H).sup.+
2-(3-Fluoro-4-methoxy-phenyl)-5-methoxy-benzofuran-7-carbaldehyde
46
[0162] Compound 46 was prepared by LiAlH.sub.4 reduction of the
amide under similar conditions as described previously for the
preparation of 41 yielding 0.208 g (94%) of 46 as a yellow solid:
Mp=161-163.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.4 (br
s, 1 H), 7.87 (dd, 1 H, J=12.5 Hz, 2.0 Hz), 7.78 (d, 1 H, J=7.4 Hz,
1.0 Hz), 7.53 (d, 1 H, J=2.4 Hz), 7.43 (s, 1 H), 7.35 (d, 1 H,
J=2.9 Hz), 7.34 (t, 1 H, J=8.9 Hz), 3.92 (s, 3 H), 3.87 (s, 3 H);
MS 301 (M+H).sup.+
2-(3-Fluoro-4-methoxy-phenyl)-5-methoxy-benzofuran-7-carbaldehyde
oxime 47
[0163] Compound 47 was prepared under the same conditions as
described for 26, yielding 0.163 g (85%) of 47 as a light yellow
solid: Mp=208-210.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta.
11.6 (br s, 1 H), 8.52 (br s, 1 H), 7.83 (dd, 1 H, J=12.5 Hz, 2.0
Hz), 7.74 (d, 1 H, J=8.6 Hz), 7.34 (s, 1 H), 7.30 (t, 1 H, J=8.9
Hz), 7.18 (d, 1 H, J=2.5 Hz), 7.12 (d, 1 H, J=2.5 Hz), 3.91 (s, 3
H), 3.81 (s, 3 H); MS, 316 (M+H).sup.+
2-(3-Fluoro-4-hydroxy-phenyl)-5-hydroxy-benzofuran-7-carbonitrile
48
[0164] Compound 48 was prepared under the same conditions as 27
yielding 0.052 g (57%) of 48 as a yellow solid: Mp<300.degree.
C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.5 (br s, 1 H), 9.92 (br
s, 1 H), 7.69 (dd, 1 H, J=12.1 Hz, 2.0 Hz), 7.56 (dd, 1 H, J=8.4
Hz, J=1.5), 7.31 (s, 1 H), 7.28 (d, 1 H, J=2.4 Hz), 7.11 (d, 1 H),
J=2.4 Hz), 7.09 (t, 1 H, J=8.8 Hz); MS 268 (M-H).sup.-
2-(3-Fluoro-4-hydroxy-phenyl)-7-methyl-benzofuran-5-ol 49
[0165] Compound 49 was prepared under the same conditions as 9,
yielding 0.018 g (54%) of 49 as a white solid: Mp=196-198.degree.
C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.3 (br s, 1 H), 9.1 (br s,
1 H), 7.64 (dd, 1 H, J=12.5 Hz, 2.0 Hz), 7.52 (dd, 1 H, J=8.4 Hz,
J=1.5 Hz), 7.31 (s, 1 H), 7.05 (t, 1 H, J=8.7 Hz), 6.71 (d, 1 H,
J=2.3 Hz), 6.54 (d, 1 H, J=1.6 Hz); MS 257 (M-H).sup.-
Synthesis of Compounds in Scheme 5
3-Bromo-2-hydroxy-5-methoxy-benzaldehyde 50
[0166] To a cooled 0.degree. C. solution of Methyl
4-methoxysalicylate (30 g, 200 mmol) in chloroform (500 ml) was
added bromine (32 g, 260 mmol) and the reaction was stirred at rt
for 5 hr. The reaction was then washed with 10% sodium sulfite,
dried, concentrated to give a solid. The solid was triturated with
hexane, filtered to give a yellow solid (14g, 35%):
Mp=107-110.degree. C.
3-Bromo-2,5-dimethoxy-benzaldehyde 51
[0167] A solution of 50 (10 g, 43 mmol), Methyl Iodide (7.3 g, 52
mmol), and K.sub.2CO.sub.3 (12 g, 86 mmol) in acetone (200 ml) was
heated to reflux. After 4 hr, the reaction was cooled, poured into
water and-extracted with ether. The ether layer was dried
concentrated and the product was purified by silica gel column
chromatography (10% EtOActHex) to give 51 as a solid (7.0 g, 67%):
Mp=62-64.degree. C; .sup.1H NMR (CDCl.sub.3) .delta. 10.32 (s, 1
H), 7.38 (d, 1 H, J=2.8 Hz), 7.28 (d, 1 H, J=3.2 Hz), 3.93 (s, 3
H), 3.82 (s, 3 H); MS 245/247 (M+H).sup.+
(3-Bromo-2,5-dimethyoxy-phenyl)-methanol 52
[0168] To a cooled (0.degree. C.) solution of 51 (8.0 g, 33 mmol)
in THF (100 ml) was added LiAlH.sub.4 (15 ml of 1.0M in THF)
dropwise. After 15 min, the reaction was quenched with 2N HCl and
the aqueous layer was extracted with EtOAc. The EtOAc layer was
dried concentrated to give a solid (7.5 g, 93%): Mp=65-67.degree.
C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 7.05 (d, 1 H, J=3.0 Hz),
6.98 (d, 1 H, J=2.5 Hz), 5.28 (t, 1 H, J=4.9 Hz), 4.47 (d, 2 H,
J=5.7 Hz); 3.73 (s, 3 H), 3.67 (s, 3 H); MS 245 (M-H).sup.-
1-Bromo-3-chloromethyl-2,5-dimethoxy-benzene 53
[0169] To a solution of 52 (7.5 g, 30 mmol) and ZnCl.sub.2 (1 g) in
THF (100 ml) was added SOCl.sub.2 (5.31 g, 45 mmol) dropwise. After
1 hr at rt, the reaction was poured into water and extracted with
ether. The ether was dried, concentrated and the product was
purified by column chromatography on silica gel (10% EtOAc/hex) to
give 53 as an oil (5.5 g, 75%): .sup.1H NMR(DMSO-d.sub.6) .delta.
7.21(d, 1 H, J=3.0 Hz), 7.08 (d, 1 H, J=3.0 Hz), 4.73 (s, 2 H),
3.78 (s, 3 H), 3.75 (s, 3 H)
(3-Bromo-2,5-dimethoxy-phenyl)-acetonitrile 54
[0170] A solution of 1-Bromo-3-chloromethyl-2,5-dimethoxy-benzene
53 (7.0 g , 26.4 mmol) and KCN (1.7 g, 26.4 mmol) in DMSO (50 ml)
was heated to 75.degree. C. After 2 hr the reaction was cooled and
poured into water. The aqueous layer was extracted with EtOAc and
the organic layer was dried and concentrated. The product was
purified by column chromatography on silica gel (20% EtOac/Hex) to
give 54 as an oil (5.2 g, 77%): .sup.1H NMR (DMSO-d.sub.6) .delta.
7.20 (d, 1 H, J=3.0 Hz), 6.99 (d, 1 H, J=3.0 Hz), 4.00 (s, 2 H),
3.75 (s, 6 H)
(3-Bromo-2,5-dimethoxy-phenyl)-acetic acid 55
[0171] A solution of (3-Bromo-2,5-dimethoxy-phenyl)-acetonitrile 54
(5.2 g, 20.4 mmol) in water (10 ml), conc H.sub.2SO.sub.4 (10 ml),
and AcOH (30 ml) was heated to 100.degree. C. After 3 hr the
reaction was cooled and poured into water. The aqueous layer was
extracted with EtOAc which was then dried over MgSO.sub.4, filtered
and concentrated. The product was purified by column chromatography
on silica gel (50% EtOAc/Hex) to give a solid (2.8 g, 55%):
Mp=62-65.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 12.45 (br
s, 1 H), 7.09 (d, 1 H, J=2.9 Hz), 6.87 (d, 1 H, J=3.0 Hz), 3.72 (s,
3 H), 3.66 (s, 3 H), 3.59 (s, 2 H); MS 273/275 (M-H).sup.-.
2-(3-Bromo-2,5-dimethoxy-phenyl)-1-(4-methoxy-phenyl)-ethoanone
56
[0172] To a cooled (0.degree. C.) solution of 55 (2.8 g, 10 mmol)
in CH.sub.2Cl.sub.2 (50 ml) was added SOCl.sub.2 (1.8 g, 15 mmol)
and DMF (2 ml) and the reaction was stirred for 3 hr. The solution
was concentrated and the resulting oil was taken up into
dichloroethane (50 ml). The solution was cooled and anisole (2.0 g,
18.4 mmol) was added followed by AlCl.sub.3 (1.8 g, 13.8 mmol). The
reaction was stirred for 1 hr and was then quenched with 2N HCl aq.
The organic layer was dried over MgSO.sub.4, concentrated to give
an oil which was taken up into MeOH and a solid crystallized. The
solid was collected by filtration to give a white solid (2.3 g,
63%); Mp=91-93.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 8.01
(d, 2 H, J=8.4 Hz),7.10-7.05 (m, 3 H). 6.85 (d, 1 H, J=5.7 Hz),
4.35 (s, 2 H), 3.85 (s, 3 H), 3.72 (s, 3 H), 3.59 (s,3 H); MS
363/365 (M-H).sup.-
7-Chloro-2-(4-hydroxy-phenyl)-benzofuran-5-ol 57 and
7-Bromo-2-(4-hydroxy-phenyl)-benzofuran-5-ol 58
[0173] A mixture of 57 (0.5 g, 1.35 mmol) and Pyridine HCl (5 g)
was heated to 200.degree. C. After 1 Hr, the reaction was cooled
and then diluted with water. The aqueous phase was extracted with
EtOAc. The EtOAc was dried, concentrated to give a solid which was
purified by reverse phase HPLC to give 57 (5 mg, 1.5%) and 58 (60
mg, 15%).
[0174] 57: Mp=235-237.degree. C.: .sup.1H NMR (DMSO-d.sub.6)
.delta. 9.94 (br s, 1 H), 9.62 (br s, 1 H), 7.72 (d, 2 H, J=8.5
Hz), 7.12 (s, 1 H), 6.91- 6.87 (m, 3 H), 6.74.(d, 1 H, J=5.2 Hz);
MS 259/261 (M-H).sup.-.
[0175] 58: Mp=242-244.degree. C.; .sup.1H NMR(DMSO-d.sub.6) .delta.
9.92 (br s, 1 H), 9.68 (br s, 1 H), 7.69 (d, 2 H, J=8.6 Hz), 7.14
(s, 1 H), 6.90-6.87 (m, 4 H); MS 303/305 (M-H).sup.-.
3-[5-Hydroxy-2-(4-hydroxy-phenyl)benzofuran-7-yl]-acrylic acid
methyl ester 59
[0176] To a solution of
7-bromo-2-(4-hydroxy-phenyl)-benzofuran-5-ol 58 (1.0 g, 3.3 mmol)
in triethylamine (10 mL) and acetonitrile (10 mL) was added methyl
acrylate (0.44 mL, 4.9 mmol) and tri-(o-toly) phosphine (0.2 g,
0.66 mmol). This mixture was purged with nitrogen for 10 minutes.
Then palladium (II) acetate (0.037 g, 0.17 mmol) was added and the
reaction was heated at reflux for 4 hours. To the cooled reaction
was added 2N HCl and the product was extracted into ethyl acetate.
The organic layer was washed with brine, dried over MgSO.sub.4 and
the solvent removed in vacuo. The residue was purified via flash
chromatography on silica gel, eluting with 22-50% eithyl acetate in
hexane to give 0.16 g of 59: Mp=231-234.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.93 (s, 1 H), 9.44 (s, 1 H), 7.80 (d, 1H,
J=16.1 Hz), 7.72 (d, 2 H, J=8.6 Hz), 7.13 (s, 1 H), 7.02 (d, 1 H,
J=2.3 Hz), 6.98 (d, 1 H, J=2.3 Hz), 6.93 (d, 1 H, J=16.2 Hz), 6.92
(d, 2 H J=8.6 Hz) 3.79 (s, 3 H); MS 311 (M+H).sup.+
3-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-propionic acid
methyl ester 60
[0177] To a solution of
3-[5-hydroxy-2-(4-hydroxy-phenyl)benzofuran-7-yl]-acrylic acid
methyl ester 59 (0.1 g, 0.32 mmol) in methanol (5 mL) and purged
with nitrogen was added catalytic 10% palladium on carbon. The
reaction vessel was evacuated and a balloon of hydrogen was added.
