U.S. patent application number 14/200676 was filed with the patent office on 2014-10-09 for methods for synthesizing molybdopterin precursor z derivatives.
This patent application is currently assigned to Alexion Pharma International Sarl. The applicant listed for this patent is Alexion Pharma International Sarl. Invention is credited to Sylvia Myrna Baars, Andreas Brunner, Keith Clinch, Danmei Dai, Rachel Anne Dixon, Cyrille Abel Sebastien Landreau, Gillian Mary Little, Xiangtian Long, Nicolas George Rene Proisy, Derek Kevin Watt.
Application Number | 20140303367 14/200676 |
Document ID | / |
Family ID | 46672966 |
Filed Date | 2014-10-09 |
United States Patent
Application |
20140303367 |
Kind Code |
A1 |
Long; Xiangtian ; et
al. |
October 9, 2014 |
Methods for Synthesizing Molybdopterin Precursor Z Derivatives
Abstract
Provided herein are synthetic methods for preparing a compound
of formula (I): ##STR00001## Also provided herein are synthetic
methods for preparing a compound of formula (XIII): ##STR00002##
The disclosure also provides useful intermediates, derivatives,
prodrugs, and pharmaceutically acceptable salts, solvates and
hydrates of the formula (I) and formula (XIII) compounds. These
compounds are useful for treating diseases associated with
molybdenum cofactor deficiency.
Inventors: |
Long; Xiangtian; (Guangzhou,
CN) ; Dai; Danmei; (Guangzhou, CN) ; Brunner;
Andreas; (Brig, CH) ; Watt; Derek Kevin;
(Lower Hutt, NZ) ; Clinch; Keith; (Lower Hutt,
NZ) ; Baars; Sylvia Myrna; (Hamilton, NZ) ;
Dixon; Rachel Anne; (Wellington, NZ) ; Little;
Gillian Mary; (Essex, GB) ; Landreau; Cyrille Abel
Sebastien; (Essex, GB) ; Proisy; Nicolas George
Rene; (Hertfordshire, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Alexion Pharma International Sarl |
Lausanne |
|
CH |
|
|
Assignee: |
Alexion Pharma International
Sarl
Lausanne
CH
|
Family ID: |
46672966 |
Appl. No.: |
14/200676 |
Filed: |
March 7, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14000055 |
Mar 24, 2014 |
|
|
|
PCT/US2012/025689 |
Feb 17, 2012 |
|
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14200676 |
|
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|
61599314 |
Feb 15, 2012 |
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|
61498801 |
Jun 20, 2011 |
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61444399 |
Feb 18, 2011 |
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61498808 |
Jun 20, 2011 |
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|
61444280 |
Feb 18, 2011 |
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|
61444389 |
Feb 18, 2011 |
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Current U.S.
Class: |
544/244 |
Current CPC
Class: |
A61P 43/00 20180101;
C07D 491/14 20130101; C07D 491/147 20130101; C07F 9/65744 20130101;
A61P 25/00 20180101 |
Class at
Publication: |
544/244 |
International
Class: |
C07F 9/6574 20060101
C07F009/6574 |
Claims
1. A process for preparing a compound of formula (I): ##STR00224##
or a pharmaceutically acceptable salt thereof, the process
comprising: (a) reacting a compound of formula (II): ##STR00225##
wherein: each R.sub.1 is independently H or a protecting group,
with a compound of formula (III): ##STR00226## to produce a
compound of formula (IV): ##STR00227## (b) selectively protecting
the compound of formula (IV) to prepare a compound of formula (V):
##STR00228## (c) phosphorylating the compound of formula (V) to
prepare a compound of formula (VI): ##STR00229## (d) oxidizing the
compound of formula (VI) to prepare a compound of formula (VII):
##STR00230## and (e) deprotecting the compound of formula (VII) to
prepare the compound of formula (I).
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. Ser. No.
14/000,055, filed Feb. 17, 2012, which is a National Stage
application under 35 U.S.C. .sctn.371 of International Application
No. PCT/US2012/025689, having an International Filing Date of Feb.
17, 2012, which claims priority to U.S. Provisional Application
Ser. No. 61/444,399, filed Feb. 18, 2011; 61/498,801, filed Jun.
20, 2011; 61/444,280, filed Feb. 18, 2011; 61/498,808, filed Jun.
20, 2011; and 61/444,389, filed Feb. 18, 2011; and 61/599,314,
filed Feb. 15, 2012; all of which are incorporated by reference in
their entireties.
TECHNICAL FIELD
[0002] Provided herein are synthetic methods for preparing the
molybdopterin derivative precursor Z and novel synthetic
intermediates useful therein. Also provided herein are useful
intermediates, derivatives, prodrugs, and pharmaceutically
acceptable salts, solvates, and hydrates of precursor Z. These
compounds are useful for, among other things, treating diseases
associated with molybdenum cofactor deficiency.
BACKGROUND
[0003] Molybdenum cofactor (Moco) deficiency is a pleiotropic
genetic disorder. Moco consists of molybdenum covalently bound to
one or two dithiolates attached to a unique tricyclic pterin moiety
commonly referred to as molybdopterin (MPT). Moco is synthesized by
a biosynthetic pathway that can be divided into four steps,
according to the biosynthetic intermediates precursor Z (cyclic
pyranopterin monophosphate; cPMP), MPT, and adenylated MPT.
Mutations in the Moco biosynthetase genes result in the loss of
production of the molybdenum dependent enzymes sulfite-oxidase,
xanthine oxidoreductase, and aldehyde oxidase. Whereas the
activities of all three of these cofactor-containing enzymes are
impaired by cofactor deficiency, the devastating consequences of
the disease can be traced to the loss of sulfite oxidase activity.
Human Moco deficiency is a rare but severe disorder accompanied by
serious neurological symptoms including attenuated growth of the
brain, untreatable seizures, dislocated ocular lenses, and mental
retardation. Until recently, no effective therapy was available and
afflicted patients suffering from Moco deficiency died in early
infancy.
[0004] It has been found that administration of the molybdopterin
derivative precursor Z, a relatively stable intermediate in the
Moco biosynthetic pathway, is an effective means of therapy for
human Moco deficiency and associated diseases related to altered
Moco synthesis (see U.S. Pat. No. 7,504,095). As with most
replacement therapies for illnesses, however, the treatment is
limited by the availability of the therapeutic active agent.
SUMMARY
[0005] Precursor Z (a compound of formula (I) and (XIII)) has
previously been prepared using fermentation processes. These
processes, however, have stability issues, low yields, and are
cost-prohibitive for large-scale production. The following
synthetic processes are proposed as an alternative to these
fermentation processes.
[0006] Provided herein is a process for preparing a compound of
formula (I):
##STR00003##
or a pharmaceutically acceptable salt thereof, the process
comprising: reacting a compound of formula (II):
##STR00004##
wherein each R.sub.1 is independently H or a protecting group, with
a compound of formula (III):
##STR00005##
to produce a compound of formula (IV):
##STR00006##
selectively protecting the compound of formula (IV) to prepare a
compound of formula (V):
##STR00007##
phosphorylating the compound of formula (V) to prepare a compound
of formula (VI):
##STR00008##
oxidizing the compound of formula (VI) to prepare a compound of
formula (VII):
##STR00009##
and deprotecting the compound of formula (VII) to prepare the
compound of formula (I).
[0007] In some embodiments, the pharmaceutically acceptable salt is
an HCl salt. In some embodiments, the pharmaceutically acceptable
salt is an HBr salt.
[0008] In some embodiments, the compound of formula (II) is:
##STR00010##
In some embodiments, the compound of formula (III) is a protected
or unprotected galactose, mannose, glucose, or gulose. For example,
a compound of formula (III) can be:
##STR00011##
In some embodiments, two adjacent R.sub.1 groups come together to
form an isopropylidine acetal or benzylidine acetal moiety.
[0009] In some embodiments, the reaction between the compounds of
formula (II) and (III) comprises reacting the compound of formula
(II) and the compound of formula (III) in the presence of a
hydrazine. For example, the hydrazine can be selected from the
group consisting of phenylhydrazines and alkylhydrazines. In some
embodiments, the hydrazine is phenylhydrazine.
[0010] In some embodiments, the phosphorylation step comprises
reacting the compound of formula (V) with a P(V) phosphorylating
agent. For example, a P(V) phosphorylating agent can be selected
from the group consisting of: POCl.sub.3; H.sub.3PO.sub.4;
PO(OBn).sub.xCl.sub.3-x; Cl.sub.3CCH.sub.2OP(O)Cl.sub.2; and
(BnO).sub.2P(O)OP(O)(OBn).sub.2. In some embodiments, the P(V)
phosphorylating agent is POCl.sub.3. In some embodiments, the
phosphorylation step comprises reacting the compound of formula (V)
with a P(III) phosphitylating agent. For example, the P(III)
phosphitylating agent can be selected from the group consisting of:
P(OCH.sub.2CH.sub.2CN).sub.2Cl;
P(OCH.sub.2CH.sub.2CN)(NPr.sub.2-i)Cl; and
cyanoethyl-O--P[N(i-Pr).sub.2)].sub.2. In some embodiments, the
phosphorylation step further comprises oxidizing the resulting
phosphite to prepare the phosphate of compound (VI).
[0011] In some embodiments, the oxidation step comprises reacting
the compound of formula (VI) with an oxidizing agent selected from
the group consisting of: RuO.sub.4; Dess-Martin; DMSO/triflic
anhydride; and PDC.
[0012] In some embodiments, the deprotection of the compound of
formula (VII) is performed under anaerobic conditions.
[0013] Also provided herein is a process for preparing a compound
of formula (I), or a pharmaceutically acceptable salt thereof, the
process comprising: reacting a compound of formula (II-A):
##STR00012##
with a compound of formula (III-A):
##STR00013##
in the presence of a hydrazine to produce a compound of formula
(IV-A):
##STR00014##
selectively protecting the compound of formula (IV-A) to prepare a
compound of formula (V-A):
##STR00015##
wherein R.sub.1 is a protecting group; phosphorylating the compound
of formula (V-A) to prepare a compound of formula (VI-A):
##STR00016##
oxidizing the compound of formula (VI-A) to prepare a compound of
formula (VII-A):
##STR00017##
and deprotecting the compound of formula (VII-A) to prepare the
compound of formula (I).