After 7 hours, the reaction was filtered and the solvent removed in
vacuo. The product was purified via flash chromatography on silica
gel, eluting with 7% methanol in dichloromethane to give 0.015 g of
3-[5-hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-propionic acid
methyl ester 60: Mp=167-170.degree. C.; .sup.1H NMR (DMSO-d.sub.6)
.delta. 9.83 (s, 1 H), 9.08 (s, 1 H), 7.70 (d, 2 H, J=8.6 Hz), 7.00
(s, 1 H), 6.87 (d, 2 H, J=8.6 Hz), 6.73 (d, 1 H, J=2.3 Hz), 6.53
(d, 1 H, J=2.2 Hz), 3.59 (s, 3 H), 3.07 (t, 2 H, J=8.6 Hz), 2.77
(t, 2 H, J=7.6 Hz); MS 313 (M+H).sup.+.
3-[5-Hydroxy-2-(4-hydroxyphenyl)-benzofuran-7-yl]-acrylamide 61
[0178] To a solution of
7-bromo-2-(4-hydroxy-phenyl)-benzofuran-5-ol 58 (0.3 g, 0.98 mmol)
in triethylamine (5 mL) and acetonitrile (5 mL) was added
acrylamide (0.077 g, 1.08 mmol) and tri-(o-tolyl) phosphine (0.060
g, 0.2 mmol). This mixture was purged with nitrogen for 10 minutes.
Then palladium (II) acetate (0.022 g, 0.098 mmol) was added and the
reaction was heated at reflux for 3.5 hours. To the cooled reaction
was added 2N HCl and the product was extracted into ethyl acetate.
The organic layer was washed with brine, dried over MgSO.sub.4 and
the solvent removed in vacuo. The residue was purified via flash
chromatography on silica gel, eluting with 10% methanol in
dichloromethane to give 0.15 g of
3-[5-hydroxy-2-(4-hydroxyphenyl)-benzofuran-7-yl]-acrylamide 61:
Mp=275.degree. C. (dec); .sup.1H NMR (DMSO-d.sub.6) .delta. 9.89
(s, 1 H), 9.35 (s, 1 H), 7.86 (br s, 1 H), 7.83 (d, 2 H, J=8.6 Hz),
7.53 (d, 1 H, J=15.9 Hz), 7.23 (br s, 1 H), 7.11 (s, 1 H), 7.04 (d,
1 H, J=15.9 Hz), 6.94 (d, 1 H, J=2.4 Hz), 6.90 (d, 2 H, 8.7 Hz);
6.83 (d, 1 H, J=2.3 Hz); MS 296 (M+H).sup.+
2-(4-Hydroxy-phenyl)-7-methoxy-benzofuran-5-ol 62
[0179] A solution consisting of 58 (1.5 g, 4.9 mmol) in DMF (25 mL)
was treated with CuIBr (1.0 g, 6.5 mmol) and NaOMe (6 mL, 4.4 N in
MeOH, 27 mmol) and heated to 160.degree. C. for approximately 1
hour. The reaction mixture was allowed to cool and then worked up
by adding 2 N HCl and EtOAc. The EtOAc layer was washed with
NaHCO.sub.3 aq. brine and dried over MgSO.sub.4. The solution was
concentrated and chromatographed on silica gel (1:4 EtOAc/hexanes
to 3:7 EtOAc/hexanes) to yield 0.47 g of pdt: Mp=167-168.degree.
C., .sup.1H NMR (DMSO-d.sub.6) .delta. 9.84 (br s, 1 H), 9.18 (br
s, 1 H), 7.67 (d, 2 H, J=8.6 Hz), 6.99 (s, 1 H), 6.86 (d, 2 H,
J=8.7 Hz), 6.46 (d, 1 H, J=2.1 Hz), 6.34 (d, 1 H, J=2.1 Hz), 3.89
(s, 3 H); MS 257 (M+H).sup.+.
4,7-Dibromo-2-(4-hydroxy-phenyl)-benzofuran-5-ol 63
[0180] Compound 59 (0.6 g, 2.1 mmol) in CH.sub.3CN was treated with
K.sub.2CO.sub.3 (0.58 g, 4.1 mmol) followed by NBS (0.37 g, 2.1
mmol) and the reaction was stirred at rt for 30 mins and then
treated with a 10% Na.sub.2SO.sub.3 aq solution followed by
NaHCO.sub.3 aq. EtOAc was added and the organic layer was washed
with brine and dried over MgSO4. The material was purified by
reverse phase HPLC using a gradient (Water/CH3CN 80:20 to
Water/CH3CN 20:80) to render 40 mg of the desired pdt as a grey
powder: Mp=215-217.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta.
10.3 (br s, 1 H), 10.1 (br s, 1 H), 7.79 (d, 2 H, J=8.7 Hz), 7.18
(s, 1 H), 7.06 (s, 1 H), 6.90 (d, 2 H, J=8.7 Hz), MS 381/383/385
(M-H).sup.-.
3-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-acrylonitrile
64
[0181] A solution of
3-[5hydroxy-2-(4-hydroxyphenyl)-benzofuran-7-yl]-acrylamide 61
(0.07 g, 0.24 mmol) in DMF (5 mL) and phosphorous oxychloride (0.11
mL) was heated at 65.degree. C. for 2 hours. Then ice was added to
the reaction mixture and the product extracted into ethyl acetate.
The organic layer was dried over MgSO.sub.4 and the solvent removed
in vacuo. The crude product was submitted for reverse phase prep
HPLC. The product was isolated to give 0.007 g of
3-[5-hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl-acrylonitrile 64:
.sup.1H NMR (DMSO-d.sub.6) .delta. 9.90 (s, 1 H), 9.48 (s, 1 H),
7.82 (d, 2 H, J=8.6 Hz), 7.79 (d, 1 H, J=16.7 Hz), 7.13 (s, 1 H),
7.03 (d, 1 H, J=2.3 Hz), 6.92 (d, 1 H, J=2.4 Hz), 6.88 (d, 2 H,
J=8.7 Hz), 6.71 (d, 1 H, J=16.8 Hz); MS 276 (M-H).sup.-.
3-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-propionitrile
65
[0182] A solution of
3-[5-hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-acrylonitrile 64
(0.028 g 0.1 mmol) in methanol (1 mL) was purged with nitrogen and
10% palladium on carbon added. The reaction vessel was evacuated
and a hydrogen balloon added. After an hour, the reaction was
filtered and the solvent removed in vacuo. The product was purified
via flash chromatography, eluting with 3% methanol in
dichloromethane to give 0.007 g of
3-[5-hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-propionitrile
65: .sup.1H NMR (DMSO-d.sub.6) .delta. 9.84 (s, 1 H), 9.17 (s, 1
H), 7.73 (d, 2 H, J=8.6 Hz), 7.02 (s, 1 H), 6.87 (d, 2 H, J=8.6
Hz), 6.79 (d, 1 H, J=2.3 Hz), 6.62 (d, 1 H, J=2.2 Hz), 3.12 (t, 2
H, J=7.1 Hz), 2.96 (t, 2 H, J=7.4 Hz); MS 280 (M+H).sup.+.
Synthesis of Compounds from Scheme 6
7-Bromo-5-(tert-butyl-dimethyl-silanyloxy)-2-[4-(tert-butyl-dimethyl-silan-
yloxy)-phenyl]-benzofuran 66
[0183] To a solution of
7-bromo-2-(4-hydroxy-phenyl)-benzofuran-5-ol 58 (0.5 g, 1.6 mmol)
in THF was added imidazole (0.33 g, 4.8 mmol) and
tert-butyldimethyl silylchloride (0.69 g, 4.6 mmol). This mixture
was stirred at room temperature overnight. The reaction mixture was
diluted with ethyl ether and washed with water, then dried over
MgSO.sub.4 and the solvent removed in vacuo. The crude was purified
via flash chromatography, eluting with hexane, giving 0.62 g of
5-(tert-butyl-dimethyl-silanyloxy)-2-[4-tert-butyl-dimethyl-silanyloxy)-p-
henyl]-7-bromo-benzofuran 66: .sup.1H NMR (DMSO-d.sub.6) .delta.
7.81 (d, 2 H, J=8.6 Hz), 7.29 (s, 1 H), 7.08 (d, 1 H, J=2.2 Hz),
7.02 (d, 2 H, J=8.7 Hz), 7.00 (d, 1 H, J=2.2 Hz), 0.97 (s, 18 H),
0.24 (s, 6 H), 0.23 (s, 6 H).
2-(4-Hydroxy-phenyl)-7-vinyl-benzofuran-5-ol 67
[0184] To a solution of 66 (0.48 g, 0.9 mmol) in xylene was added
tributyl vinyl tin (0.28 g, 0.9 mmol) and tri-(o-tolyl)phosphine
(0.055 g, 0.18 mmol). This mixture was purged with nitrogen for 15
minutes. Then palladium (II) chloride was added and the reaction
was heated at 130.degree. C. for 2 hours. The reaction was filtered
and the solvent removed in vacuo. The residue was used in the next
step without further purification. To a solution of
5-(tert-butyl-dimethyl-silanyloxy)-2-[4-tert-butyl-dimethyl-silanyloxy)-p-
henyl]-7-vinyl-benzofuran (0.4 g, 0.9 mmol) in THF (10 mL) was
added 1.0M tetrabutyl ammonium fluoride (1.8 mL, 1.8 mmol) and the
reaction mixture was stirred at room temperature 20 minutes. The
reaction was diluted with ethyl ether and washed twice with water.
The organic layer was dried over MgSO.sub.4 and the solvent removed
in vacuo. The product was purified via flash chromatography,
eluting with 50% ethyl acetate in hexane, to give 0.19 g of
2-(4-hydroxy-phenyl)-7-vinyl-benzofuran-5-ol 67: Mp=182-184.degree.
C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.86 (s, 1 H), 9.20 (s, 1
H), 7.73 (d, 2 H, J=8.6 HZ), 7.06 (s, 1 H), 6.89 (d, 2 H, J=8.8
Hz), 6.92 (dd, 1 H, J=16.7 Hz, 11.3 Hz), 6.84 (d, 1 H, J=2.3 Hz),
6.76 (d, 1 H, J=2.3 Hz), 6.21 (dd, 1 H, J=17.8 Hz, 1.2 Hz), 5.54
(dd, 1 H, J=11.3 Hz, 1.2 Hz); MS 253 (M+H).sup.+.
2,2,2-Trifluoro-1-[(hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-ethanone
68
[0185] Compound 66 (0.6 g, 1.1 mmol) in 10 mL of THF was cooled to
-78.degree. C. and treated by dropwise addition of n-BuLi (0.6 mL,
2.5 M in hexanes, 1.5 mmol). After stirring for 5 minutes, a
solution containing (N-methoxy,N'-methyl)-acetamide in 1 mL THF was
added and the rxn was allowed to rt and stirred overnight. The
crude reaction mixture was treated with a few mLs of 2 N HCl aq and
the THF evaporated off. The aqueous layer was extracted with EtOAc,
washed with NaHCO.sub.3 aq, brine, and dried over MgSO.sub.4. After
filtration, the EtOAc was concentrated and chromatographed on
silica gel (0:100 EtOAc/hexanes to 1:4 EtOAc/hexanes). The
concentrated fractions containing the silylated phenols were
concentrated and redissolved in 5 mLs of THF and treated with
tetrabutyl ammonium fluoride (TBAF) (2 mL, 1 M in THF). After
stirring for 30 minutes, the reaction mixture was acidified with 2
N HCl aq, the THF was evaporated off and the aqueous layer
extracted with EtOAc. The EtOAc layer was washed with saturated
NaHCO.sub.3 aq, brine and dried over MgSO.sub.4. After filtration,
the EtOAc was concentrated and chromatographed on silica gel (5:95
EtOAc/hexanes to 4:6 EtOAc/hexanes) to yield 80 mg of the desired
pdt as an orange solid: Mp=215-216.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.84 (br s, 1 H), 9.22 (br s, 1 H), 7.68 (d,
2 H, J=8.5 Hz), 7.00 (s,1 H), 6.98 (d, 1 H, J=2.5 Hz), 6.92 (d, 1
H, J=2.5 Hz), 6.88 (d, 2 H, J=8.6 Hz); MS 321 (M-H).sup.-.
4-Chloro-2-(4-hydroxy-phenyl)-7-methoxy-benzofuran-5-ol 69
[0186] Compound 62 (0.1 g, 0.39 mmol) in CH.sub.3CN (10 mL) was
treated with portionwise addition of NCS (0.033 g, 0.24 mmol).
After addition, 10% Na.sub.2SO.sub.3 aq was added followed by
NaHCO.sub.3 and brine. The EtOAc layer was dried over MgSO4,
filtered, concentrated and chromatographed on silica gel (3:7
EtOAc/hexanes) to yield 0.016 g of the product: Mp=176-177.degree.
C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.89 (br s, 2 H), 7.74 (d, 2
H, J=8.6 Hz), 7.10 (s, 1 H), 6.87 (d, 2 H, J=8.7 Hz), 6.55 (s, 1
H), 3.91 (s, 3 H); MS 291 (M+H).sup.+.
4-Bromo-2-(4-hydroxy-phenyl)-7-methoxy-benzofuran-5-ol 70
[0187] Compound was prepared analogously to chloro-analogue 69
except that NBS was used as the halogenating agent: Mp=170.degree.
C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.91 (br s, 2 H), 7.74 (d, 2
H, J=8.6 Hz), 7.01 (s, 1 H), 6.86 (d, 2 H, J=8.7 Hz), 6.56 (s, 1
H), 3.91 (s, 3 H); MS 333 (M-H).sup.-.
5-Hydroxy-2-(4-hydroxy-phenyl)-7-methoxy-benzofuran-4-carbaldehyde
71
[0188] A solution of 62 (0.25 g, 1.0 mmol) in DMF (20 mL) was
treated with POCl.sub.3 (1 mL, 11 mmol) and heated at 80.degree.
C.-100.degree. C. for 15 minutes. The reaction mixture was worked
up by allowing to cool and then poured into crushed ice. 2N NaOH aq
was added and the solution stirred for several minutes and then the
mixture was acidified with 2N HCl aq and then neutralized with
NaHCO.sub.3 aq. The mixture was then extracted with EtOAc and
washed with brine, dried over MgSO.sub.4, filtered, concentrated
and chromatographed on silica gel (2:8 to 4:6 EtOAc/hexanes) to
yield a solid which still contained some starting material, but
that was purified by trituration with EtOAc to yield 47 mg the
desired pdt as a white solid: Mp=254-255.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 10.29 (s, 1 H), 10.0 (br s, 1 H), 7.73 (d, 2
H, J=8.7 Hz), 7.59 (s, 1 H), 6.88 (d, 2 H, J=8.7 Hz), 6.46 (s, 1
H), 4.00 (s, 3 H); MS 281 (M-H).sup.-.
5-Hydroxy-2-(4-hydroxy-phenyl)-7-methoxy-benzofuran-4-carbaldehyde
oxime 72
[0189] Compound 71 (0.029 g, 0.1 mmol) in EtOH/Pyr (1 mL/0.5 mL)
was treated with NH.sub.2OH HCl (0.040 g, 0.58 mmol) and the
mixture heated briefly to reflux (approximately 5 minutes) and
allowed to cool and then the solution was partitioned between EtOAc
and 2 N HCl aq and the organic layer was then washed with
NaHCO.sub.3 aq, brine, dried over MgSO.sub.4, filtered,
concentrated and triturated with CH.sub.2Cl.sub.2 to render 29 mg
of the desired oxime: Mp=205.degree. C. (dec.): .sup.1H NMR
(DMSO-d.sub.6) .delta. 11.1 (s, 1 H), 10.0 (s, 1 H), 9.90 (s, 1 H),
8.53 (s, 1 H), 7.65 (d, 2 H), J=8.6 Hz), 7.39 (s, 1 H), 6.88 (d, 2
H, J=8.7 Hz), 6.47 (s, 1 H), 3.94 (s, 3 H); MS 300 (M+H).sup.+.
5-Hydroxy-2-(4-hydroxy-phenyl)-7-methoxy-benzofuran-4-carbonitrile
73
[0190] Compound 62 (0.49 g, 1.9 mmol) in 20 mL of DMF was treated
with 1 mL of POCl.sub.2 and heated at 80.degree. C.-100.degree. C.
for 1 hour, coded and treated with a few mLs of 2 N NaOHaq. After
stirring for a few minutes, the reaction mixture was then acidified
with excess 2N HCl aq and the entire reaction mixture was then
extracted with EtOAc, washed with NaHCO.sub.3, brine and dried over
MgSO.sub.4. Filtration and concentration yielded the crude 4-formyl
derivative (0.25 g) that was used as is for the next step.
[0191] Compound 71 (0.25 g, 0.88 mmol), in a solution consisting of
5 mL pyr/5 mL EtOH and treated with NH.sub.2OH--HCl (0.2 g, 2.9
mmol) and the reaction mixture was heated briefly to boiling and
then allowed to cool. The solution was concentrated and the residue
was dissolved in EtOAc and washed with 2N HCl aq and then
NaHCO.sub.3 aq followed by brine. The solution was then dried over
MgSO.sub.4, filtered and concentrated to render the crude
oxime.
[0192] The crude 7 oxime 72 was heated in neat Ac.sub.2O at
100.degree. C. for 30 minutes. The Ac.sub.2O was removed and the
crude product was dissolved in EtOAc, washed with brine and dried
over MgSO.sub.4. The solution was concentrated down and the crude
triacetate was dissolved in DMF (10 mL) and treated with NaH (0.1
g, 60% dispersion in mineral oil, 2. 5 mmol) and the reaction
mixture was heated to 100.degree. C. for 15 min. After cooling to
rt, the solution was treated with a 20% NaOH aq solution and enough
MeOH to get everything in one phase. This solution was then heated
briefly (long enough to hydrolyze the acetates as determined by TLC
analysis) and allowed to cool back to rt. The solution was acidifed
with 2N HCl aq and the solution was extracted with EtOAc. The EtOAc
extract was washed with NaHCO.sub.3 and brine and dried over
MgSO.sub.4. The solution was filtered, concentrated and
chromatographed on silica gel (2:8 to 4:6 EtOAc/hexanes) to yield
80 mg of the pdt nitrile 73 as a white solid: Mp=286-288.degree.
C.;
[0193] .sup.1H NMR (DMSO-d.sub.6) .delta. 10.9 (br s, 1 H), 9.98
(br s, 1 H), 7.77 (d, 2 H, J=8.7 Hz), 7.20 (s, 1 H), 6.87 (d, 2 H,
J=8.7 Hz), 6.48 (s, 1 H), 3.97 (s, 3 H).
2-(3-Fluoro-4-hydroxy-phenyl)-5-hydroxy-7-methoxy-benzofuran-4-carbonitril-
e 73a
[0194] Compound 73a was prepared analogously to compound 73:
Mp=265-267.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 11.0-10.3
(br s, 2 H), 7.75 (d, 1 H, J=12.2 Hz, 2.0 Hz), 7.59 (dd, 1 H, J=8.4
Hz, 1.4 Hz), 7.34 (s, 1 H), 7.06 (t, 1 H, J=8.78 Hz), 6.51 (s, 1
H), 3.98 (s, 3 H); MS 300 (M+H).sup.+
Synthesis of Compounds from Scheme 7
2-(2,5-Dimethoxy-phenyl)-1-(4-methoxy-phenyl)-ethanone 74
[0195] To a cooled solution (0.degree. C.) of anisole (1.3 g, 12.4
mmol) and (2,5-Dimethoxyphenyl)acetyl chloride (2.2 g, 10.3 mmol)
in dichloroethane (30 ml) was added AlCl.sub.3 (1.6 g, 12.4 mmol)
and the reaction was stirred for thirty minutes. The reaction was
then quenched with 2N HCl and the organic layer was then separated,
dried, and concentrated. The resulting oil was taken up into MeOH
and a solid crystallized which was collected by filtration to give
a white solid (1.7 g, 58%): Mp=108-111.degree. C.; .sup.1H NMR
(CDCl.sub.3) .delta. 8.01 (d, 2 H, J=9.0 Hz), 6.92 (d, 2 H, J=8.8
Hz), 6.80-6.70 (m, 3 H), 4.20 (s, 2 H), 3.86 (s, 3 H), 3.75 (s, 3
H), 3.74 (s, 3 H); MS 287 (M+H).sup.+
2-(4-Hydroxy-phenyl)-benzofuran-5-ol 75
[0196] A mixture of 74 (1.5 g, 5.2 mmol) and Pyridine HCl (10 g)
was heated to 200.degree. C. After 1.5 hr. the reaction was cooled
and diluted with water. The aqueous layer was extracted with EtOAc
and the organic layer was dried, concentrated to give a solid which
was triturated with CH.sub.2Cl.sub.2 to give a solid (0.6 g, 51%):
Mp=275-278.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.81 (br
s, 1 H), 9.12 (br s, 1 H), 7.66 (d, 2 H, J=2.5 Hz), 7.32 (d, 1 H,
J=8.5 Hz), 7.00 (s, 1 H), 6.90-6.83 (m, 3 H), 6.65 (dd, 1 H, J=8.6
Hz, 2.6 Hz); MS 225 (M-H).sup.-.
2-(2,5-Dimethoxy-phenyl)-1-(2-fluoro-4-methoxy-phenyl)-ethanone 76
and 2-(2-Fluoro-4-hydroxy-phenyl)-benzofuran-5-ol 77
[0197] A solution of 3-Fluoro anisole (2 g, 16 mmol) and
2,5-dimethoxyphenacetyl chloride in dichloroethane (50 mL) was
treated with AlCl.sub.3 (2.3 g, 18 mmol) and stirred at rt until
TLC analysis indicated reaction was complete. The reaction was
worked up by adding a 2 N HCl aq solution to the reaction (slowly)
and washing with saturated NaHCO.sub.3 aq, brine and drying over
MgSO.sub.4. After filtering, the EtOAc was concentrated and
chromatographed on silica gel (EtOAc/hexanes 1:4) to yield 1 gram
of the acylated intermediate 76 as well as an isomer as an oily
solid that was used as is for the next reaction step. All of 76
from the previous step (1 G, 3.3 mmol) was heated with pyr-HCl at
180-200.degree. C. until TLC indicated reaction completion. The
reaction was worked up by partitioning between 2 N HCl aq and EtOAc
and washing the EtOAc with saturated NaHCO.sub.3, brine, and drying
over MgSO.sub.4. The solution was filtered, concentrated and
chromatographed on silica gel to yield 0.48 g of impure pdt 77. The
product thus obtained was recrystallized from EtOAc/hexanes to
yield desired product plus a small amt of unidentified impurity.
Mp=218-222.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.39 (s,
1 H), 9.20 (s, 1 H), 7.74 (t, 1 H, J=8.7 Hz), 7.37 (d, 1 H, J=8.8
Hz), 6.96-6.94 (m, 2 H), 6.79-6.70 (m, 3 H); MS 243
(M-H).sup.-.
5-OMe-Benzofuran 2-boronic acid 78
[0198] A solution of 5-OMe benzofuran (10 g, 67.6 mmol) in THF (150
mL) was cooled to -78.degree. C. and treated by dropwise addition
of n-BuLi (30 mL, 75 mmol, 2.5 M in hexanes) and stirred at
-78.degree. C. for 5-10 minutes. Trimethyl borate (60 mL, 0.54 mol)
was added quickly and the reaction was allowed to come to rt. The
solution was then treated with 2 N HCl aq and the THF was
evaporated off. The product precipitated out and was collected by
filtration to render 11 g of the desired material as a solid that
was used as is for the subsequent reaction.
4-(5-Methoxy-benzofuran-2-yl)-3-methyl-phenol 79
[0199] A solution of 78 (1 g, 5.4 mmol) and 3-methyl-4-bromo phenol
(0.8 g, 7.0 mmol) in EtOH/toleune/2M Na.sub.2CO.sub.3 aq (1/5/5
ratio) was treated with Pd(PPh.sub.3).sub.4 (0.3 g, 0.27 mmol), and
heated at reflux and monitored by TLC for reaction completion. The
reaction was worked up by partitioning between EtOAc/2 N HCl aq,
washing the EtOAc layer with saturated NaHCO.sub.3 aq, brine and
drying over MgSO.sub.4. After filtering, the solution was
concentrated and chromatographed on silica gel (EtOAc/hexanes 1:9)
to yield 0.32 g of the desired product: Mp=149-154.degree. C.;
.sup.1H NMR (DMSO-d.sub.6) .delta. 9.76 (br s, 1 H), 7.62 (d, 1 H,
J=9.2 Hz), 7.61 (d, 1 H, J=1.7 Hz), 7.14 (d, 1 H, J=2.6 Hz), 6.90
(s, 1 H), 6.86 (dd, 1 H, J=8.9 Hz, 2.6 Hz), 6.75-6.72 (m, 2 H
(protons overlapping)), 3.79 (s, 3 H), 2.45 (s, 3 H); MS 253
(M-H).sup.-.