[0014] Further provided herein is a process for preparing a
compound of formula (I), or a pharmaceutically acceptable salt
thereof, the process comprising: reacting a compound of formula
(II-A) with a compound of formula (III-A) in the presence of a
hydrazine to produce a compound of formula (IV-A); selectively
protecting the compound of formula (IV-A) to prepare a compound of
formula (V-B):
##STR00018##
wherein each R.sub.1 is independently a protecting group;
phosphorylating the compound of formula (V-B) to prepare a compound
of formula (VI-B):
##STR00019##
oxidizing the compound of formula (VI-B) to prepare a compound of
formula (VII-B):
##STR00020##
and deprotecting the compound of formula (VII-B) to prepare the
compound of formula (I).
[0015] Also provided herein is a process for preparing a compound
of formula (I), or a pharmaceutically acceptable salt thereof,
comprising: reacting a compound of formula (II) with a compound of
formula (VIII):
##STR00021##
wherein each R.sub.1 and R.sub.2 are independently H or a
protecting group; to produce a compound of formula (IX):
##STR00022##
selectively protecting the compound of formula (IX) to prepare a
compound of formula (X):
##STR00023##
wherein R.sub.3 is a protecting group and R.sub.4 is H or a
protecting group; oxidizing the compound of formula (X) to prepare
a compound of formula (XI):
##STR00024##
and deprotecting the compound of formula (XI) to prepare the
compound of formula (I).
[0016] Further provided herein is a process for preparing a
compound of formula (I), or a pharmaceutically acceptable salt
thereof, the process comprising reacting a compound of formula (II)
with a compound of formula (III) to produce a compound of formula
(IV); selectively protecting the compound of formula (IV) to
prepare a compound of formula (V); oxidizing the compound of
formula (V) to prepare a compound of formula (XII):
##STR00025##
phosphorylating the compound of formula (XII) to prepare a compound
of formula (VII); and deprotecting the compound of formula (VII) to
prepare the compound of formula (I).
[0017] This disclosure also provides a process for preparing a
compound of formula (I), or a pharmaceutically acceptable salt
thereof, the process comprising: reacting a compound of formula
(II) with a compound of formula (XXII):
##STR00026##
wherein each R.sub.1 is independently H or a protecting group, to
produce a compound of formula (IV); selectively protecting the
compound of formula (IV) to prepare a compound of formula (V);
phosphorylating the compound of formula (V) to prepare a compound
of formula (VI); oxidizing the compound of formula (VI) to prepare
a compound of formula (VII); and deprotecting the compound of
formula (VII) to prepare the compound of formula (I).
[0018] In some embodiments, the compound of formula (II) is:
##STR00027##
[0019] In some embodiments, the compound of formula (XXII) is:
##STR00028##
[0020] In some embodiments, the phosphorylation step comprises
reacting the compound of formula (V) with a P(V) phosphorylating
agent. For example, a P(V) phosphorylating agent can be selected
from the group consisting of: POCl.sub.3; H.sub.3PO.sub.4;
PO(OBn).sub.xCl.sub.3-x; Cl.sub.3CCH.sub.2OP(O)Cl.sub.2; and
(BnO).sub.2P(O)OP(O)(OBn).sub.2. In some embodiments, the P(V)
phosphorylating agent is Cl.sub.2PO(OCH.sub.3).
[0021] In some embodiments, the oxidation step comprises reacting
the compound of formula (VI) with an oxidizing agent selected from
the group consisting of: RuO.sub.4; Dess-Martin; DMSO/triflic
anhydride; DMSO/TFAA; and PDC.
[0022] In some embodiments, the deprotection of the compound of
formula (VII) is performed under anaerobic conditions.
[0023] Further provided herein is a process for preparing a
compound of formula (I), or a pharmaceutically acceptable salt
thereof, the process comprising: reacting a compound of formula
(II-A):
##STR00029##
with a compound of formula (XXII-A):
##STR00030##
in the presence of a base to produce a compound of formula
(W-A):
##STR00031##
selectively protecting the compound of formula (IV-A) to prepare a
compound of formula (V-C):
##STR00032##
wherein each R.sub.1 is independently H or a protecting group,
phosphorylating the compound of formula (V-C) to prepare a compound
of formula (VI-C):
##STR00033##
oxidizing the compound of formula (VI-C) to prepare a compound of
formula (VII-C):
##STR00034##
and deprotecting the compound of formula (VII-C) to prepare the
compound of formula (I).
[0024] This disclosure also provides a process for preparing a
compound of formula (I), or a pharmaceutically acceptable salt
thereof, the process comprising: reacting a compound of formula
(XXIII):
##STR00035##
wherein each R.sub.1 is independently H or a protecting group and
R.sub.4 is H or a leaving group; to produce a compound of formula
(XXIV):
##STR00036##
reacting a compound of formula (XXIV) with a compound of formula
(II) to produce a compound of formula (XXV):
##STR00037##
catalyzing ring formation of the compound of formula (XXV) to
produce a compound of formula (IV); selectively protecting the
compound of formula (IV) to prepare a compound of formula (V);
phosphorylating the compound of formula (V) to prepare a compound
of formula (VI); oxidizing the compound of formula (VI) to prepare
a compound of formula (VII); and deprotecting the compound of
formula (VII) to prepare the compound of formula (I).
[0025] In some embodiments, the compound of formula (XXIII) is
selected from the group consisting of:
##STR00038##
[0026] In some embodiments, the compound of formula (XXIV) can
be:
##STR00039##
[0027] In some embodiments, the compound of formula (XXV) is:
##STR00040##
[0028] In some embodiments, the phosphorylation step comprises
reacting the compound of formula (V) with a P(V) phosphorylating
agent. For example, a P(V) phosphorylating agent can be selected
from the group consisting of: POCl.sub.3; H.sub.3PO.sub.4;
PO(OBn).sub.xCl.sub.3-x; Cl.sub.3CCH.sub.2OP(O)Cl.sub.2; and
(BnO).sub.2P(O)OP(O)(OBn).sub.2. In some embodiments, the P(V)
phosphorylating agent is Cl.sub.2PO(OCH.sub.3).
[0029] In some embodiments, the oxidation step comprises reacting
the compound of formula (VI) with an oxidizing agent selected from
the group consisting of: RuO.sub.4; Dess-Martin; DMSO/triflic
anhydride; DMSO/TFAA; and PDC.
[0030] In some embodiments, the deprotection of the compound of
formula (VII) is performed under anaerobic conditions.
[0031] In some embodiments, the compound of formula (XXIII) is:
##STR00041##
[0032] In some embodiments, the compound of formula (XXIV) is:
##STR00042##
[0033] In some embodiments, the compound formula (XXV) is:
##STR00043##
[0034] In some embodiments, a leaving group is selected from the
group consisting of: tosylates, brosylates, nosylates, mesylates,
oxoniums, triflates, nonaflates, and tresylates.
[0035] Also provided herein is a process for preparing a compound
of formula (I), or a pharmaceutically acceptable salt thereof, the
process comprising: reacting a compound of formula (XXIII-A).
##STR00044##
wherein: each R.sub.1 is independently H or a protecting group, and
R.sub.4 is H or a leaving group, to produce a compound of formula
(XXIV):
##STR00045##
reacting a compound of formula (XXIV) with a compound of formula
(II-A):
##STR00046##
to produce a compound of formula (XXV-A):
##STR00047##
catalyzing ring formation of the compound of formula (XXV-A) to
produce a compound of formula (IV-D):
##STR00048##
selectively protecting the compound of formula (IV-D) to prepare a
compound of formula (V-D):
##STR00049##
phosphorylating the compound of formula (V-D) to prepare a compound
of formula (VI-D):
##STR00050##
oxidizing the compound of formula (VI-D) to prepare a compound of
formula (VII-D):
##STR00051##
and deprotecting the compound of formula (VII-D) to prepare the
compound of formula (I).
[0036] This disclosure also provides a process for preparing a
compound of formula (I), or a pharmaceutically acceptable salt
thereof, the process comprising: oxidizing the compound of formula
(VI) to prepare a compound of formula (VII); and deprotecting the
compound of formula (VII) to prepare the compound of formula
(I).
[0037] In some embodiments, a compound of formula (I), or a
pharmaceutically acceptable salt thereof, can be prepared by
phosphorylating the compound of formula (V) to prepare a compound
of formula (VI); oxidizing the compound of formula (VI) to prepare
a compound of formula (VII); and deprotecting the compound of
formula (VII) to prepare the compound of formula (I).
[0038] Also provided herein is a process for preparing a compound
of formula (I), or a pharmaceutically acceptable salt thereof, the
process comprising: selectively protecting the compound of formula
(IV) to prepare a compound of formula (V); phosphorylating the
compound of formula (V) to prepare a compound of formula (VI);
oxidizing the compound of formula (VI) to prepare a compound of
formula (VII); and deprotecting the compound of formula (VII) to
prepare the compound of formula (I).
[0039] In some embodiments, the processes described above further
comprise formulating the compound of formula (I) as a
pharmaceutical composition.
[0040] Further provided herein is a compound of formula (I), or a
pharmaceutically acceptable salt thereof, prepared by any of the
processes described above. In some embodiments, a pharmaceutical
composition is provided comprising a compound of formula (I), or a
pharmaceutically acceptable salt thereof, prepared by any of the
processes described above and a pharmaceutically acceptable
excipient.
[0041] This disclosure also provides a process for preparing a
compound of formula (XIII):
##STR00052##
or a pharmaceutically acceptable salt form thereof, the process
comprising: reacting a compound of formula (II):
##STR00053##
wherein each R.sub.1 is independently H or a protecting group, with
a compound of formula (III):
##STR00054##
to produce a compound of formula (IV):
##STR00055##
selectively protecting the compound of formula (IV) to prepare a
compound of formula (V):
##STR00056##
phosphorylating the compound of formula (V) to prepare a compound
of formula (VI):
##STR00057##
oxidizing the compound of formula (VI) to prepare a compound of
formula (XIV):
##STR00058##
and (e) deprotecting the compound of formula (XIV) to prepare the
compound of formula (XIII).
[0042] Also provided herein is a process for preparing a compound
of formula (XIII), or a pharmaceutically acceptable salt thereof,
the process comprising: reacting a compound of formula (II) with a
compound of formula (VIII):
##STR00059##
wherein each R.sub.1 and R.sub.2 is H or a protecting group, to
produce a compound of formula (IX):
##STR00060##
selectively protecting the compound of formula (IX) to prepare a
compound of formula (X):
##STR00061##
wherein R.sub.3 is a protecting group and R.sub.4 is H or a
protecting group; oxidizing the compound of formula (X) to prepare
a compound of formula (XV):
##STR00062##
and deprotecting the compound of formula (XV) to prepare the
compound of formula (XIII).