2-(4-Hydroxy-2-methyl-phenyl)-benzofuran-5-ol 80
[0200] A mixture of the monomethyl ether 79 (0.27 g, 1.1 mmol) and
Pyr-HCl was heated at 180.degree. C. for 30-45 minutes. The
reaction mixture was allowed to cool and partitioned between EtOAc
and 2 N HCl aq and the EtOAc was washed with brine and dried over
MgSO.sub.4. The solution was filtered, concentrated and
chromatographed on silica gel (EtOAc/hexanes 1:3):
Mp=167-169.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 8.61 (s,
1 H), 8.11 (s, 1 H), 7.67 (d, 1 H, J=8.9 Hz), 7.33 (d, 1 H), J=8.7
Hz), 7.02 (d, 1 H, J=2.4 Hz), 6.82-6.78 (m, 4 H (overlapping
protons)), 2.50 (s, 3 H); MS 239 (M-H).sup.-.
5-Bromo-2-(4-methoxy-phenyl)-benzofuran 81
[0201] A solution of 4-Bromo-2-Iodophenol [207115-22-8] (0.9 g, 3.0
mmol), 4-Methoxyphenylacetylene (0.43 g, 3.3 mmol),
PdCl.sub.2P(PH.sub.3).sub.2 (70 mg), and CuI (50 mg) in
DMF/Diethylamine (10 ml) was heated to 60.degree. C. After 1 hr,
the reaction was cooled and poured into water which was extracted
with EtOAc. The organic layer was dried over MgSO.sub.4 and
concentrated to give a solid which was triturated with MeOH,
filtered to give a solid (0.4 g, 45%): Mp=192-194.degree. C.;
.sup.1H NMR (CDCl.sub.3) .delta. 7.77 (d, 2 H, J=9.1 Hz), 7.66 (s,
1 H), 7.37-7.32 (m, 2 H), 6.98 (d, 2 H, J=9.1 Hz), 6.82 (d, 1 H,
J=0.8 Hz), 3.87 (s, 3 H).
5-Chloro-2-(4-methoxy-phenyl)-benzofuran 82
[0202] A solution of 4-Chloro-2-Iodophenol [71643-66-8] (1.0 g, 3.9
mmol), 4-Methoxyphenylacetylene (0.53 g, 4.0 mmol),
PdCl.sub.2P(PH.sub.3).sub.2 (70 mg), and CuI (50 mg) in
DMF/Diethylamine (10 ml) was heated to 60.degree. C. After 1 hr,
the reaction was cooled and poured into water which was extracted
with EtOAc. The organic layer was dried, concentrated to give a
solid which was triturated with MeOH, filtered to give a solid (0.5
g, 50%): Mp=183-185.degree. C.; .sup.1H NMR (CDCl.sub.3) .delta.
7.76 (d, 2 H, J=8.0 Hz), 7.50 (d, 1 H, J=1.6 Hz), 7.39 (d, 1 H,
J=8.3 Hz), 7.20-7.18 (m, 1 H), 6.97 (d, 2 H, J=8.3 Hz), 6.82 (s, 1
H), 3.86 (s, 3 H).
5-Fluoro-2-(4-methoxy-phenyl)-benzofuran 83
[0203] A solution of 4-Fluoro-2-Iodophenol [2713-29-3] (0.9 g, 3.8
mmol), 4-Methoxyphenylacetylene (0.53 g, 4.0 mmol),
PdCl.sub.2P(PH.sub.3).sub.2 (70 mg), and CuI (50 mg) in
DMF/Diethylamine (10 ml) was heated to 60.degree. C. After 1 hr,
the reaction was cooled and poured into water which was extracted
with EtOAc. The organic layer was dried over MgSO.sub.4, filtered
and concentrated to give a solid which was triturated with MeOH,
and filtered to give 83 as a solid.
5-tert-Butyl-2-(4-methoxy-phenyl)-benzofuran 84
[0204] A solution of 4-t-butyl-2-iodophenol [38941-98-9] (1.0 g,
3.6 mmol), 4-Methoxyphenylacetylene (0.53 g, 4.0 mmol),
PdCl.sub.2P(PH.sub.3).sub.2 (70 mg), and CuI (50 mg) in
DMF/Diethylamine (10 ml) was heated to 60.degree. C. After 1 hr,
the reaction was cooled and poured into water which was extracted
with EtOAc. The organic layer was dried, concentrated to give a
solid which was triturated with MeOH, filtered to give 84 as a
solid.
5,7-Dichloro-2-(4-methoxy-phenyl)-benzofuran 85
[0205] A solution of 2,4-Dichloro-6-iodo-phenol [2040-83-7] (2.0 g,
6.9 mmol), 4-Methoxyphenylacetylene (0.91 g, 6.9 mmol),
PdCl.sub.2P(PH.sub.3).sub.2 (0.15 g), and CuI (50 mg) in
DMF/Diethylamine (20 ml) was heated to 60.degree. C. After 1 hr,
the reaction was cooled and poured into water which was extracted
with EtOAc. The organic layer was dried over MgSO.sub.4, filtered
and concentrated to give a solid which was triturated with MeOH,
filtered to give 85 as a solid (0.80 g, 42%): Mp=172-174.degree.
C.; .sup.1H NMR (CDCl.sub.3), 7.82 (d, 2 H, J=8.1 Hz), 7.41 (d, 1
H, J=1.8 Hz), 7.24 (d, 1 H, J=1.9 Hz), 7.00 (d, 2 H, J=8.8 Hz),
6.84 (s, 3 H), 3.87 (s, 3 H); MS 293/295 [M+H].sup.+
5,7-Difluoro-2-(4-methoxy-phenyl)-benzofuran 86
[0206] A solution of 2,4-Difluoro-6-iodo-phenol (1.0 g, 3.9 mmol),
4-Methoxyphenylacetylene (0.53 g, 4.0 mmol),
PdCl.sub.2P(PH.sub.3).sub.2 (70 mg), and CuI (50 mg) in
DMF/Diethylamine (10 ml) was heated to 60.degree. C. After 1 hr,
the reaction was cooled and poured into water which was extracted
with EtOAc. The organic layer was dried over MgSO.sub.4, filtered
and concentrated to give a solid which was triturated with MeOH and
filtered to give 86 as a solid.
5,7-Dibromo-2-(4-methoxy-phenyl)benzofuran 87
[0207] A solution of 2,4-Dibromo-4-iodo-phenol [53872-06-3] (0.7 g,
1.8 mmol), 4-Methoxyphenylacetylene (0.53 g, 4.0 mmol),
PdCl.sub.2P(PH.sub.3).sub.2 (70 mg), and CuI (50 mg) in
DMF/Diethylamine (10 ml) was heated to 60.degree. C. After 1 hr,
the reaction was cooled and poured into water which was extracted
with EtOAc. The organic layer was dried over MgSO4, filtered and
concentrated to give a solid which was triturated with MeOH and
filtered to give 87 as a solid.
2-(4-Methoxy-phenyl)-5-trifluoromethyl-benzofuran 88
[0208] A solution of 4-Trifluoro-2-iodo-phenol (0.5 g, 1.7 mmol),
4-Methoxyphenylacetylene (0.26 g, 2.0 mmol),
PdCl.sub.2P(PH.sub.3).sub.2 (70 mg), and CuI (50 mg) in
DMF/Diethylamine (10 ml) was heated to 60.degree. C. After 1 hr,
the reaction was cooled and poured into water which was extracted
with EtOAc. The organic layer was dried, concentrated to give a
solid which was triturated with MeOH and filtered to give 88 as a
solid.
4-(5-Bromo-benzofuran-2-yl)-phenol 89
[0209] A mixture of 81 (0.3 g, 1 mmol) and Pyridine HCl (5 g) was
heated to 200.degree. C. After 1 hr, the reaction was cooled and
then diluted with water. The aqueous layer was extracted with
EtOAc, dried over MgSO.sub.4 and concentrated to give a solid. The
solid was triturated with CH.sub.2Cl.sub.2 and filtered to give a
solid (0.11 g, 39%); Mp=228-229.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.95 (br s, 1 H), 7.79 (d, 1 H, J=2.0 Hz),
7.74 (d, 2 H, J=8.8 Hz), 7.55 (d, 1 H, J=8.8 Hz), 7.39 (dd, 1 H,
J=8.8 Hz, 2.4 Hz), 7.16 (s, 1 H), 6.88 (d, 2 H, J=8.8 Hz); MS
287/289 [M-H].sup.-
4-(5-Chloro-benzofuran-2-yl)-phenol 90
[0210] A mixture of 82 (0.5 g, 1.9 mmol) and Pyridine HCl (10 g)
was heated to 200.degree. C. After 1 hr, the reaction was cooled
and then diluted with water. The aqueous layer was extracted with
EtOAc, dried over MgSO.sub.4 and concentrated to give a solid. The
solid was triturated with CH.sub.2Cl.sub.2 and filtered to give a
solid (0.20 g, 47%); Mp=216-218.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.95 (br s, 1 H), 7.74 (d, 2 H, J=8.8 Hz),
7.66 (d, 1 H, J=1.9 Hz), 7.59 (d, 1 H, J=8.8 Hz), 7.27 (dd, 1 H,
J=8.8 Hz, 2.4 Hz), 7.17 (s, 1 H), 6.88 (d, 2 H, J=8.7 Hz); MS
243/245 [M-H].sup.-
4-(5-Fluoro-benzofuran-2-yl)-phenol 91
[0211] Compound 83 was treated with Pyridine HCl (5 g) and heated
to 200.degree. C. After 1 hr, the reaction was cooled and diluted
with water. The aqueous layer was extracted with EtOAc, dried over
MgSO.sub.4, filtered and concentrated to give a solid (0.11 g,
13%); Mp=202-204.degree. C.; .sup.1NMR (DMSO-d.sub.6) .delta. 9.92
(br s, 1 H), 7.73 (d, 2 H, J=8.7 Hz), 7.58 (dd, 1 H, J=8.7 Hz, 4.4
Hz), 7.39 (dd, 1 H, J=8.8 Hz, 2.5 Hz), 7.17 (d, 1 H, J=1.0 Hz),
7.10-7.06 (m, 1 H), 6.88 (d, 2 H, J=8.8 Hz); MS 227 [M+H].sup.+
4-(5-tert-Butyl-benzofuran-2-yl)-phenol 92
[0212] Compound 84 was treated with Pyridine HCl (5 G) and heated
to 200.degree. C. After 1 hr, the reaction was tooled and diluted
with water. The aqueous layer was extracted with EtOAc, dried over
MgSO.sub.4, filtered and the crude product was purified by column
chromatography (eluant 25% EtOAc/hexanes) to give a solid (0.18 g,
17%); Mp=172-174.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta.
9.83 (s, 1H), 7.70 (d, 2 H, J=8.9 Hz), 7.56 (d, 1 H, J=1.7 Hz),
7.45 (d, 1 H, J=9.0 Hz), 7.32 (dd, 1 H, J=9.0 Hz, 2.1 Hz), 7.11 (s,
1 H), 6.87 (d, 2 H, J=8.5 Hz); MS 265 [M-H].sup.-
4-(5,7-Dichloro-benzofuran-2-yl)-phenol 93
[0213] A mixture of 85 (0.7 g, 2.4 mmol) and Pyridine HCl (10 g)
was heated to 200.degree. C. After 1 Hr, the reaction was cooled
and diluted with water. The aqueous layer was extracted with EtOAc,
dried and concentrated to give a solid which was triturated with
MeOH, filtered to give a solid (0.5 g, 75%): Mp=184-186.degree. C;
.sup.1H NMR (DMSO-d.sub.6) .delta. 10.04 (s, 1 H), 7.77 (d, 2 H,
J=8.3 Hz), 7.67 (t, 1 H, J=0.8 Hz), 7.48-7.46 (m, 1 H), 7.26 (s, 1
H), 6.90 (d, 2 H, J=8.2 Hz); MS 277/279 [M-H].sup.-
4-(5,7-Difluoro-benzofuran-2-yl)-phenol 94
[0214] Compound 86 was treated with Pyridine HCl (5 g) and heated
to 200.degree. C. After 1 hr, the reaction was cooled and diluted
with water. The aqueous layer was extracted with EtOAc, dried, and
the product was purified by column chromatography (eluent 25%
EtOAc/hex) to give a solid (0.12 g, 13%): Mp=152-154.degree. C.;
.sup.1H NMR (DMSO-d.sub.6) .delta. 10.01 (br s, 1 H), 7.77 (d, 2 H,
J=8.9 Hz), 7.32-7.25 (m, 3 H), 6.91 (d, 2 H, J=8.9 Hz); MS 245
[M-H].sup.-
4-(5,7-Dibromo-benzofuran-2-yl)-phenol 95
[0215] Compound 87 was treated with Pyridine HCl (5 g) and heated
to 200.degree. C. After 1 hr, the reaction was cooled and diluted
with water. The aqueous layer was extracted with EtOAc, dried over
MgSO.sub.4, and the product was purified by column chromatography
(eluant 25% EtOAc/hexanes) to give a solid (0.12 g, 18%);
Mp=203-205.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.04 (br
s, 1 H), 7.83 (d, 1 H, J=1.5 Hz), 7.75 (d, 2 H, J=8.3 Hz), 7.68 (d,
1 H, J=2.0 Hz), 7.28 (s, 1 H), 6.91 (d, 2 H, J=8.3 Hz); MS
365/367/369 [M-H].sup.-
4-(5-Trifluoromethyl-benzofuran-2-yl)-phenol 96
[0216] Compound 88 was treated with Pyridine HCl (5 g) and heated
to 200.degree. C. After 1 hr, the reaction was cooled and diluted
with water. The aqueous layer was extracted with EtOAc, dried over
MgSO4, and the product was purified by column chromatography
(eluant 25% EtOAc/hexanes) to give the product as a solid: (0.025
g, 4.8%); MS 277 (M-H].sup.-
Synthesis of Compounds from Scheme 8
2-Iodo-4-methoxy-6-nitro-phenol 97
[0217] A solution of 4-Methoxy-2-nitrophenol (5 g, 29.6 mmol) in
MeOH (100 mL) was cooled to 0.degree. C. and treated with KOH (1.8
g, 32.6 mmol) followed by portionwise addition of 12 (8.2 g, 32.6
mmol). The reaction was worked-up by quenching the excess 12 by
adding a 10% Na.sub.2SO.sub.3 aq solution. The MeOH was stripped
off and 2 N HCl aq. was added and the aqueous extracted with EtOAc.
The EtOAc was washed with saturated NaHCO.sub.3, brine and dried
over MgSO.sub.4. The solution was concentrated and triturated twice
with MeOH to yield 5 g of material that consisted of a 2:1 mixture
of product to starting material that was used as is for the next
step.
5-Methoxy-2-4-methoxy-phenyl)-7-nitro-benzofuran 98
[0218] The 2-Iodo-4-methoxy-6-nitro-phenol 97 (1 g, 2.25 mmol based
on 0.67 molar purity) in DMF/pyrrolidine (3 mL/3 mL) was treated
with 4-methoxystyryne (0.45 g, 3.4 mmol), catalytic
PdCl.sub.2(PPh.sub.3).sub.2 and catalytic CuI was heated at
60.degree. C. until reaction was adjudged complete by TLC analysis
(<1 h to completion). The reaction was worked up by portioning
between EtOAc and 2 N HCl aq. The EtOAc was washed with saturated
NaHCO.sub.3 aq, brine and dried over MgSO4. After filtering and
concentrating, the product was purified by trituration with MeOH to
give 0.57 g: Mp 141.degree. C.
2-(4-Hydroxy-phenyl)-7-nitro-benzofuran-5-ol 99
[0219] A mixture of 98 (0.56 g) and Pyr-HCl and heated at
200.degree. C. for 1 h (while occasionally adding more Pyr-HCl).
The reaction was allowed to cool and then partitioned between 2 N
HCl aq and EtOAc. A small amount of MeOH was added to facilitate
the dissolution process. The organic layer was washed with
saturated NaHCO.sub.3 aq, brine, and dried over MgSO.sub.4.
Filtration, concentration and trifuration of the pdt with
CH.sub.2Cl.sub.2 yeilded 0.44 g of the desired pdt which contained
some inorganic impurities. The material was then chromatographed on
silica gel (MeOH/CH.sub.2Cl.sub.2 1:19 to MeOH/CH.sub.2Cl.sub.2
1:9) to yield 0.24 g of 99: Mp=236-237.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 10.06 (br s, 1 H), 7.73 (d, 2 H, J=8.3 Hz),
7.46 (dd, 1 H, J=2.4 Hz, 0.7 HZ), 7.38 (dd, 1 H, J=2.3 Hz, 0.7 Hz),
7.28 (s, 1 H), 6.93 (d, 2 H, J=8.3 Hz); MS 270 (M-H).sup.-.
7-Amino-2-(4-hydroxy-phenyl)-benzofuran-5-ol 100
[0220] A solution of 99 (0.070 g, 0.29 mmol) in AcOH/MeOH was
stirred under an atmosphere of H.sub.2 in the presence of 10% Pd/C.
After TLC analysis indicated reaction was over, the reaction was
filtered through Celite, concentrated and chromatographed on silica
gel (MeOH/CH.sub.2Cl.sub.2 1:9) to yield 25 mg of the desired
product: Mp=251-254.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta.
9.76 (br s, 1 H), 8.65 (br s, 1 H), 7.71 (d, 2 H, J=8.5 Hz), 6.86
(s, 1 H), 6.84 (d, 2 H, J=8.7 Hz), 6.09 (d, 1 H, J=1.9 Hz), 6.02
(d, 1 H, J=1.9 Hz), 5.21 (s, 2 H); MS 242 (M+H).sup.+.
1-(2-Bromo-4-methoxy-phenyl)-2-(2,5-dimethoxy-phenyl)-ethanone
101
[0221] 3-Br Anisole (5 g, 27 mmol) and 2,5-dimethoxy phenacetyl
chloride (6.8 g, 32.4 mmol) in dichloroethane (0.2 L) was cooled to
0.degree. C. and treated with AlCl.sub.3 (4.3 g, 32 mmol). The
reaction was allowed to warm to rt and then worked up by carefully
adding 2 N HCl aq and partitioning the reaction mixture. The
organic layer was washed with NaHCO.sub.3 aq, brine and dried over
MgSO.sub.4. After filtering and concentrating, the residue was
chromatographed on silica gel (1:19 EtOAc/hexanes) to yield the
desired pdt (1.45 g) as the second reaction product to elute from
the column: Mp=76-79.degree. C.
2-(2-Bromo-4-hydroxy-phenyl)-benzofuran-5-ol 102
[0222] Compound 101 (1.25 g, 3.4 mmol) was heated at 200.degree. C.
with a large excess of Pyr-HCl and followed by TLC for reaction
completion (approx 30 min to 1 h). The reaction mixture was allowed
to cool to rt and then partitioned between 2 N HCl aq and EtOAc.
The organic layer was washed with saturated NaHCO.sub.3 aq, brine,
and then dried over MgSO.sub.4. After filtering, the reaction
mixture was concentrated and chromatographed on silica gel (1:1
EtOAc/hexanes) to yield 0.96 g of the desired pdt: Mp=195.degree.
C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.23 (br s, 1 H), 9.23 (br
s, 1 H), 7.70 (d, 1 H, J=8.6 Hz); 7.37 (d, 1 H, J=8.8 Hz), 7.21 (s,
1 H), 7.16 (d, 1 H, J=2.4 Hz), 6.97 (d, 1 H, J=2.4 Hz), 6.92 (dd, 1
H, J=8.7 Hz, 2.4 Hz), 6.75 (dd, 1 H, J=8.8 Hz, 2.4 Hz); MS 303
(M-H).sup.-.
2-(5-Hydroxy-biphenyl-2-yl)-benzofuran-5-ol 103
[0223] Compound 102 (0.2 g, 0.69 mmol) in a solution consisting of
Tol/EtOH/2M Na.sub.2CO.sub.3 aq (5/1/5) was treated with
phenylboronic acid (0.12 g, 1.0 mmol) and cat Pd(PPh.sub.3).sub.4
and heated to reflux until TLC analysis indicated complete
reaction. The reaction was worked up by acidifying with 2 N HCl aq
and extracting with EtOAc. The organic layer was washed with
saturated NaHCO.sub.3 aq, brine, and dried over MgSO.sub.4. After
filtering and concentrating, the crude material was chromatographed
on silica gel (1:9 EtOAc/hexanes to 4:6 EtOAc/hexanes) and then
triturated with hexanes to yield 0.10 g of the desired material:
Mp=167-170.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.98 (br
s, 1 H), 9.07 (br s, 1 H), 7.68 (d, 1 H, J=8.5 Hz), 7.4-7.38 (m, 3
H), 7.26-7.22 (m, 2 H), 7.18 (d, 1 H, J=8.7 Hz), 6.90 (dd, 1 H,
J=8.5 Hz, 2.5 Hz), 6.72 (d, 1 H, J=2.5 Hz), 6.67 (d, 1 H, J=2.3
Hz), 6.62 (dd, 1 H, J=8.7 Hz, 2.4 Hz), 5.81 (s, 1 H).
2-(4'-Benzyloxy-5-hydroxy-biphenyl-2-yl)-benzofuran-5-ol 104
[0224] Compound 102 (0.23 g, 7.9 mmol) in a solution consisting of
Tol/EtOH/2M Na.sub.2CO.sub.3 aq (15 mL/2 mL/15 mL) was treated with
4-benzloxy phenylboronic acid (0.12 g, 1.0 mmol) and cat
Pd(PPh.sub.3).sub.4 and heated to reflux until TLC analysis
indicated complete reaction. The reaction mixture was treated with
2 N HCl aq and extracted with EtOAc. The EtOAc layer was washed
with saturated NaHCO.sub.3 aq, brine and dried over MgSO.sub.4.
After filtration, the residue was chromatographed on silica gel
(1:4 EtOAc/hexanes) to yield the desired product as an orange
solid. The orange solid thus obtained was triturated with
CH.sub.2Cl.sub.2 to yield the pdt (2.4 g) as a white solid: Mp
186-187.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.90 (br s,
1 H), 9.05 (br s, 1 H), 7.65 (d, 1 H, J=8.5 Hz), 7.51-7.31 (m, 5
H), 7.19 (d, 1 H, J=8.5 Hz), 7.17 (d, 2 H, J=8.6 Hz), 7.02 (d, 2 H,
J=8.7 Hz), 6.86 (dd, 1 H, J=8.5 Hz, 2.4 Hz), 6.70 (d, 2 H, J=1.8
Hz), 6.63 (dd, 1 H, J=8.7 Hz, 2.4 Hz), 5.86 (s, 1 H), 5.14 (s, 2
H); MS 407 (M-H).sup.-.
6-(5-Hydroxy-benzofuran-2-yl)-biphenyl-3,4'-diol 105
[0225] A solution of 104 (0.13 g, 0.32 mmol) in MeOH (10 mL) was
treated with 0.2 g 10% Pd/C and cyclohexadiene (1 mL) and stirred
at rt for 24 h. The reaction was filtered through a bed of Celite,
concentrated and chromatographed on silica gel (1:1 EtOAc/hexanes)
and the product was obtained as an oil which crystalized upon
addition of CH.sub.2Cl.sub.2 to yield 48 mg of yellowish needles:
Mp=238-239.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.87 (br
s, 1 H), 9.54 (br s, 1 H), 9.08 (br s, 1 H), 7.64 (d, 1 H, J=8.5
Hz), 7.21 (d, 1 H, J=8.7 Hz), 7.05 (d, 2 H, J=8.4 Hz), 6.84 (dd, 1
H, J=8.5 Hz, 2.5 Hz), 6.76 (d, 2 H, J=8.5 Hz), 6.69 (dd, 2 H, J=6.6
Hz, 2.4 Hz), 6.63 (dd, 1 H, J=8.7 Hz, 2.4 Hz), 5.84 (s, 1H); MS 317
(M-H).sup.-.