[0043] Further provided herein is a process for preparing a
compound of formula (XIII), or a pharmaceutically acceptable salt
thereof, the process comprising: reacting a compound of formula
(II) with a compound of formula (III) to produce a compound of
formula (IV); selectively protecting the compound of formula (IV)
to prepare a compound of formula (V); phosphorylating the compound
of formula (V) to prepare a compound of formula (VI); oxidizing the
compound of formula (VI) to prepare a compound of formula (XIV);
and deprotecting the compound of formula (XIV) to prepare the
compound of formula (XIII).
[0044] This disclosure also provides a process for preparing a
compound of formula (XIII), or a pharmaceutically acceptable salt
form thereof, the process comprising: oxidizing the compound of
formula (VI) to prepare a compound of formula (XIV); and
deprotecting the compound of formula (XIV) to prepare the compound
of formula (XIII).
[0045] In some embodiments, a compound of formula (XIII), or a
pharmaceutically acceptable salt thereof, is prepared
phosphorylating the compound of formula (V) to prepare a compound
of formula (VI); oxidizing the compound of formula (VI) to prepare
a compound of formula (XIV); and deprotecting the compound of
formula (XIV) to prepare the compound of formula (XIII).
[0046] Also provided herein is a process for preparing a compound
of formula (XIII), or a pharmaceutically acceptable salt form
thereof, the process comprising: selectively protecting the
compound of formula (IV) to prepare a compound of formula (V);
phosphorylating the compound of formula (V) to prepare a compound
of formula (VI); oxidizing the compound of formula (VI) to prepare
a compound of formula (XIV); and deprotecting the compound of
formula (XIV) to prepare the compound of formula (XIII).
[0047] This disclosure also provides a process for preparing a
compound of formula (XIII), or a pharmaceutically acceptable salt
thereof, the process comprising: reacting a compound of formula
(II) with a compound of formula (XXII) to produce a compound of
formula (IV); selectively protecting the compound of formula (IV)
to prepare a compound of formula (V); phosphorylating the compound
of formula (V) to prepare a compound of formula (VI); oxidizing the
compound of formula (VI) to prepare a compound of formula (XIV);
and deprotecting the compound of formula (XIV) to prepare the
compound of formula (XIII).
[0048] Also provided herein is a process for preparing a compound
of formula (XIII), or a pharmaceutically acceptable salt thereof,
the process comprising: reacting a compound of formula (XXIII) to
produce a compound of formula (XXIV); reacting a compound of
formula (XXIV) with a compound of formula (II) to produce a
compound of formula (XXV); catalyzing ring formation of the
compound of formula (XXV) to produce a compound of formula (IV);
selectively protecting the compound of formula (IV) to prepare a
compound of formula (V); phosphorylating the compound of formula
(V) to prepare a compound of formula (VI); oxidizing the compound
of formula (VI) to prepare a compound of formula (XIV); and
deprotecting the compound of formula (XIV) to prepare the compound
of formula (XIII).
[0049] In some embodiments, the processes described above further
comprise formulating the compound of formula (XIII) as a
pharmaceutical composition.
[0050] Further provided herein is a compound of formula (XIII)
prepared by any of the processes described above. In some
embodiments, a pharmaceutical composition is provided comprising a
compound of formula (XIII), or a pharmaceutically acceptable salt
thereof, prepared by any of the processes described above and a
pharmaceutically acceptable excipient.
[0051] This disclosure also provides a compound of formula
(IV):
##STR00063##
or a pharmaceutically acceptable salt form thereof, wherein each
R.sub.1 is independently H or a protecting group. For example, a
compound of formula (IV) can be:
##STR00064##
or a pharmaceutically acceptable salt form thereof. In some
embodiments, the compound of formula (IV) is:
##STR00065##
Also provided herein is a compound of formula (V):
##STR00066##
or a pharmaceutically acceptable salt form thereof, wherein each
R.sub.1 is independently H or a protecting group. For example, a
compound of formula (V) can be selected from the group consisting
of:
##STR00067##
or a pharmaceutically acceptable salt form thereof. In some
embodiments, a compound of formula (V) is selected from the group
consisting of:
##STR00068##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (V) is:
##STR00069##
[0052] Further provided herein is a compound of formula (VI):
##STR00070##
or a pharmaceutically acceptable salt form thereof, wherein each
R.sub.1 is independently H or a protecting group. For example, a
compound of formula (VI) can be selected from the group consisting
of:
##STR00071##
or a pharmaceutically acceptable salt form thereof. In some
embodiments, a compound of formula (VI) is selected from the group
consisting of:
##STR00072##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound formula (VI) is:
##STR00073##
[0053] Provided herein is a compound of formula (VII):
##STR00074##
or a pharmaceutically acceptable salt form thereof, wherein each
R.sub.1 is independently H or a protecting group. For example, a
compound of formula (VII) is selected from the group consisting
of:
##STR00075##
or a pharmaceutically acceptable salt form thereof. In some
embodiments, a compound of formula (VII) is selected from the group
consisting of:
##STR00076##
or a pharmaceutically acceptable salt form thereof. In some
embodiments, the compound of formula (VII) is:
##STR00077##
[0054] This disclosure also provides a process of preparing a
compound of formula (XXIV):
##STR00078##
or a pharmaceutically acceptable salt thereof, wherein each R.sub.1
is H or a protecting group, the method comprising: reacting a
compound of formula (XXIII):
##STR00079##
wherein R.sub.1 is H or a protecting group and R.sub.4 is H or a
leaving group, with a base to prepare a compound of formula
(XXIV).
DESCRIPTION OF DRAWINGS
[0055] FIG. 1 shows bar graphs illustrating the in vitro synthesis
of Moco using both synthetic precursor Z (cPMP) and precursor Z
(cPMP) prepared and purified from a fermentation process.
[0056] FIG. 2 provides the data from three repetitions of in vitro
synthesis of MPT from synthetic precursor Z (cPMP).
[0057] FIG. 3 provides the data from three repetitions of in vitro
synthesis of MPT from precursor Z (cPMP) prepared and purified from
a fermentation process using E. coli.
DETAILED DESCRIPTION
[0058] It is appreciated that certain features of the disclosure,
which are, for clarity, described in the context of separate
embodiments, can also be provided in combination in a single
embodiment. Conversely, various features of the disclosure which
are, for brevity, described in the context of a single embodiment,
can also be provided separately or in any suitable
subcombination.
[0059] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as is commonly understood by one
of ordinary skill in the art to which this disclosure belongs. All
patents, applications, published applications, and other
publications cited herein are incorporated by reference in their
entirety. In the event that there is a plurality of definitions for
terms cited herein, those in this section prevail unless otherwise
stated.
[0060] For the terms "for example" and "such as," and grammatical
equivalences thereof, the phrase "and without limitation" is
understood to follow unless explicitly stated otherwise. As used
herein, the term "about" is meant to account for variations due to
experimental error. All measurements reported herein are understood
to be modified by the term "about", whether or not the term is
explicitly used, unless explicitly stated otherwise. As used
herein, the singular forms "a," "an," and "the" include plural
referents unless the context clearly dictates otherwise.
[0061] The term "salt" includes any ionic form of a compound and
one or more counter-ionic species (cations and/or anions). Salts
also include zwitterionic compounds (i.e., a molecule containing
one more cationic and anionic species, e.g., zwitterionic amino
acids). Counter ions present in a salt can include any cationic,
anionic, or zwitterionic species. Exemplary anions include, but are
not limited to: chloride, bromide, iodide, nitrate, sulfate,
bisulfate, sulfite, bisulfite, phosphate, acid phosphate,
perchlorate, chlorate, chlorite, hypochlorite, periodate, iodate,
iodite, hypoiodite, carbonate, bicarbonate, isonicotinate, acetate,
trichloroacetate, trifluoroacetate, lactate, salicylate, citrate,
tartrate, pantothenate, bitartrate, ascorbate, succinate, maleate,
gentisinate, fumarate, gluconate, glucaronate, saccharate, formate,
benzoate, glutamate, methanesulfonate, trifluoromethanesulfonate,
ethanesulfonate, benzenesulfonate, p-toluenesulfonate,
p-trifluoromethylbenzenesulfonate, hydroxide, aluminates, and
borates. Exemplary cations include, but are not limited to:
monovalent alkali metal cations, such as lithium, sodium,
potassium, and cesium, and divalent alkaline earth metals, such as
beryllium, magnesium, calcium, strontium, and barium. Also included
are transition metal cations, such as gold, silver, copper and
zinc, as well as non-metal cations, such as ammonium salts.
[0062] The term "prodrug," as used herein, refers to a compound
which, upon administration to a subject, undergoes chemical
conversion by metabolic or chemical processes to yield, e.g., the
compounds described herein, and/or a salt and/or solvate thereof.
The term "prodrugs" can include esters and carbonates formed, for
example, by reacting one or more hydroxyl groups of the compounds
described herein with alkyl, alkoxy, or aryl substituted acylating
agents employing procedures known to those skilled in the art to
generate, e.g., the corresponding acetates, pivalates,
methylcarbonates, and benzoates. For example, compounds containing
a carboxy group can form physiologically hydrolyzable esters which
serve as prodrugs by being hydrolyzed in the body to yield the
compounds provided herein. Such prodrugs can be administered orally
since hydrolysis in many instances occurs under the influence of
the digestive enzymes. Parenteral administration may also be used,
e.g., in situations where hydrolysis occurs in the blood.
[0063] The term "solvate" is used herein to describe a molecular
complex comprising a compound provided herein and a stoichiometric
amount of one or more pharmaceutically acceptable solvent
molecules, for example, ethanol. The term "hydrate" is employed
when the solvent is water. Typical procedures for making and
identifying hydrates and solvates are described on pages 202-209 of
K. J. Guillory, "Generation of Polymorphs, Hydrates, Solvates, and
Amorphous Solids," in: Polymorphism in Pharmaceutical Solids, ed.
Harry G. Brittan, Vol. 95, Marcel Dekker, Inc., New York, 1999,
which is incorporated by reference herein in its entirety.
[0064] As used herein, chemical structures which contain one or
more stereocenters depicted with dashed and bold bonds (i.e., ) are
meant to indicate absolute stereochemistry of the stereocenter(s)
present in the chemical structure. As used herein, bonds symbolized
by a simple line do not indicate a stereo-preference. Unless
otherwise indicated to the contrary, chemical structures, which
include one or more stereocenters, illustrated herein without
indicating absolute or relative stereochemistry encompass all
possible stereoisomeric forms of the compound (e.g., diastereomers,
enantiomers) and mixtures thereof. Structures with a single bold or
dashed line, and at least one additional simple line, encompass a
single enantiomeric series of all possible diastereomers.