Synthesis of Compounds from Scheme 9
2-[5-Hydroxy-4'-(2-pyrrolidin-1-yl-ethoxy)-biphenyl-2-yl]-benzofuran-5-ol
108
[0226] Compound 104 (2.6 g, 6.4 mmol) in DMF (30 mL) was treated
with TBS-CI (2.4 g, 16 mmol) and imidazole (2.2 g, 32 mmol) and
stirred overnight at rt. The reaction was worked up by diluting
with water and washing with brine and drying over MgSO.sub.4. After
filtering, the reaction was concentrated to yield 106 as an oil and
used as is for the next step. This material was dissolved in
THF/EtOH and treated with 10% Pd/C and hydrogenated under an
atmosphere of H.sub.2 for 48 h. The reaction mixture was filtered
through Celite and concentrated to yield 2.9 g of a viscous foam
107 that was used as is for the next step. A solution consisting of
107 (1.25 g, 2.3 mmol) in DMF (25 mL) was treated with
K.sub.2CO.sub.3 (0.64 g, 4.6 mmol) and 2-chloroethyl pyrrolidine
HCl (0.49 g, 8 mmol) and heated at 50.degree. C. for 1 h. Excess
TBAF (1 M in THF) was added and the reaction was allowed to stir
for 15 minutes at rt. The reaction mixture was treated with a
saturated NH.sub.4Cl aq solution followed by saturated NaHCO.sub.3
aq. The reaction was extracted with EtOAc and the EtOAc layer
washed with brine and dried over MgSO.sub.4. After filtration and
concentration, the oily residue was chromatographed on silica gel
(MeOH/CH.sub.2Cl.sub.2 0:100 to MeOH/CH.sub.2Cl.sub.2 5:95). A few
clean fractions were taken from the column and concentrated down to
yield an oil, which was taken up in MeOH and treated with a 1 N HCl
in ether solution and the product precipitated out and was
collected by filtration to give 0.085 g of 108 as the hydrochloride
salt: Mp=266-269.degree. C.; .sup.1H NMR (DMSO-d.sub.6).delta.
10.18 (br s, 1 H), 9.60 (s, 1 H), 9.13 (s, 1 H), 7.79 (d, 1 H,
J=8.7 Hz), 7.24 (d, 1 H, J=8.7 Hz), 7.13-7.08 (m, 3 H), 6.93 (d, 1
H, J=2.6 Hz), 6.79 (d, 2 H, J=8.5 Hz), 6.74 (d, 1 H, J=2.4 Hz),
6.66 (dd, 1 H, J=8.8 Hz, 2.5 Hz), 5.94 (s, 1 H), 4.41 (t, 2 H,
J=4.4 Hz), 3.59 (m, 4 H), 3.14 (m, 2 H), 2.1-1.9 (m, 4 H); MS 414
(M-H).sup.-.
2,2-Dimethyl-propionic acid
2-[4-(2,2-dimethyl-propionyloxy)-phenyl]-benzofuran-5-yl ester
109
[0227] A solution of 75 (8.2 g, 36.3 mmol) in CH.sub.2Cl.sub.2/Pyr
was treated with pivaloyl chloride (9.63 g, 79.9 mmol) and stirred
at rt until TLC indicated that the reaction was complete. The
reaction was worked up by diluting with additional CH.sub.2Cl.sub.2
and washing with 2 N HCl aq. The CH.sub.2Cl.sub.2 layer was washed
with satd NaHCO.sub.3 aq, brine and dried over MgSO.sub.4.
Filtration and concentration yielded 9.3 g of the crude solid that
was used as is for the next reaction.
1-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-3-yl]-ethanone 110
[0228] A solution of the bis-pivaloylate 109 (1 g, 2.54 mmol) in
CH.sub.2Cl.sub.2 was treated with acetyl chloride (0.22 g, 2.8
mmol) was treated with AlCl.sub.3 (0.36 g, 2.8 mmol) and stirred at
rt overnight. The reaction was worked up by adding EtOAc, washing
with 2 N HCl aq, saturated NaHCO.sub.3 aq and drying over
MgSO.sub.4. After filtering and concentrating, the residue was
chromatographed on silica gel (EtOAc/hexanes 1:4 to EtOAc/hexanes
1:1) to yield the product which was promptly dissolved in
MeOH/THF/2 N NaOH aq and warmed until TLC analysis indicated that
the hydrolysis of the pivalate esters was completed. The reaction
was concentrated to remove the organic solvents and the residue
aqueous was acidified with 2 N HCl aq and extracted with EtOAc. The
EtOAc extract was washed with saturated NaHCO.sub.3 solution, brine
and dried over MgSO.sub.4. After filtration and concentration, the
residue was chromatographed on silica gel (EtOAc/hexanes 1:4 to
EtOAc/hexanes 1:1 ) to yield 90 mg of the desired pdt:
Mp=243-251.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.08 (br
s, 1 H), 9.40 (br s, 1 H), 7.63 (d, 2 H, J=8.8 Hz), 7.43 (d, 1 H,
J=9.3 Hz), 7.41 (d, 1 H, J=2.4 Hz), 6.92 (d, 2 H, J=8.8 Hz), 6.80
(dd, 1 H, J=8.8 Hz, 2.4 Hz), 2.26 (s, 3 H).
1-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-3-yl]-ethanone oxime
111
[0229] Ketone 110 (1.9 g, 7.1 mmol) was dissolved in a solution of
EtOH/Pyr (50 mL/10 mL) and treated with NH.sub.2OH--HCl (0.5 g, 7.2
mmol) and heated at reflux until all of the starting material was
consumed by TLC analysis. The reaction was worked up by
concentrating down and partitioning the residue between EtOAc and 2
N HCl aq, washing the EtOAc layer with saturated NaHCO.sub.3 aq,
brine and drying over MgSO.sub.4. The solution was then filtered,
concentrated and chromatographed on silica gel (1:4 EtOAc/hexanes)
and the product obtained triturated with CH.sub.2Cl.sub.2 to yield
0.131 g of the pure oxime. Stereochemistry of the oxime was
tentatively defined as cis since no NOE effect between the oxime
hydroxyl proton and the adjacent methyl group could be observed:
Mp=217.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 11.27 (s, 1
H), 9.94 (br s, 1 H), 9.23 (br s, 1 H), 7.51 (d, 2 H, J=8.8 Hz),
7.36 (d, 1 H, J=8.3 Hz), 7.03 (d, 1 H, J=2.4 Hz), 6.88 (d, 2 H,
J=8.8 Hz), 6.74 (dd, 1 H, J=8.8 Hz, 2.4 Hz), 1.99 (s, 3 H).
3-(1-Hydroxy-ethyl)-2-4-hydroxy-phenyl)benzofuran-5-ol 113
[0230] The bis-acetyl ester 112 (prepared by acetylation of 110 in
pyridine and acetic anhydride) (0.15 g, 0.43 mmol) in EtOH/THF (10
mL/5 mL) was treated with NaBH.sub.4 (0.1 g, 2.6 mmol) and stirred
at rt overnight. The reaction was then treated with 2 N NaOH and
stirred for an additional time until TLC showed that the acetate
hydrolysis had gone to completion. The reaction mixture was
neutralized with saturated NH.sub.4Cl aq and the solution
concentrated. The aqueous residue was extracted with EtOAc and the
EtOAc layer washed with brine, dried over MgSO.sub.4, filtered,
concentrated and chromatographed on silica gel (EtOAc/hexanes 1:4
to EtOAc/hexanes 1:1) to yield 0.040 g of the pdt: Mp=177-
182.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.84 (br s, 1
H), 9.09 (s, 1 H), 7.49 (d, 2 H, J=8.8 Hz), 7.30(d, 1 H, J=8.8 Hz),
7.20 (d, 1 H, J=2.4 Hz), 6.90 (d, 2 H, J=8.8 Hz), 6.69 (dd, 1 H,
J=8.8 Hz, 2.4 Hz), 5.22 (d, 1 H, J=3.4 Hz), 5.10-5.06 (m, 1 H),
1.53 (d, 3 H, J=6.3 Hz); MS 269 (M-H).sup.-.
Synthesis of Compounds from Scheme 10
2-[5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-propan-2-ol
115
[0231] Ester 114 (1.0 g, 3.2 mmol)was treated with Methyl Lithium
(10 ml of 1.0M) in THF (25 ml) at -78.degree. C. After warming to
rt over 2 hr, the rection was quenched with 2NHCl and extracted
with EtOAc. The EtOAc was dried concentrated and the product was
purified by column chromatography on silica gel (20% EtOAct Hexane)
to give 115 as an oil (0.43 g, 43%).
7isopropenyl-5-methoxy-2-(4-methoxy-phenyl)-benzofuran 116
[0232]
2-[5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-propan-2-ol 115
(0.4 g, 1.3 mmol)
[0233]
2-[5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-propan-2-ol 115
(0.4 g, 1.3 mmol), and Burges Reagent (0.4 g, 1.7 mmol) in THF (10
ml) were heated to reflux. After 30 min, the reaction was cooled,
concentrated and the product was purified by column chromatography
on silica gel (10% EtOAc/Hexane) to give 116 as a solid (029 g,
77%).
7-Isopropyl-5-methoxy-2-(4-methoxy-phenyl)-benzofuran 117
[0234] 7-Isopropenyl-5-methoxy-2-(4-methoxy-phenyl)-benzofuran 116
(0.28, 0.95 mmol) was hydrogenated over an atmosphere of hydrogen
with 10% Pd/C (0.05 g) in EtOH/THF (10 ml). After 2 hr, the
reaction was filtered through celite-and concentrated to give 117
as a solid (0.27 g, 95%).
2-(4-Hydroxy-phenyl)-7-isopropyl-benzofuran-5-ol 118
[0235] 7-Isopropyl-5-methoxy-2-(4-methoxy-phenyl)-benzofuran 117
(0.26 g, 0.88 mmol) and Pyridine HCl (5 g) wre heated to
200.degree. C. After 1 hr, the reaction was cooled, diluted with
water and extracted with EtOAc. The organic layer was dried over
MgSO.sub.4, concentrated and the product was purified by column
chromatography on silica gel (25% EtOAc/hexane) to give 118 as a
solid (0.80 g, 34%): Mp=192-194.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.81 (br s, 1 H), 9.03 (br s, 1 H), 7.68 (d,
2 H, J=8.2 Hz), 6.98 (s, 1 H), 6.86 (d, 2 H, J=8.1 Hz), 6.69 (d, 1
H, J=1.4 Hz), 6.54 (d, 1 H, J=1.9 Hz), 3.31 (m, 1 H), 1.32 (d, 6 H,
J=6.9 Hz); MS 269 (M+H).sup.+
5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-carboxylic acid
methoxy-methyl-amide 119
[0236] To a solution of acid 24 (0.35 g, 1.3 mmol), DMAP (0.5 g,
4.1 mmol), N,O Dimethylhydroxyl amine HCl (0.5 g, 5.1 mmol) in DMF
(15 ml) was added EDCl (0.5 g, 2.6 mmol) and the reaction was
stirred at rt for 1 hr. The reaction was then poured into 2N HCl
and extracted with EtOAc, The EtOAc was dried, concentrated, and
the resulting solid was triturated with CH.sub.2Cl.sub.2 and
collected by filtration to give 119 as a white solid (0.22 g, 55%):
Mp=125-127.degree. C; .sup.1NMR
[0237] (DMSO-d.sub.6) .delta. 9.88 (br s, 1 H), 9.44 (s, 1 H),
7.65(d, 2 H, 8.6 Hz), 7.08 (br s, 1 H), 6.97 (d, 1 H, J=2.3 Hz),
6.88 (d, 2 H, J=8.6 Hz), 6.71(dm 1 H, J=2.6 Hz), 3.59 (s,3 H), 3.30
(s, 3H): MS 312 [M-H].sup.-
5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-carbaldehyde 120
[0238] To a cooled (0.degree. C.) solution of 119 (0.18 g, 0.58
mmol) THF (10 ml) was added LiAlH.sub.4 (1.5 ml of 1.0M in THF)
dropwise. After stirring for 30 min, the reaction was quenched with
2N HCl and partitioned between 2N HCl and EtOAc. The EtOAc was
separated, dried, and concentrated. The product was purified by
column chromatography on silica gel (30% EtOAc/Hex) to give 120 as
a yellow solid (0.075 g, 51%); Mp=261-263.degree. C.; .sup.1H NMR
(DMSO-d6) .delta. 10.36 (s,1 H), 9.79 (s, 1 H), 9.77 (s, 1 H), 7.76
(d, 2 H, J=8.5 Hz), 7.25 (d, 1 H, J=2.0 Hz), 7.17 (s, 1 H), 7.12
(d, 1 H, J=2.1 Hz), 6.88 (d, 2 H, J=8.5 Hz); MS 255 (M+H).sup.+
5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-carboxylic acid
methoxy-methyl-amide 121
[0239] A solution of 23 (1.7 g, 5.7 mmol), N,O Dimethylhydroxyamine
HCl (1.7 g, 17.1 mmol), DMAP (2.1 g, 17.1 mmol), and EDCl (1.9 g,
10 mmol) in DMF (30 ml) was stirred at rt for 1 hr. The reaction
was then poured into 2 NHCl and extracted with EtOAc which was
dried over MgSO.sub.4, concentrated, and the product was purified
by column chromatography on silica gel (30% EtOAc/Hex) to give 121
as a solid (1.4 g, 74%); Mp=109-111.degree. C.; .sup.1H NMR
(CDCl.sub.3) .delta. 7.77 (d, 2 H, J=8.7 Hz), 7.09 (d, 1 H, J=2.4
Hz), 6.99-6.95 (m, 3 H), 6.84 (s, 1 H), 3.86 (s, 6 H), 3.69 (s, 3
H), 3.40 (s,3 H); MS 342 (M+H).sup.+
1-[5-Methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-ethanone 122
[0240] To a cooled (-78.degree. C.) solution of 121 (0.6 g, 1.7
mmol) in THF (10 ml) was added Methyl lithium (3.4 ml of 1.0M in
THF) and the reaction was stirred for 1 hr. The solution was then
poured into 2 N HCl and extracted with EtOAc which was separated,
dried over MgSO.sub.4, and concentrated to give a solid which was
triturated with MeOH and collected by filtration to give 122 as a
white solid (0.35 g, 67%); .sup.1H NMR (CDCl.sub.3) .delta. 7.78(d,
2 H, J=8.7 Hz), 7.44 (d, 1 H, 2.6 Hz), 7.24 (s, 1 H), 6.99 (d, 2 H,
J=8.7 Hz), 6.89 (s, 1 H), 3.89 (s, 3 H), 3.88 (s, 3 H), 2.96 (s, 3
H).