[0065] Resolution of racemic mixtures of compounds can be carried
out by any of numerous methods known in the art. An exemplary
method includes fractional recrystallization using a chiral
resolving acid which is an optically active, salt-forming organic
acid. Suitable resolving agents for fractional recrystallization
methods are, for example, optically active acids, such as the D and
L forms of tartaric acid, diacetyltartaric acid, dibenzoyltartaric
acid, mandelic acid, malic acid, lactic acid, or the various
optically active camphorsulfonic acids such as camphorsulfonic
acid. Other resolving agents suitable for fractional
crystallization methods include stereoisomeric ally pure forms of
methylbenzylamine (e.g., S and R forms, or diastereomerically pure
forms), 2-phenylglycinol, norephedrine, ephedrine,
N-methylephedrine, cyclohexylethylamine, 1,2-diaminocyclohexane,
and the like.
[0066] Resolution of racemic mixtures can also be carried out by
elution on a column packed with an optically active resolving agent
(e.g., dinitrobenzoylphenylglycine). Suitable elution solvent
compositions can be determined by one skilled in the art.
[0067] Compounds provided herein can also include all isotopes of
atoms occurring in the intermediates or final compounds. Isotopes
include those atoms having the same atomic number but different
mass numbers. For example, isotopes of hydrogen include hydrogen,
tritium, and deuterium.
[0068] The term, "compound," as used herein is meant to include all
stereoisomers, geometric isomers, tautomers, and isotopes of the
structures depicted. Compounds herein identified by name or
structure as one particular tautomeric form are intended to include
other tautomeric forms unless otherwise specified.
[0069] All compounds, and pharmaceutically acceptable salts
thereof, can be found together with other substances such as water
and solvents (e.g., hydrates and solvates).
[0070] In some embodiments, the compounds provided herein, or salts
thereof, are substantially isolated. By "substantially isolated" is
meant that the compound is at least partially or substantially
separated from the environment in which it was formed or detected.
Partial separation can include, for example, a composition enriched
in the compounds provided herein. Substantial separation can
include compositions containing at least about 50%, at least about
60%, at least about 70%, at least about 80%, at least about 90%, at
least about 95%, at least about 97%, or at least about 99% by
weight of the compounds provided herein, or salt thereof. Methods
for isolating compounds and their salts are routine in the art.
[0071] The phrase "pharmaceutically acceptable" is employed herein
to refer to those compounds, materials, compositions, and/or dosage
forms which are, within the scope of sound medical judgment,
suitable for use in contact with the tissues of human beings and
animals without excessive toxicity, irritation, allergic response,
or other problem or complication, commensurate with a reasonable
benefit/risk ratio.
[0072] The expressions, "ambient temperature" and "room
temperature," as used herein, are understood in the art, and refer
generally to a temperature, e.g. a reaction temperature, that is
about the temperature of the room in which the reaction is carried
out, for example, a temperature from about 20.degree. C. to about
30.degree. C.
[0073] Also provided herein are pharmaceutically acceptable salts
of the compounds described herein. As used herein,
"pharmaceutically acceptable salts" refers to derivatives of the
disclosed compounds wherein the parent compound is modified by
converting an existing acid or base moiety to its salt form.
Examples of pharmaceutically acceptable salts include, but are not
limited to, mineral or organic acid salts of basic residues such as
amines; alkali or organic salts of acidic residues such as
carboxylic acids; and the like. The pharmaceutically acceptable
salts of the compounds provided herein include the conventional
non-toxic salts of the parent compound formed, for example, from
non-toxic inorganic or organic acids. The pharmaceutically
acceptable salts of the compounds provided herein can be
synthesized from the parent compound which contains a basic or
acidic moiety by conventional chemical methods. Generally, such
salts can be prepared by reacting the free acid or base forms of
these compounds with a stoichiometric amount of the appropriate
base or acid in water or in an organic solvent, or in a mixture of
the two; in some embodiments, a non-aqueous media like ether, ethyl
acetate, alcohols (e.g., methanol, ethanol, iso-propanol, or
butanol) or acetonitrile (ACN) can be used. Lists of suitable salts
are found in Remington's Pharmaceutical Sciences, 17th ed., Mack
Publishing Company, Easton, Pa., 1985, p. 1418 and Journal of
Pharmaceutical Science, 66, 2 (1977), each of which is incorporated
herein by reference in its entirety. Conventional methods for
preparing salt forms are described, for example, in Handbook of
Pharmaceutical Salts: Properties, Selection, and Use, Wiley-VCH,
2002.
Synthesis
[0074] The compounds provided herein, including salts thereof, can
be prepared using known organic synthesis techniques and can be
synthesized according to any of numerous possible synthetic
routes.
[0075] The reactions for preparing the compounds provided herein
can be carried out in suitable solvents which can be readily
selected by one of skill in the art of organic synthesis. Suitable
solvents can be substantially non-reactive with the starting
materials (reactants), the intermediates, or products at the
temperatures at which the reactions are carried out, e.g.,
temperatures which can range from the solvent's freezing
temperature to the solvent's boiling temperature. A given reaction
can be carried out in one solvent or a mixture of more than one
solvent. Depending on the particular reaction step, suitable
solvents for a particular reaction step can be selected by the
skilled artisan.
[0076] Preparation of the compounds provided herein can involve the
protection and deprotection of various chemical groups. The need
for protection and deprotection, and the selection of appropriate
protecting groups, can be readily determined by one skilled in the
art. The chemistry of protecting groups can be found, for example,
in Protecting Group Chemistry, 1.sup.st Ed., Oxford University
Press, 2000; March's Advanced Organic Chemistry: Reactions,
Mechanisms, and Structure, 5.sup.th Ed., Wiley-Interscience
Publication, 2001; and Peturssion, S. et al., "Protecting Groups in
Carbohydrate Chemistry," J. Chem. Educ., 74(11), 1297 (1997) (each
of which is incorporated herein by reference in its entirety).
[0077] Reactions can be monitored according to any suitable method
known in the art. For example, product formation can be monitored
by spectroscopic means, such as nuclear magnetic resonance
spectroscopy (e.g., .sup.1H or .sup.13C), infrared spectroscopy,
spectrophotometry (e.g., UV-visible), mass spectrometry, or by
chromatographic methods such as high performance liquid
chromatography (HPLC), liquid chromatography-mass spectroscopy
(LCMS), or thin layer chromatography (TLC). Compounds can be
purified by those skilled in the art by a variety of methods,
including high performance liquid chromatography (HPLC)
("Preparative LC-MS Purification: Improved Compound Specific Method
Optimization" K. F. Blom, et al., J. Combi. Chem. 6(6), 874 (2004),
which is incorporated herein by reference in its entirety) and
normal phase silica chromatography.
[0078] The compound of formula (I), and other useful compounds and
intermediates, can be formed as shown in Scheme 1. For example, a
diaminopyrimidinone compound of formula (II) can be reacted with a
protected or unprotected hexose sugar of formula (III) to give a
compound of formula (IV). The ring nitrogen atoms of the piperizine
ring of formula (IV) can then be selectively protected using
standard conditions to give a derivative of formula (V).
Phosphorylation of the compound of formula (V) can furnish a
phosphate intermediate of formula (VI). The phosphate of formula
(VI) can be converted to a diol of formula (VII) under appropriate
oxidation conditions. Finally, the compound of formula (VII) can be
deprotected to give the compound of formula (I).
##STR00080## ##STR00081##
Compounds of Formula (II):
[0079] In some embodiments, the preparation of compounds of formula
(II) is contemplated:
##STR00082##
wherein each R.sub.1 is independently H or a protecting group.
[0080] Formula (II) can include, for example, the compound
2,5,6-triaminopyrimidin-4(3H)-one:
##STR00083##
and salts and derivatives thereof. In some embodiments, a compound
of formula (II) can be in the form of a hydrochloride salt:
##STR00084##
[0081] As indicated, certain functional groups of the formula (II)
structure (e.g., the amino group, the 2-position of the pyrimidine
ring, and the ring nitrogen atom at the 3-position) may be
protected with an R.sub.1 protecting group. For this purpose,
R.sub.1 may include any suitable amino protecting groups,
including, but not limited to, carbamate, amide, N-alkyl, or
N-aryl-derived protecting groups. The R.sub.1 protecting groups may
be the same or different.
[0082] In particular, the carbamate protecting group may include,
for example, 9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate
(Boc), carboxybenzyl carbamate (cbz), methyl carbamate, ethyl
carbamate, 9-(2-sulfo)fluorenylmethyl carbamate,
9-(2,7-dibromo)fluorenylmethyl carbamate,
17-tetrabenzo[a,c,g,i]fluorenylmethyl carbamate (Tbfmoc),
2-chloro-3-indenylmethyl carbamate (Climoc),
2,7-di-t-butyl[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methyl
carbamate (DBD-Tmoc), 1,1-dioxobenzo[b]thiophene-2-ylmethyl
carbamate (Bsmoc), 2,2,2-trichloroethyl carbamate (Troc),
2-trimethylsilylethyl carbamate (Teoc), 2-phenylethyl carbamate
(hZ), 1,1-dimethyl-2-haloethyl carbamate,
1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-boc),
1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBoc),
1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc),
N-2-pivaloylamino)-1,1-dimethylethyl carbamate,
2-[(2-nitrophenyl)dithio]-1-phenylethyl carbamate (NpSSPeoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, 1-adamantyl
carbamate (1-Adoc), vinyl carbamate (Voc), 1-isopropylallyl
carbamate (Ipaoc), 4-nitrocinnamyl carbamate (Noc),
3-(3'pyridyl)prop-2-enyl carbamate (Paloc), 8-quinolyl carbamate,
alkyldithio carbamate, p-methoxybenzyl carbamate (Moz),
p-nitrobenzyl carbamate (Pnz), p-bromobenzyl carbamate,
p-chlorobenzyl carbamate, 2,4-dichlorobenzyl carbamate,
4-methylsulfinylbenzyl carbamate (Msz), diphenylmethyl carbamate,
2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,
2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methyl
carbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),
2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonoethyl carbamate
(Peoc), 1,1-dimethyl-2-cyanoethyl carbamate, 2-(4-nitrophenyl)ethyl
carbamate, 4-phenylacetoxybenzyl carbamate (PhAcOZ), and
m-chloro-p-acyloxybenzyl carbamate. In some embodiments, the
carbamate protecting group is chosen from 9-fluorenylmethyl
carbamate (Fmoc), t-butyl carbamate (Boc), and carboxybenzyl
carbamate (cbz).