1-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-ethanone 123
[0241] A mixture of 122 (0.37 g, 1.3 mmol) and Pyridine HCl (10 g)
was heated to 200.degree. C. After 1 hr, the reaction was cooled,
diluted with water and extracted with EtOAc. The EtOAc layer wad
dried over MgSO.sub.4, concentrated and the product was purified by
column chromatography (50% EtOAc/Hex) to givve 123 as a solid (0.25
g, 74%): Mp=274-276.degree. C.;
[0242] .sup.1H NMR (DMSO-d6) .delta. 9.96 (br s, 1 H), 9.52 (br s,
1 H), 7.74 (d, 2 H, J=8.4 Hz), 7.17-7.16 (m, 3 H), 6.89 (d, 2 H,
J=8.4 Hz), 2.64 (s, 3 H); MS 267 (M-H).sup.-
Synthesis of Compounds from Scheme 11
1-[5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-7-yl]-propan-1-one
124
[0243] To a cooled (0.degree. C.) solution of 121 (0.7 g, 2.0 mmol)
in THF (15 ml) was added Ethyl Magnesium Bromide (6.0 ml of 1.0M in
ether) and the reaction was allowed to warm to rt over 2 hr. The
reaction was then poured into 2N HCl and extracted with EtOAc. The
EtOAc layer was dried concentrated and the product was purified by
column chromatography (15% EtOAc/Hex) to give a solid (0.31 g). To
the solid was added Pyridine HCl (7 g) and the mixture was heated
to 200.degree. C. After 1 Hr, the reaction was cooled, diluted with
water and extracted with EtOAc. The EtOAc layer was dried,
concentrated, and the product was purified by column chromatography
on silica gel (50% EtOAc/Hex) to give 124 as a solid (0.15 g, 26%):
Mp=257-260.degree. C.; .sup.1NMR (DMSO-d.sub.6) .delta. 9.79(br s,
1 H), 9.70(br s, 1 H), 7.76 (d, 2 H, J=8.1 Hz), 7.19-7.15 (m, 3 H),
6.89 (d, 2 H, J=8.1 Hz), 3.32-3.27 (m, 2 H), 1.18 (t, 3 H, J=7.1
Hz); MS 281 [M-H].sup.-
2-(2,5-Dimethoxy-phenyl]-1-(3-fluoro-4-methoxy-phenyl)-ethanone
125
[0244] A solution of 3-F anisole (2 g, 16 mmol) and
2,5-dimethoxyphenacetyl chloride in dichloroethane (50 mL) was
treated with AlCl.sub.3 (2.3 g, 18 mmol) and stirred at rt until
TLC analysis indicated reaction was complete. The reaction was
worked up by adding a 2 N HCl aq solution to the reaction (slowly)
and washing with saturated NaHCO.sub.3 aq, brine and drying over
MgSO.sub.4. After filtering, the EtOAc was concentrated and
chromatographed on silica gel (EtOAc/hexanes 1:4) to yield 1 gram
of the acylated intermediate as well as an isomer as an oily solid
that was used as is for the next reaction step.
2-(3-Fluoro-4-hydroxy-phenyl)-benzofuran-5-ol 126
[0245] The ketone 125 (1 g, 3.3 mmol) was heated with pyr-HCl at
180-200.degree. C. until TLC indicated reaction completion. The
reaction was worked up by partitioning between 2N HCl aq and EtOAc
and washing the EtOAc with saturated NaHCO.sub.3, brine, and drying
over MgSO.sub.4. The solution was filtered, concentrated and
chromatographed on silica gel to yield 0.48 g of impure pdt. The
product thus obtained was recrystallized from EtOAc/hexanes to
yield desired product plus a small amt of unidentified impurity.
Mp=218-222.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 10.39 (s,
1 H), 9.20 (s, 1 H), 7.74 (t, 1 H, J=8.7 Hz), 7.37 (d, 1 H, J=8.8
Hz), 6.96-6.94 (m, 2 H), 6.79-6.70 (m, 3 H); MS 243 (M-H).sup.-
4-(5-Methoxy-benzofuran-2-yl)-benzoic acid methyl ester 127
[0246] A solution of 5-Methoxy-benzofuran-2-boronic acid (1.9 g, 10
mmol), Methyl 4-dobenzoate (2.61 g, 10 mmol), Pd(Ph.sub.3).sub.4
(0.25 g), and 2M NaCO.sub.3 (10 mi) in toluene (40 ml) and EtOH (10
ml) was heated to reflux. After 2 hr, the reaction was cooled and
the organic layer was seperated dried, and concentrated to give a
solid. The solid was triturated with MeOH, filtered to give 127
(0.90 g, 32%) which was used without further purification or
characterization for the next step.
4-(5-Hydroxy-benzofuran-2-yl)-benzoic acid 128
[0247] A mixture of 4-(5-Methoxy-benzofuran-2-yl)-benzoic acid
methyl ester (0.5 g, 1.8 mmol) and Pyridine HCl (5 g) was heated to
200.degree. C. After 2 hr, the reaction was cooled and poured into
water and extracted with EtOAc. The EtOAc layer was dried over
MgSO.sub.4, concentrated and the product was purified by column
chromatography on silica gel (75% EtOAc/hex) to give a solid (0.21
g, 47%): .sup.1H NMR (DMSO-d.sub.6) .delta. 13.07 (br s, 1 H), 9.29
(br s, 1 H), 8.02 (d, 2 H, J=8.1 Hz), 7.97 (d, 2 H, J=8.7 Hz), 7.46
(m, 2 H), 6.97 (d, 1 H, J=2.9 Hz), 6.79 (dd, 1 H, J=9.3 Hz, 2.9
Hz); MS 253 (M-H).sup.-
2-(4-Hydroxymethyl-phenyl)-benzofuran-5-ol 129
[0248] To a solution of 128 (0.15 g, 0.6 mmol), in THF (20 ml) was
added BH.sub.3 (3 ml of 1.0M in THF) and the reaction was heated to
reflux for 3 hr. The reaction was then cooled and poured into 2N
HCl and extracted with EtOAc. The EtOAc was dried over MgSO.sub.4,
filtered and concentrated and triturated with CH.sub.2Cl.sub.2 and
filtered to give 129 as a solid (0.08 g, 57%); .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.21 (br s, 1 H), 7.82 (d, 2 H, J=8.1 Hz),
7.43-7.38 (m, 3 H), 7.24 (s, 1 H), 6.92 (d, 1 H, J=2.1 Hz), 6.73
(dd, 1 H, J=8.5 Hz, 2.6 Hz), 5.28 (t, 1 H, J=5.7 Hz), 4.54 (d, 2 H,
J=5.5 Hz); MS 239 (M-H).sup.-.
Synthesis of Compounds from Scheme 12
4-Bromo-2-(4-hydroxy-phenyl)-benzofuran-5-ol 130
[0249] A solution of 75 2-(4-Hydroxy-phenyl)-benzofuran-5-ol (0.65
g, 2.9 mmol) in CH.sub.3CN (40 mL) was treated with K.sub.2CO.sub.3
(1 g, 7.1 mmol) followed by portionwise addition of NBS (0.36 g,
2.0 mmol). After stirring for approximately 30 minutes, the
reaction was worked up by addition of 2 N HCl followed by10%
Na.sub.2SO.sub.3aq. and then the CH.sub.3CN was stripped off. The
aqueous layer was extracted with EtOAc and washed with brine and
dried over MgSO.sub.4. The reaction mixture was concentrated and
chromatographed on silica gel (EtOAc/hexanes; 1:4): Mp
196-198.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.93 (br s,
2 H), 7.76 (d, 2 H, J=8.5 Hz), 7.40 (d, 1 H, J=8.7 Hz), 7.04 (s, 1
H), 6.87 (dd, 2 H, J=9.0 Hz, 3.1 Hz): MS 305/307 (M+H).sup.+.
4-Chloro-2-(4-hydroxy-phenyl)-benzofuran-5-ol 131
[0250] Prepared analogously to 130 except that NCS was used instead
of NBS: Mp=210-214.degree. C.; .sup.1H NMR (DMSO-d.sub.6) 9.90 (br
s, 1 H), 7.76 (d, 2 H, J=8.5 Hz), 7.13 (s, 1 H), 6.89 (d, 1 H,
J=8.4 Hz), 6.87 (d, 2 H, J=8.5 Hz).
2-(4-Hydroxy-phenyl)-4-methoxy-benzofuran-5-ol 132
[0251] A solution of 4-bromo-2-(4-Hydroxyphenyl)-benzofuran-5-ol
130 (0.100 g, 0.32 mmol) and copper (I) bromide (0.047 g, 0.32
mmol) in DMF (4 mL) was treated with sodium methoxide (0.73 mL, 3.2
mmol, 25% by weight in MeOH) and heated at 150.degree. C. for three
hours under a nitrogen atmosphere. The reaction was quenched at
room temperature with 1 N HCl and extracted with ethyl acetate
(3.times.). The combined organic extracts were washed once with a
saturated sodium bicarbonate solution, then dried over magnesium
sulfate and filtered. Then the material was purified by column
chromatography using 30% ethyl acetate in hexane as the eluent to
yield 132 (0.030 g, 36.6%) as a brown solid: Mp. 165-168.degree.
C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 7.72 (d, 2 H, J=8.6 Hz),
7.23 (s, 1 H), 7.1 (d, 1 H, J=8.7 Hz), 6.86 (d, 2 H, J=8.6 Hz),
6.76 (d, 1 H, J=8.6 Hz), 3.94 (s, 3 H); MS 257 (M+H).sup.+.
4-Bromo-5-methoxy-2-(4-methoxy-phenyl)-benzofuran 133
[0252] 4-Bromo-2-(4-hydroxyphenyl)-benzofuran-5-ol 130 (0.601 g,
1.97 mmol) was taken into 25 mL DMF along with potassium carbonate
(2.72 g, 19.7 mmol) and iodomethane (2.45 mL, 39.4 mmol). The
mixture was heated overnight at 50.degree. C. under a nitrogen
atmosphere. The solution was filtered and the filtrate was diluted
with ethyl acetate and washed with water (3.times.), dried over
magnesium sulfate filtered and concentrated. The resulting material
was purified by column chromatography on silica gel using 10% ethyl
acetate in hexane as the eluent to yield the desired product (0.607
g, 92.5%) as a white solid: Mp. 115-117.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 7.92 (d, 2 H, J=8.8 Hz), 7.60 (d, 1 H, J=8.6
Hz), 7.22 (s, 1 H), 7.09 (d, 1 H, J=8.9 Hz), 7.07 (d, 2 H, J=8.8
Hz), 2.88 (s, 3 H), 3.83 (s, 3 H); MS 333/335 (M+H).sup.+.
5-Methoxy-2-(4-methoxy-phenyl)benzofuran-4-carbonitrile 134
[0253] 4-Bromo-5-methoxy-2-(4-methoxyphenyl)-benzofuran 133 (0.258
g, 0.77 mmol) was taken into 20 mL of DMF along with copper (I)
cyanide (0.173 g, 1.94 mmol) and heated at reflux for three hours.