[0083] The amide protecting group may include, for example,
acetamide, phenylacetamide, 3-phenylpropanamide, pent-4-enamide,
picolinamide, 3-pyridylcarboxamide, benzamide, p-phenylbenzamide,
2-methyl-2-(o-phenylazophenoxy)propanamide), 4-chlorobutanamide,
acetoacetamide, 3-(p-hydroxyphenyl)propanamide), and
(N'-dithiobenzyloxycarbonylamino)acetamide.
[0084] Compounds of formula (II) can be prepared using known
methods, such as those described by Sharma et al., Indian Journal
of Chemistry, Section B: Organic Chemistry Including Medicinal
Chemistry, 43B, 385 (2004). For example, the
2,5,6-triaminoprimidin-4(3H)-one is prepared as shown in Scheme
2.
##STR00085##
[0085] Compounds of formula (II) can also include the tautomeric
structure:
##STR00086##
or a salt thereof
Compounds of Formula (III):
[0086] Another embodiment of this disclosure provides the
preparation of compounds of formula (III):
##STR00087##
wherein each R.sub.1 is independently H or a protecting group.
[0087] Formula (III) can include, for example, protected or
unprotected hexose sugars. For example, a hexose sugar of formula
(III) can include glucose, mannose, galactose, allose, altrose,
gulose, idose, talose, and derivatives thereof. The hexoses can be
in D or L form. For example, the following hexoses are included
within the scope of formula (III):
##STR00088##
In some embodiments, the hexose is a protected or unprotected
glucose or galactose. For example, the compound of formula (III)
can be a protected or unprotected galactose (e.g., D-galactose). In
some embodiments, the hexose is a protected or unprotected gulose
or galactose.
[0088] As indicated, the compound of formula (III) may be in the
form of a free sugar (i.e., an unprotected monosaccharide).
Alternatively, certain hydroxyl groups of the formula (III)
structure (e.g., the hydroxyl groups at the 3, 4, and 5-positions
of the hexose) may be protected with an R.sub.1 protecting group.
For this purpose, R.sub.1 may include any suitable hydroxyl
functional group including, but not limited to, ether, ester,
carbonate, or sulfonate protecting groups. The R.sub.1 protecting
groups may be the same or different.
[0089] In particular, the ether protecting group may include
methyl, methoxy methyl (MOM), benzyloxymethyl (BOM),
methoxyethoxymethyl (MEM), 2-(trimethylsilyl)ethoxymethyl (SEM),
methylthiomethyl (MTM), phenylthiomethyl (PTM), azidomethyl,
cyanomethyl, 2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl,
2-bromoethyl, tetrahydropyranyl (THP), 1-ethoxyethyl (EE),
phenacyl, 4-bromophenacyl, cyclopropylmethyl, allyl, propargyl,
isopropyl, cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl,
4-methoxybenzyl (MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl,
3,4-dichlorobenzyl, 4-(dimethylamino)carbonylbenzyl,
4-methylsulfinylbenzyl (Msib), 9-anthrylmethyl, 4-picolyl,
heptafluoro-p-tolyl, tetrafluoro-4-pyridyl, trimethylsilyl (TMS),
t-butyldimethylsilyl (TBDMS), t-butyldiphenylsilyl (TBDPS), and
triisopropylsilyl (TIPS) protecting groups.
[0090] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0091] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0092] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0093] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0094] In some embodiments, two adjacent R.sub.1 groups come
together to form an isopropylidine acetal, benzylidine acetal,
1,5-dioxaspiro[5.5]undecane (cyclohexylidene acetal),
6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, the R.sub.1
groups at the 4- and 5-positions of the hexose sugar can combine to
form one or more of the following protected hexoses:
##STR00089##
[0095] Compounds of formula (III) may be prepared according to
known methods of carbohydrate synthesis. Methods of protecting
carbohydrates are also known, as described in The Organic Chemistry
of Sugars, Taylor & Francis, 2006, p. 181; and Peturssion, S.
et al., J. Chem. Educ., 74(11), 1297 (1997), each of which is
incorporated herein by reference in its entirety.
[0096] As will be recognized by persons of ordinary skill in the
art, and as discussed, infra, the stereochemistry of the formula
(III) structure may govern the stereochemistry of subsequent
intermediates in the synthesis of formula (I) or formula (XIII).
Moreover, protection of certain hydroxyl groups can improve
solubility of the formula (III) compounds and modulate
stereospecificity of successive reaction steps.
Compounds of Formula (IV):
[0097] Another embodiment provided herein relates to the
preparation of compounds of formula (IV):
##STR00090##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group.
[0098] As indicated, the amino and hydroxyl groups in the compound
of formula (IV) may be in protected or unprotected form. For
example, in an unprotected form, the compound for formula (IV) may
include the compound
2-amino-6,7-dihydroxy-8-(hydroxymethyl)-5a,6,7,8,9a,10-hexahydro-3H-pyran-
o[3,2-g]pteridin-4(5H)-one:
##STR00091##
or a pharmaceutically acceptable salt, thereof.
[0099] Certain amino and/or hydroxyl groups of the formula (IV)
structure may be protected with an R.sub.1 protecting group. For
this purpose, R.sub.1 may include any suitable amino or hydroxyl
functional group chosen by a person skilled in the chemical arts.
For example, amino protecting groups within the scope of the
present disclosure include, but are not limited to, carbamate,
amide, N-alkyl, or N-aryl-derived protecting groups. Non-limiting
examples of hydroxyl protecting groups may include ether, ester,
carbonate, or sulfonate protecting groups. The R.sub.1 protecting
groups may be the same or different.
[0100] In particular, the carbamate protecting group may include,
for example, 9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate
(Boc), carboxybenzyl carbamate (cbz), methyl carbamate, ethyl
carbamate, 9-(2-sulfo)fluorenylmethyl carbamate,
9-(2,7-dibromo)fluorenylmethyl carbamate,
17-tetrabenzo[a,c,g,i]fluorenylmethyl carbamate (Tbfmoc),
2-chloro-3-indenylmethyl carbamate (Climoc),
2,7-di-t-butyl[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methyl
carbamate (DBD-Tmoc), 1,1-dioxobenzo[b]thiophene-2-ylmethyl
carbamate (Bsmoc), 2,2,2-trichloroethyl carbamate (Troc),
2-trimethylsilylethyl carbamate (Teoc), 2-phenylethyl carbamate
(hZ), 1,1-dimethyl-2-haloethyl carbamate,
1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-boc),
1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBoc),
1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc),
N-2-pivaloylamino)-1,1-dimethylethyl carbamate,
2-[(2-nitrophenyl)dithio]-1-phenylethyl carbamate (NpSSPeoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, 1-adamantyl
carbamate (1-Adoc), vinyl carbamate (Voc), 1-isopropylallyl
carbamate (Ipaoc), 4-nitrocinnamyl carbamate (Noc),
3-(3'pyridyl)prop-2-enyl carbamate (Paloc), 8-quinolyl carbamate,
alkyldithio carbamate, p-methoxybenzyl carbamate (Moz),
p-nitrobenzyl carbamate (Pnz), p-bromobenzyl carbamate,
p-chlorobenzyl carbamate, 2,4-dichlorobenzyl carbamate,
4-methylsulfinylbenzyl carbamate (Msz), diphenylmethyl carbamate,
2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,
2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methyl
carbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),
2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonoethyl carbamate
(Peoc), 1,1-dimethyl-2-cyanoethyl carbamate, 2-(4-nitrophenyl)ethyl
carbamate, 4-phenylacetoxybenzyl carbamate (PhAcOZ), and
m-chloro-p-acyloxybenzyl carbamate. In some embodiments, the
carbamate protecting group is chosen from 9-fluorenylmethyl
carbamate (Fmoc), t-butyl carbamate (Boc), and carboxybenzyl
carbamate (cbz) protecting groups.
[0101] The amide protecting group may include, for example,
acetamide, phenylacetamide, 3-phenylpropanamide, pent-4-enamide,
picolinamide, 3-pyridylcarboxamide, benzamide, p-phenylbenzamide,
2-methyl-2-(o-phenylazophenoxy)propanamide), 4-chlorobutanamide,
acetoacetamide, 3-(p-hydroxyphenyl)propanamide), and
(N'-dithiobenzyloxycarbonylamino)acetamide.
[0102] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0103] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0104] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0105] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0106] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0107] In some embodiments, two adjacent R.sub.1 groups come
together to form an isopropylidine acetal, benzylidine acetal,
1,5-dioxaspiro[5.5]undecane (cyclohexylidene acetal),
6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, the R.sub.1
groups at the 4- and 5-positions of the hexose ring component of
formula (IV) can combine to form an isopropylidine acetal,
benzylidine acetal, 1,5-dioxaspiro[5.5]undecane (cyclohexylidene
acetal), 6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety.
[0108] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (IV) compounds. For example, preparation
of acetyl derivatives of formula (IV) can improve solubility and
increase product isolation yield.
[0109] A compound of formula (IV) may be prepared by reacting a
compound of formula (II):
##STR00092##
with a compound of formula (III):
##STR00093##
to produce a compound of formula (IV):
##STR00094##
wherein: each R.sub.1 is independently H or a protecting group, as
defined above.
[0110] In particular, a compound of formula (IV) may be prepared
upon reaction of a compound of formula (II) and formula (III) in
the presence of any reagent which would achieve the desired
cyclization. Such a reagent can be readily determined by the
skilled person and can include, for example, substituted or
unsubstituted hydrazines. Non-limiting examples of suitable
hydrazine reagents include phenylhydrazines and alkylhydrazines,
for example, phenylhydrazine and p-nitrophenylhydrazine.
[0111] As will be understood, the isomeric form of the formula (IV)
structure may govern the stereospecificity of subsequent
intermediates in the successive steps of the synthesis of formula
(I) or formula (XIII). Accordingly, a particular isomer may be
isolated at this step of the synthesis or, alternatively, isomeric
mixtures of formula (IV) may be carried through and isolated at
later stages of the synthesis.
[0112] In some embodiments, the compound of formula (IV) includes
the isomer:
##STR00095##
or pharmaceutically acceptable salts or hydrates thereof.
[0113] During the synthesis, the stereochemistry of the formula
(IV) product may optionally be controlled by manipulating the
stereochemistry of the C-3 and C-4 positions of the formula (III)
hexose. For example, formula (III) reactants derived from glucose,
mannose, galactose, allose, altrose, gulose, idose, and talose, and
derivatives which differ with respect to the stereochemistry of the
C-3 and C-4 positions of the sugar will produce different isomer
mixtures of the formula (IV) product.
[0114] The stereoselectivity of the formula (IV) synthesis can also
be controlled by incorporating bulky protecting groups at certain
positions of the formula (III) compound. For example, introducing
an isopropylidine acetal at any of the C-3, C-4, or C-5 positions
of the formula (III) sugar can modulate stereoselectivity of the
reaction.
Compounds of Formula (V):
[0115] Another embodiment provided herein relates to the
preparation of compounds of formula (V):
##STR00096##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group. For example,
the compound of formula (V) includes the compound (V-A), (V-B), and
(V-C):
##STR00097##
or a pharmaceutically acceptable salt thereof, wherein R.sub.1 is H
or a protecting group. The compound of formula (V) also includes,
for example, the compound (9H-fluoren-9-yl)methyl
2-amino-6,7-dihydroxy-8-(hydroxymethyl)-4-oxo-5a,6,7,8,9a,10-hexahydro-3H-
-pyrano[3,2-g]pteridine-5(4H)-carboxylate:
##STR00098##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (V) can include, for example, one or more
of the following compounds:
##STR00099##
or a pharmaceutically acceptable salt thereof. For example, a
compound of formula (V) can include one or more of:
##STR00100##
or a pharmaceutically acceptable salt thereof.
[0116] In some embodiments, one or more of the above compounds can
be separated by those skilled in the art by a variety of methods,
including high performance liquid chromatography (HPLC)
("Preparative LC-MS Purification: Improved Compound Specific Method
Optimization" K. F. Blom, et al., J. Combi. Chem. 6(6), 874 (2004),
which is incorporated herein by reference in its entirety) and
normal phase silica chromatography.
[0117] As indicated, certain amino and/or hydroxyl groups of the
formula (V) structure may be protected with an R.sub.1 protecting
group. For this purpose, R.sub.1 may include any suitable amino or
hydroxyl functional group chosen by a person skilled in the
chemical arts. For example, amino protecting groups within the
scope of the present disclosure include, but are not limited to,
carbamate, amide, N-alkyl, or N-aryl-derived protecting groups.
Non-limiting examples of hydroxyl protecting groups may include
ether, ester, carbonate, or sulfonate protecting groups. The
R.sub.1 protecting groups may be the same or different.
[0118] In particular, the carbamate protecting group may include,
for example, 9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate
(Boc), carboxybenzyl carbamate (cbz), methyl carbamate, ethyl
carbamate, 9-(2-sulfo)fluorenylmethyl carbamate,
dibromo)fluorenylmethyl carbamate,
17-tetrabenzo[a,c,g,i]fluorenylmethyl carbamate (Tbfmoc),
2-chloro-3-indenylmethyl carbamate (Climoc),
2,7-di-t-butyl[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methyl
carbamate (DBD-Tmoc), 1,1-dioxobenzo[b]thiophene-2-ylmethyl
carbamate (Bsmoc), 2,2,2-trichloroethyl carbamate (Troc),
2-trimethylsilylethyl carbamate (Teoc), 2-phenylethyl carbamate
(hZ), 1,1-dimethyl-2-haloethyl carbamate,
1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-boc),
1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBoc),
1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc),
N-2-pivaloylamino)-1,1-dimethylethyl carbamate,
2-[(2-nitrophenyl)dithio]-1-phenylethyl carbamate (NpSSPeoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, 1-adamantyl
carbamate (1-Adoc), vinyl carbamate (Voc), 1-isopropylallyl
carbamate (Ipaoc), 4-nitrocinnamyl carbamate (Noc),
3-(3'pyridyl)prop-2-enyl carbamate (Paloc), 8-quinolyl carbamate,
alkyldithio carbamate, p-methoxybenzyl carbamate (Moz),
p-nitrobenzyl carbamate (Pnz), p-bromobenzyl carbamate,
p-chlorobenzyl carbamate, 2,4-dichlorobenzyl carbamate,
4-methylsulfinylbenzyl carbamate (Msz), diphenylmethyl carbamate,
2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,
2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methyl
carbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),
2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonoethyl carbamate
(Peoc), 1,1-dimethyl-2-cyanoethyl carbamate, 2-(4-nitrophenyl)ethyl
carbamate, 4-phenylacetoxybenzyl carbamate (PhAcOZ), and
m-chloro-p-acyloxybenzyl carbamate. In some embodiments, the
carbamate protecting group is chosen from 9-fluorenylmethyl
carbamate (Fmoc), t-butyl carbamate (Boc), and carboxybenzyl
carbamate (cbz) protecting groups.
[0119] The amide protecting group may include, for example,
acetamide, phenylacetamide, 3-phenylpropanamide, pent-4-enamide,
picolinamide, 3-pyridylcarboxamide, benzamide, p-phenylbenzamide,
2-methyl-2-(o-phenylazophenoxy)propanamide), 4-chlorobutanamide,
acetoacetamide, 3-(p-hydroxyphenyl)propanamide), and
(N'-dithiobenzyloxycarbonylamino)acetamide.
[0120] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0121] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0122] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0123] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0124] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0125] In some embodiments, two adjacent R.sub.1 groups come
together to form an isopropylidine acetal, benzylidine acetal,
1,5-dioxaspiro[5.5]undecane (cyclohexylidene acetal),
6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, the R.sub.1
groups at the 4- and 5-positions of the hexose ring component of
formula (V) can combine to form an an isopropylidine acetal,
benzylidine acetal, 1,5-dioxaspiro[5.5]undecane (cyclohexylidene
acetal), 6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety.
[0126] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (V) compounds. For example, preparation
of acetyl derivatives of formula (V) can improve solubility and
increase product isolation yield.
[0127] A compound of formula (V) may be prepared by selectively
protecting a compound of formula (IV):
##STR00101##
to prepare a compound of formula (V):
##STR00102##
wherein: each R.sub.1 is independently H or a protecting group, as
defined above.
[0128] In particular, a compound of formula (V) may be prepared by
reacting a compound of formula (IV) with any reagent and using
conditions to achieve selective installation of the R.sub.1
protecting group at N-5. Suitable reagents and conditions for
installing the R.sub.1 protecting group can be readily determined
by those of ordinary skill in the art. For example,
9-fluorenylmethyl carbamate (Fmoc) can be installed using an
activated chloride derivative, as reported by E. Atherton et al.,
"The Fluorenylmethoxycarbonyl Amino Protecting Group," in The
Peptides, S. Udenfriend and J. Meienhofer, Eds., Academic Press,
New York, 1987, Vol. 9, page 1. Protection using t-butyl carbamate
(Boc) is attained by reacting a compound of formula (IV) with, for
example, (Boc).sub.2O in aqueous NaOH as described by D. Tarbell et
al., Proc. Natl. Acad. Sci., USA, 69, 730 (1972). Methyl and ethyl
carbamate can be readily introduced as described by E. J. Corey et
al., Tetrahedron Lett., 19(12), 1051 (1978).
[0129] As will be understood, the isomeric form of the formula (V)
structure may govern the stereospecificity of subsequent
intermediates in the successive steps of the synthesis of formula
(I) or formula (XIII). Accordingly, a particular isomer may be
isolated at this step of the synthesis or, alternatively, isomeric
mixtures of formula (V) may be carried through and isolated at
later stages of the synthesis.
[0130] In some embodiments, the compound of formula (V) includes
the isomer:
##STR00103##
In addition, as shown above, the compound of formula (V) also
includes the tautomeric structure:
##STR00104##
or a salt thereof.
Compounds of Formula (VI):
[0131] In another embodiment, compounds of formula (VI) are
prepared:
##STR00105##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group. For example,
the compound for formula (VI) includes the compound (VI-A):
##STR00106##
or a pharmaceutically acceptable salt thereof, wherein R.sub.1 is H
or a protecting group. The compound of formula (VI) also includes,
for example, the compound:
##STR00107##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (VI) includes, for example, the compound
(VI-B):
##STR00108##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (VI) includes, for example, the compound
(VI-C):
##STR00109##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (VI) can include one or more of:
##STR00110##
or a pharmaceutically acceptable salt thereof. For example, a
compound of formula (VI) can include one or more of the
following:
##STR00111##
or a pharmaceutically acceptable salt thereof. In some embodiments,
one or more of the above compounds can be separated by those
skilled in the art by a variety of methods, including high
performance liquid chromatography (HPLC) ("Preparative LC-MS
Purification: Improved Compound Specific Method Optimization" K. F.
Blom, et al., J. Combi. Chem. 6(6), 874 (2004), which is
incorporated herein by reference in its entirety) and normal phase
silica chromatography.
[0132] As indicated, certain amino and/or hydroxyl groups of the
formula (VI) structure may be protected with an R.sub.1 protecting
group. For this purpose, R.sub.1 may include any suitable amino or
hydroxyl functional group chosen by a person skilled in the
chemical arts. For example, amino protecting groups within the
scope of the present disclosure include, but are not limited to,
carbamate, amide, N-alkyl, or N-aryl-derived protecting groups.
Non-limiting examples of hydroxyl protecting groups may include
ether, ester, carbonate, or sulfonate protecting groups. The
R.sub.1 protecting groups may be the same or different.
[0133] In particular, the carbamate protecting group may include,
for example, 9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate
(Boc), carboxybenzyl carbamate (cbz), methyl carbamate, ethyl
carbamate, 9-(2-sulfo)fluorenylmethyl carbamate,
9-(2,7-dibromo)fluorenylmethyl carbamate,
17-tetrabenzo[a,c,g,i]fluorenylmethyl carbamate (Tbfmoc),
2-chloro-3-indenylmethyl carbamate (Climoc),
2,7-di-t-butyl[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methyl
carbamate (DBD-Tmoc), 1,1-dioxobenzo[b]thiophene-2-ylmethyl
carbamate (Bsmoc), 2,2,2-trichloroethyl carbamate (Troc),
2-trimethylsilylethyl carbamate (Teoc), 2-phenylethyl carbamate
(hZ), 1,1-dimethyl-2-haloethyl carbamate,
1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-boc),
1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBoc),
1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc),
N-2-pivaloylamino)-1,1-dimethylethyl carbamate,
2-[(2-nitrophenyl)dithio]-1-phenylethyl carbamate (NpSSPeoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, 1-adamantyl
carbamate (1-Adoc), vinyl carbamate (Voc), 1-isopropylallyl
carbamate (Ipaoc), 4-nitrocinnamyl carbamate (Noc),
3-(3'pyridyl)prop-2-enyl carbamate (Paloc), 8-quinolyl carbamate,
alkyldithio carbamate, p-methoxybenzyl carbamate (Moz),
p-nitrobenzyl carbamate (Pnz), p-bromobenzyl carbamate,
p-chlorobenzyl carbamate, 2,4-dichlorobenzyl carbamate,
4-methylsulfinylbenzyl carbamate (Msz), diphenylmethyl carbamate,
2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,
2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methyl
carbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),
2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonoethyl carbamate
(Peoc), 1,1-dimethyl-2-cyanoethyl carbamate, 2-(4-nitrophenyl)ethyl
carbamate, 4-phenylacetoxybenzyl carbamate (PhAcOZ), and
m-chloro-p-acyloxybenzyl carbamate. In some embodiments, a
carbamate protecting group can be chosen from 9-fluorenylmethyl
carbamate (Fmoc), t-butyl carbamate (Boc), and carboxybenzyl
carbamate (cbz) protecting groups.