Additional copper (I) cyanide was added several times to complete
the reaction. The reaction was filtered through a cotton plug that
was then washed several times with ethyl acetate. The filtrate was
diluted with additional ethyl acetate and then washed with water
(2.times.), brine (1.times.), dried over magnesium sulfate,
filtered and concentrated. The resulting material was purified by
column chromatography on silica gel using 10% ethyl acetate in
hexanes as the eluent to yield the desired compound (0.133 g,
61.8%) as a white solid: Mp 120-122.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 7.96 (d, 2 H, J=8.8 Hz), 7.92 (d, 1 H,
J=9.1; Hz), 7.91 (s, 1 H), 7.14 (d, 1 H, J=9.1 Hz), 7.09 (d, 2 H,
J=8.9 Hz), 3.95 (s, 3 H), 3.83 (s, 3 H); MS 280 (M+H).sup.+.
5-Hydroxy-2-(4-hydroxy-phenyl)-benzofuran-4-carbonitrile 135
[0254] 5-Methoxy-2-(4-methoxyphenyl)-benzofuran-4-carbonitrile 134
(0.088 g, 0.31 mmol) was placed in a sealed tube along with
pyridine hydrochloride (enough to fill the volume of the tube by
one-half) and heated at 200.degree. C. for 2.5 hours. The reaction
was dissolved into a mixture of ethyl acetate and 1 N HCl. The
layers were separated and the aqueous layer was extracted with
ethyl acetate (2.times.). The combine organics was washed with 1N
HCl (1.times.), water (1.times.) and then dried over magnesium
sulfate, filtered and concentrated. The resulting material was
purified by column chromatography, using 40% ethyl acetate in
hexanes as the eluent to yield the desired product 135 (0.066 g,
84.7%) as a light brown solid: Mp>230.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 10.89 (s, 1 H), 10.03 (s, 1 H),. 7.82 (d, 2
H, J=8.6 Hz), 7.72 (d, 1 H, J=8.9 Hz), 7.27 (s, 1 H), 6.90 (d, 2 H,
J=8.6 Hz), 6,88 (d, 1 H, J=8.9 Hz).
5-Methoxy-2-(4-methoxy-phenyl)-4-methyl-benzofuran 136
[0255] 4-Bromo-5-methoxy-2-(4-methoxyphenyl)-benzofuran 133 (0.282
g, 0.85 mmol) was taken into 20 mL of THF and cooled to 0.degree.
C. Then butyllithium (0.68 mL of a 2.5M solution in THF, 1.7 mmol)
was added dropwise and allowed to stir for 20 minutes. Then TMEDA
(0.256 mL, 1.7 mmol) was added followed by iodomethane (1.06 mL, 17
mmol). The reaction was allowed to stir overnight at room
temperature. The reaction was poured into water and extracted with
ethyl acetate. The combined organics was washed with water
(2.times.), brine (1.times.), dried over magnesium sulfate filtered
and concentrated. The resulting material was purified by column
chromatography on silica gel, using a gradient of 1% to 3% ethyl
acetate in hexane. The first fractions contained the product and
another side product. This fraction was added to another synthesis
of this compound (starting with 0.250 g
4-Bromo-5-methoxy-2-(4-methoxyphenyl)-benzofuran) for the final
cleavage reaction.
2-(4-Hydroxy-phenyl)-4-methyl-benzofuran-5-ol 137
[0256] The crude 5-Methoxy-2-(4-methoxyphenyl)-4-methylbenzofuran
136 (0.134 g) was taken into a sealed tube along with enough
pyridine hydrochloride to fill the tube halfway and heated at
200.degree. C. for 2.5 hours. The reaction was dissolved into a
mixture of ethyl acetate and 1 N HCl. The layers were separated and
the aqueous layer was extracted with ethyl acetate (2.times.). The
combined organics was washed with 1 N HCl (1.times.), water
(1.times.) and then dried over magnesium sulfate, filtered and
concentrated. The resulting material was purified by column
chromatography on silica gel, using 30% ethyl acetate In hexanes as
the eluent to yield the desired product (0.090 g, 23.4% based on
starting 4-Bromo-5-methoxy-2-(4-methoxyphenyl)-benzofuran from two
runs) as a tan powder: Mp. Mp. 221-222.degree. C.; .sup.1H NMR
(DMSO-d.sub.6) .delta. 9.81 (s, 1 H), 8.94 (s, 1 H), ) 7.70 (d, 2
H, J=8.6 Hz), 7.16 (d, 1 H, J=8.9 Hz), 7.14 (s, 1 H), 6.86 (d, 2 H,
J=8.6 Hz), 6.72 (d, 1 H, J=8.6 Hz), 2.27 (s, 3 H); MS 241
(M+H).sup.+.
2-(4-Hydroxy-phenyl)-7-[1,3,4]oxadiazol-2-yl-benzofuran-5-ol
138
[0257] Compound 24 (0.6 g, 2,2 mmol) in DMF (3-5 mL) and hydrazine
monohydrate (0.25 mL, 5 mmol) was treated with EDCl
(1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) (0.64
g, 3.3 mmol) and the reaction allowed to stir at rt for several
hours. The reaction was worked up by adding water and extracting
twice with EtOAc; The combined EtOAc extracts were washed with
brine and dried over MgSO.sub.4. The EtOAc was concentrated to
render 125 mg of the crude acyl hydrazide which was used as is for
the next step. The crude acyl hydrazide from the previous step was
treated with 3-5 mL of triethyl orthoformate and catalytic
p-toluenesulfonic acid and heated to reflux for 30 minutes. The
reaction mixture was allowed to cool to rt and was poured into 2 N
HCl aq, extracted with EtOAc, washed with 2 N HCl aq, saturated
NaHCO.sub.3 aq, brine, and dried over MgSO.sub.4. Filtration and
concentration followed by chromatography on silica gel (1:19
MeOH/CH.sub.2Cl.sub.2) gave 15 mgs of 138: MP=260-266.degree. C.;
.sup.1H NMR (DMSO-d.sub.6) .delta. 9.94 (br s, 1 H), 9.75 (br s, 1
H), 9.45 (s, 1 H), 7.79 (d, 2 H, J=8.7 Hz), 7.33 (d, 1 H, J=2.4
Hz), 7.20 (s, 1 H), 7.18 (d, 1 H, J=2.4 Hz), 6.92 (d, 2 H, J=8.7
Hz); MS 295 (M+H).sup.+.
Synthesis of Compounds from Scheme 13
2,2,2-Trifluoro-1-[5-methoxy-2-(4-methoxy-phenyl)-benzofuran-7-yl]-ethanol
139
[0258] To a solution of 2 (1.2 g, 4.3 mmol) and
Trimethylsilyltrifluoromethane (20 ml of 0.5M in THF, 10 mmol) in
THF (20 ml) was added TBAF (10 ml of 1.0M in THF, 10 mmol) and the
reaction was stirred at rt. After 30 min, the rextion was poured
into 2N HCl and extracted with ether. The ether was dried,
concentrated and the product was purified by column chromatography
(eluent 10% EtOAc/Hex) to give 139 as a solid (1.2 g, 80%);
Mp=120-122.degree. C.; .sup.1H NMR(CDCl.sub.3) .delta. 7.75 (d, 2
H, J=8.8 Hz), 7.15-6.95 (m, 4 H), 6.84 (s, 1 H), 5.59 (m, 1 H),
3.86 (s, 6,H); MS 353 (M+H).sup.+
5-Methoxy-2-(4-methoxy-phenyl)-7-(2,2,2-trifluoro-ethyl)-benzofuran
140
[0259] To a solution of 139 (1.2 g, 3.4 mmol) in diethyl ether (30
ml) was added NaH (0.41 g, 17 mmol) and the reaction was stirred
for 15 min. P-Tosyl chloride (3.2 g, 17 mmol) was added and the
reaction was stirred for 1 hr. The reaction was carefully poured
into water and extracted with ether which was dried, concentrated
to give an oil which was purified by column chromatography (eluent
10% EtOAc/hex) to give the tosylated intermediate as a white solid.
Mp=113-115.degree. C. A solution of the tosylated intermediate thus
prepared (1.2 g, 2.3 mmol and LiAlH.sub.4 (20 ml of 1.0M, 20 mmol)
in THF (30 ml) was heated to reflux. After 5 hr, the reaction was
cooled, quenched wth 2N HCl and extracted with EtOAc. The organic
layer was added, concentrated and the product was purified by
column chromatography (10 % EtOAc/hex) to give a solid. The solid
was triturated with MeOH and filtered to give 140 as a white solid
(0.060 g, 8%).
2-(4-Hydroxy-phenyl)-7-(2,2,2-trifluoro-ethyl)-benzofuran-5-ol
141
[0260] A mixture of 140 (50 mg, 0.15 mmol) and Pyridine HCl (3 g)
was heated to 200.degree. C. After 1 hr, the reaction was cooled,
diluted with water and extracted with EtOAc. The EtOAc was dried
over MgSO.sub.4, concentrated to give a solid which was triturated
with CH.sub.2Cl.sub.2 and filtered to give 141 (30 mg, 65%):
Mp=210-213.degree. C.; .sup.1H NMR(DMSO-d.sub.6) .delta. 9.86 (s, 1
H), 9.28 (s, 1 H), 7.71(d, 2 H, J=8.8 Hz), 7.05 (s, 1 H), 6.89-6.86
(m, 3 H), 6.69 (d, 1 H, J=2.0 Hz), 3.91-3.84 (m, 2 H); MS 307
[M-H].sup.-
2-(4-Methoxy-phenyl)-benzofuran-5-carboxylic acid methyl ester
142
[0261] A mixture of Methyl 3-Iodo-4-hydroxybenzoate (0.7 g, 2.5
mmol), 4-Methoxyphenylacetylene (0.33 g, 2.5 mmol),
Pd(Cl).sub.2(PPh.sub.3).sub.2 (0.05 g) and CuI (0.03 g) in
DMF/Piperidine (20 ml) was heated at 60.degree. C. After 2 hr, the
reaction was cooled and poured into 2N HCl. The aqueous layer was
extracted with EtOAc and then separated, dried, concentrated to
give a solid. The solid was triturated with MeOH , filtered to give
142 (0.5 g, 71%): Mp 157-159.degree. C.; .sup.1H NMR, (CDCl.sub.3)
.delta. 8.28 (d, 1 H, J=1.3 Hz), 7.97 (dd, 1 H, J=8.5 Hz, 1.7 Hz),
7.82-7.79 (m, 2 H), 7.51(d, 1 H, 8.5 Hz), 6.99 (d, 2 H, J=8.3 Hz),
6.93 (d, 1 H, J=0.9 Hz), 3.94 (s, 3 H), 3.87 (s, 3 H); MS 283
(M+H).sup.+
2-(4-Hydroxy-phenyl)-benzofuran-5-carboxylic acid 143
[0262] A mixture of 142 (0.45 g, 1.6 mmol) and Pyridine HCl (10 g)
was heated to 200.degree. C. After 1 hr, the reaction was cooled
and diluted with water. The aqueous layer was extracted with EtOAc,
dried, concentrated to give a solid which was triturated with
CH.sub.2Cl.sub.2 and filtered to give 143 (0.23 g, 58%):
Mp>300.degree. C.; .sup.1H NMR (DMSO-d.sub.6) .delta. 12.87 (br
s, 1 H), 9.86 (br s, 1 H), 8.21 (d, 1 H, J=1.6 Hz), 7.86 (dd, 1 H,
J=8.8 Hz, 1.5 Hz), 7.76 (d, 2 H, J=8.8 Hz, 7.67 (d, 1 H, J=8.8 Hz),
7.29 (s, 1 H), 6.89 (dd, 2 H, J=7.7 Hz, 2.0 Hz); MS 253
(M-H).sup.-
4-(5-Hydroxymethyl-benzofuran-2-yl)-phenol 144
[0263] Compound 143 (0.21 g, 0.83 mmol) in THF (10 ml) was treated
with BH.sub.3 THF (4.0 ml of 1.0M) and the reaction was heated to
reflux. After 2 hr, the reaction was cooled and then poured into
2NHCl and extracted with EtOAc. The organic layer was dried,
concentrated and the product was purified by cloumn chromatography
(60% EtOAc/Hexane) to give 144 as a solid (0.07 g, 37%);
Mp=248-250.degree.; .sup.1H NMR (DMSO-d.sub.6) .delta. 9.86 (br s,
1 H), 7.72 (d, 2 H, J=8.3 Hz), 7.52-7.49 (m, 2H), 7.19 (dd, 1 H,
J=8.3 Hz, 1.6 Hz), 7.15 (s, 1 H), 6.87 (d, 2 H, J=8.8 Hz), 5.19 (t,
1 H, J=5.2 Hz), 4.56 (d, 2 H, J=4.1 Hz); MS 239 (M-H).sup.-
* * * * *