[0134] The amide protecting group may include, for example,
acetamide, phenylacetamide, 3-phenylpropanamide, pent-4-enamide,
picolinamide, 3-pyridylcarboxamide, benzamide, p-phenylbenzamide,
2-methyl-2-(o-phenylazophenoxy)propanamide), 4-chlorobutanamide,
acetoacetamide, 3-(p-hydroxyphenyl)propanamide), and
(N'-dithiobenzyloxycarbonylamino)acetamide.
[0135] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0136] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0137] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0138] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0139] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0140] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (VI) compounds. For example, preparation
of acetyl derivatives of formula (VI) can improve solubility and
increase product isolation yield.
[0141] A compound of formula (VI) may be prepared by
phosphorylating a compound of formula (V):
##STR00112##
to prepare a compound of formula (VI):
##STR00113##
or a pharmaceutically acceptable salt form thereof, wherein each
R.sub.1 is independently H or a protecting group, as defined
above.
[0142] In particular, a compound of formula (VI) may be prepared by
reacting a compound of formula (V) with any phosphorylating agent
proper to form a compound of formula (VI). Suitable phosphorylation
reagents and conditions can be readily determined by those of
ordinary skill in the art. For example, a compound of formula (VI)
may be achieved by treating a compound of formula (V) with a P(V)
phosphorylating agent. Suitable P(V) phosphorylating agents
include, but are not limited to, POCl.sub.3, H.sub.3PO.sub.4,
PO(OBn).sub.xCl.sub.3-x, Cl.sub.3CCH.sub.2OP(O)Cl.sub.2,
PO(OCH.sub.3).sub.xCl.sub.3-x, PO(OCH.sub.3)Cl.sub.2,
PO(OCH.sub.3).sub.xCl.sub.3-x, PO(OCH.sub.3)Cl.sub.2, and
(BnO).sub.2P(O)OP(O)(OBn).sub.2. In some embodiments, the P(V)
phosphorylating agent is POCl.sub.3.
[0143] In one embodiment, the phosphorylation reaction is carried
out by treating a compound of formula (V) with POCl.sub.3 at
ambient temperature to afford a compound of formula (VI). In
another embodiment, a compound of formula (VI) is formed by
treating a compound of formula (V) with POCl.sub.3 at 60.degree.
C.
[0144] The phosphorylation reaction may also involve treating a
compound of formula (V) with a P(III) phosphitylating agent to form
a phosphite intermediate. Suitable P(III) phosphitylating agents
include, for example, P(OCH.sub.2CH.sub.2CN).sub.2Cl;
P(OCH.sub.2CH.sub.2CN)(NPr.sub.2-i)Cl; and
cyanoethyl-O--P[N(i-Pr).sub.2)].sub.2. When a P(III)
phosphitylating agent is used for phosphorylation, subsequent
oxidation may be used to furnish the corresponding phosphate. When
P(III) reagents are employed for the synthesis of a compound of
formula (VI), Boc or Cbz groups may be used for R.sub.1 protection
of the N-5 of the compound of formula (IV) due to the basic
environment used for phosphitylation.
[0145] As will be understood, the isomeric form of the formula (VI)
structure may regulate the stereospecificity of successive steps in
the synthesis of formula (I). Accordingly, a particular isomer may
be isolated at this step of the synthesis or, alternatively,
isomeric mixtures of a compound of formula (VI) may be carried
through and isolated at later stages of the synthesis.
[0146] In some embodiments, the compound of formula (VI) includes
the isomer:
##STR00114##
As shown above, the compound of formula (VI) can also include the
tautomeric structure.
##STR00115##
or a salt thereof
Compounds of Formula (VII):
[0147] In another embodiment, compounds of formula (VII) are
prepared:
##STR00116##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group. For example,
the compound for formula (VII) includes the compound (VII-A):
##STR00117##
or a pharmaceutically acceptable salt thereof, wherein R.sub.1 is H
or a protecting group. The compound of formula (VII) also includes,
for example, the compound:
##STR00118##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (VII) includes the compound (VII-B):
##STR00119##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (VII) includes the compound (VII-C):
##STR00120##
or a pharmaceutically acceptable salt thereof. In some embodiments,
a compound of formula (VII) can include one or more of the
following:
##STR00121##
or a pharmaceutically acceptable salt thereof. For example, a
compound of formula (VII) can include one or more of the
following:
##STR00122##
or a pharmaceutically acceptable salt thereof. In some embodiments,
one or more of the above compounds can be separated by those
skilled in the art by a variety of methods, including high
performance liquid chromatography (HPLC) ("Preparative LC-MS
Purification: Improved Compound Specific Method Optimization" K. F.
Blom, et al., J. Combi. Chem. 6(6), 874 (2004), which is
incorporated herein by reference in its entirety) and normal phase
silica chromatography.
[0148] As indicated, certain amino and/or hydroxyl groups of the
formula (VII) structure may be protected with an R.sub.1 protecting
group. For this purpose, R.sub.1 may include any suitable amino or
hydroxyl functional group chosen by a person skilled in the
chemical arts. For example, amino protecting groups within the
scope of the present disclosure include, but are not limited to,
carbamate, amide, N-alkyl, or N-aryl-derived protecting groups.
Non-limiting examples of hydroxyl protecting groups may include
ether, ester, carbonate, or sulfonate protecting groups. The
R.sub.1 protecting groups may be the same or different.
[0149] In particular, the carbamate protecting group may include,
for example, 9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate
(Boc), carboxybenzyl carbamate (cbz), methyl carbamate, ethyl
carbamate, 9-(2-sulfo)fluorenylmethyl carbamate,
9-(2,7-dibromo)fluorenylmethyl carbamate,
17-tetrabenzo[a,c,g,i]fluorenylmethyl carbamate (Tbfmoc),
2-chloro-3-indenylmethyl carbamate (Climoc),
2,7-di-t-butyl[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methyl
carbamate (DBD-Tmoc), 1,1-dioxobenzo[b]thiophene-2-ylmethyl
carbamate (Bsmoc), 2,2,2-trichloroethyl carbamate (Troc),
2-trimethylsilylethyl carbamate (Teoc), 2-phenylethyl carbamate
(hZ), 1,1-dimethyl-2-haloethyl carbamate,
1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-boc),
1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBoc),
1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc),
N-2-pivaloylamino)-1,1-dimethylethyl carbamate,
2-[(2-nitrophenyl)dithio]-1-phenylethyl carbamate (NpSSPeoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, 1-adamantyl
carbamate (1-Adoc), vinyl carbamate (Voc), 1-isopropylallyl
carbamate (Ipaoc), 4-nitrocinnamyl carbamate (Noc),
3-(3'pyridyl)prop-2-enyl carbamate (Paloc), 8-quinolyl carbamate,
alkyldithio carbamate, p-methoxybenzyl carbamate (Moz),
p-nitrobenzyl carbamate (Pnz), p-bromobenzyl carbamate,
p-chlorobenzyl carbamate, 2,4-dichlorobenzyl carbamate,
4-methylsulfinylbenzyl carbamate (Msz), diphenylmethyl carbamate,
2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,
2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methyl
carbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),
2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonoethyl carbamate
(Peoc), 1,1-dimethyl-2-cyanoethyl carbamate, 2-(4-nitrophenyl)ethyl
carbamate, 4-phenylacetoxybenzyl carbamate (PhAcOZ), and
m-chloro-p-acyloxybenzyl carbamate. In some embodiments, the
carbamate protecting group is chosen from 9-fluorenylmethyl
carbamate (Fmoc), t-butyl carbamate (Boc), and carboxybenzyl
carbamate (cbz) protecting groups.
[0150] The amide protecting group may include, for example,
acetamide, phenylacetamide, 3-phenylpropanamide, pent-4-enamide,
picolinamide, 3-pyridylcarboxamide, benzamide, p-phenylbenzamide,
2-methyl-2-(o-phenylazophenoxy)propanamide), 4-chlorobutanamide,
acetoacetamide, 3-(p-hydroxyphenyl)propanamide), and
(N'-dithiobenzyloxycarbonylamino)acetamide.
[0151] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0152] The ester protecting group may include acetate, aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate.
[0153] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0154] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0155] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0156] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (VII) compounds. For example, preparation
of acetyl derivatives of formula (VII) compounds can improve
solubility and increase product isolation yield.
[0157] A compound of formula (VII) may be prepared by oxidizing the
compound of formula (VI):
##STR00123##
to prepare a compound of formula (VII):
##STR00124##
wherein: each R.sub.1 is independently H or a protecting group, as
defined above.
[0158] In this synthesis, a compound of formula (VII) may be
prepared by reacting a compound of formula (VI) with any oxidizing
agent proper to selectively form the diol of formula (VII).
Suitable oxidizing agents and conditions can be readily determined
by those of ordinary skill in the art. For example, a compound of
formula (VII) may be formed upon treatment of a compound of formula
(VI) with a ruthenium compound, such as RuO.sub.4.sup.-/NMO. Other
oxidants, such as Dess-Martin's reagent, DMSO/triflic anhydride,
TFAA/DMSO, PDC, hydrogen peroxide, inorganic peroxides, nitric
acid, nitrates, chlorite, chlorate, perchlorate, hypochlorite,
peroxide, iodine, ozone, nitrous oxide, silver oxide, permanganate
salts, hexavalent chromium compounds, chromic acid, dichromic
acids, chromium trioxide, pyridinium chlorochromate, persulfuric
acid, sulfoxides, sulfuric acid, Tollens' reagent,
2,2'-dipyridyldisulfide (DPS), and osmium tetroxide may also be
used. In one embodiment, the oxidation conditions are performed so
that the pyrazine ring of compound (VI) is not oxidized. In some
embodiments, the oxidizing agent is chosen from
RuO.sub.4.sup.-/NMO, Dess-Martin's reagent, DMSO/triflic anhydride,
and PDC.
[0159] For example, the oxidation reaction may be carried out by
treating a compound of formula (VI) with RuO.sub.4.sup.-/NMO at
ambient temperature to afford a compound of formula (VII). In
another embodiment, a compound of formula (VII) is formed by
treating a compound of formula (VI) with RuO.sub.4.sup.-/NMO at a
temperature from 20-60.degree. C., or at 20, 25, 30, 35, 40, 45,
50, or 55.degree. C.
[0160] A compound of formula (VII) can be used to prepare a
compound of formula (XIV) via dehydration. Suitable reaction
conditions for such a dehydration reaction are readily determined
by those of ordinary skill in the art. For example, a compound of
formula (VII) can be combined with a concentrated acid or base to
prepare a compound of formula (XIV). In some embodiments, any of
the oxidation methods provided herein can include the further step
of dehydrating the reaction product to obtain the corresponding
ketone.
[0161] As will be understood, the isomeric form of the formula
(VII) structure may regulate the stereospecificity of successive
steps in the synthesis of formula (I). Accordingly, a particular
isomer may be isolated at this step of the synthesis or,
alternatively, isomeric mixtures of a compound of formula (VII) may
be carried through and isolated at later stages of the
synthesis.
[0162] In some embodiments, the compound of formula (VII) includes
the isomer:
##STR00125##
or a pharmaceutically acceptable salt thereof. As shown above, the
compound of formula (VII) can also include the tautomeric
structure:
##STR00126##
or a pharmaceutically acceptable salt thereof.
Compound of Formula (I):
[0163] In some embodiments, the preparation of a compound of
formula (I):
##STR00127##
and pharmaceutically acceptable salts and hydrates thereof is
provided. The compound of formula (I) also includes the tautomeric
structure:
##STR00128##
or a pharmaceutically acceptable salt thereof.
[0164] The synthesis of the compound of formula (I) is preferably
carried out so as to achieve the desired stereochemistry and avoid
oxidation due to pyran ring opening during the chemical
synthesis.
[0165] The compound of formula (I) may be prepared, for example, by
deprotecting the compound of formula (VII):
##STR00129##
wherein each R.sub.1 is independently H or a protecting group, as
defined above, to prepare the compound of formula (I).
[0166] In this synthesis, the deprotection may involve, for
example, either sequential or one-pot deprotection of certain amino
and hydroxyl protecting groups on a compound of formula (VII) to
furnish the compound of formula (I). Suitable reagents and
conditions for the deprotection of a compound of formula (VII) can
be readily determined by those of ordinary skill in the art. For
example, compound (I) may be formed upon treatment of a compound of
formula (VII) under conditions so that hydroxyl protecting groups,
such as acetate, isopropylidine, and benzylidine protecting groups,
are removed from the formula (VII) structure. The acetate group can
be cleaved, for example, under Zemplen conditions using catalytic
NaOMe as a base in methanol. The benzylidene and isopropylidene
groups can be cleaved by hydrogenation or using acidic hydrolysis
as reported by R. M. Hann et al., J. Am. Chem. Soc., 72, 561
(1950). In yet another example, the deprotection can be performed
so that amino protecting groups, such as 9-fluorenylmethyl
carbamate (Fmoc), t-butyl carbamate (Boc), and carboxybenzyl
carbamate (cbz) protecting groups are cleaved from the compound of
formula (VII). 9-fluorenylmethyl carbamate (Fmoc) can be removed
under mild conditions with an amine base (e.g., piperidine) to
afford the free amine and dibenzofulvene, as described by E.
Atherton et al., "The Fluorenylmethoxycarbonyl Amino Protecting
Group," in The Peptides, S. Udenfriend and J. Meienhofer, Academic
Press, New York, 1987, p. 1. t-butyl carbamate (Boc) can be
removed, as reported by G. L. Stahl et al., J. Org. Chem., 43, 2285
(1978), under acidic conditions (e.g., 3 M HCl in EtOAc).
Hydrogenation can be used to cleave the carboxybenzyl carbamate
(cbz) protecting group as described by J. Meienhofer et al.,
Tetrahedron Lett., 29, 2983 (1988).
[0167] To prevent oxidation of formula (I) during the reaction, the
deprotection may be performed under anaerobic conditions. The
deprotection may also be performed at ambient temperature or at
temperatures of from about 20-60.degree. C. (e.g., 25, 30, 35, 40,
45, 50, or 55.degree. C.).
[0168] The compound of formula (I) may be isolated in the form of a
pharmaceutically acceptable salt. For example, the compound of
formula (I) may be crystallized in the presence of HCl to form the
HCl salt form of the compound. In some embodiments, the compound of
formula (I) may be crystallized as the HBr salt form of the
compound. The compound of formula (I) may also be isolated, e.g.,
by precipitation as a sodium salt by treating with NaOH. The
compound of formula (I) is labile under certain reaction and
storage conditions. In some embodiments, the final solution
comprising the compound of formula (I) may be acidified by methods
known in the art. For example, the compound of formula (I), if
stored in solution, can be stored in an acidic solution.
[0169] In some embodiments, the compound of formula (I) may be
prepared, for example, by: reacting a compound of formula
(II-A):
##STR00130##
with a compound of formula (III-A):
##STR00131##
in the presence of a hydrazine to produce a compound of formula
(IV-A):
##STR00132##
selectively protecting the compound of formula (IV-A) to prepare a
compound of formula (V-A):
##STR00133##
wherein: R.sub.1 is a protecting group, as defined above;
phosphorylating the compound of formula (V-A) to prepare a compound
of formula (VI-A):
##STR00134##
oxidizing the compound of formula (VI-A) to prepare a compound of
formula (VII-A):
##STR00135##
and deprotecting the compound of formula (VII-A) to prepare the
compound of formula (I). For example, a compound of formula (I) can
be prepared as shown in Scheme 3.
##STR00136##
[0170] In another embodiment, the compound of formula (I) is
prepared by: reacting a compound of formula (II-A):
##STR00137##
with a compound of formula (III-A):
##STR00138##
in the presence of a hydrazine to produce a compound of formula
(IV-A):
##STR00139##
selectively protecting the compound of formula (IV-A) to prepare a
compound of formula (V-B):
##STR00140##
wherein: each R.sub.1 is independently a protecting group, as
defined above; phosphorylating the compound of formula (V-B) to
prepare a compound of formula (VI-B):
##STR00141##
oxidizing the compound of formula (VI-B) to prepare a compound of
formula (VII-B):
##STR00142##
and deprotecting the compound of formula (VII-B) to prepare the
compound of formula (I). For example, a compound of formula (I) can
be prepared as shown in Scheme 4.
##STR00143##
[0171] Alternatively, a compound of formula (I) can be formed as
shown in Scheme 5. A diaminopyrimidinone compound of formula (II)
can be coupled with a phosphorylated hexose sugar of formula
(VIII), to give a compound of formula (IX). The piperizine ring
nitrogen atoms can be protected to give a compound of formula (X)
which can be oxidized to give a diol of formula (XI). The diol of
formula (XI) can then be deprotected using appropriate conditions
and converted to the compound of formula (I).
##STR00144##
In this embodiment, the phosphate may be introduced at the
beginning of the synthesis to avoid undesirable equilibrium between
the pyrano and furano isomers during subsequent steps of the
synthesis. For example, a compound of formula (I) can be prepared
as shown in Scheme 6.
##STR00145##
[0172] A compound of formula (I) can also be formed as shown in
Scheme 7. A diaminopyrimidinone compound of formula (II) can be
coupled to a compound of formula (III) to afford the piperizine
derivative of formula (IV). The piperizine ring nitrogen atoms of
the compound of formula (IV) can be protected under standard
conditions to give a derivative of formula (V). The formula (V)
structure can be oxidized to afford compounds of formula (XII).
Phosphorylation of a compound of formula (XII) gives a compound of
formula (VII). Global deprotection of the compound of formula (VII)
can afford the compound of formula (I).
##STR00146## ##STR00147##
For example, a compound of formula (I) can be prepared as shown in
Scheme 8.
##STR00148##
[0173] In an alternative embodiment, the compound of formula (I)
can be formed as shown in Scheme 9. A diaminopyrimidinone compound
of formula (II) can be condensed with a 2-carbonyl hexose building
block of formula (XVIII) to produce an imine of formula (XX) with
good regioselectivity. Further activation of a functional group at
the anomeric position (such as an acetate) by a Lewis acid (LA)
(e.g., TMSOTf) will furnish a cyclized compound of formula (XXI).
The newly generated glycosidic bond may be in an equatorial
position. Hydrogenation of a compound of formula (XXI) can produce
a compound of formula (IV). Selective protection of a compound of
formula (IV) gives a compound or formula (V) which is oxidized to
give a compound of formula (XII). A compound of formula (XII) can
then be treated as described herein to furnish the compound of
formula (I).
##STR00149## ##STR00150##
For example, a compound of formula (I) can be prepared as shown in
Scheme 10.
##STR00151##
[0174] Alternatively, the compound of formula (I) can be formed as
shown in Scheme 11. In this synthesis, the cyclization of a
diaminopyrimidinone of formula (II) with a hexose building block
can be carried out in the presence of base. Activation with a Lewis
Acid (LA) affords a cyclic product, which can be deprotected to
form an unprotected ketone. The ketone may be phosphorylated and/or
globally deprotected as described herein to produce the compound of
formula (I) or a compound of formula (XIII).
##STR00152##
For example, a compound of formula (I) can be prepared as shown in
Scheme 12.
##STR00153##
In an alternative embodiment, the compound of formula (I) can be
prepared from a cyclization reaction of compound Z, as shown in
scheme 13.
##STR00154##
In some embodiments, the compound of formula (I) can be prepared as
shown in Scheme 14. A diaminopyrimidinone compound of formula (II)
can be coupled to a compound of formula (XXII) to afford the
piperizine derivative of formula (IV). The piperizine ring nitrogen
atoms of the compound of formula (IV) can be protected under
standard conditions to give a derivative of formula (V). In some
embodiments, the compound of formula (V) can undergo selective
deprotection prior to phosphorylation. For example, one or more of
the hydroxyl moieties can be deprotected prior to phosphorylation.
Phosphorylation of a compound of formula (V) affords a compound of
formula (VI). The formula (VI) structure can be oxidized to prepare
a compound of formula (VII). Global deprotection of the compound of
formula (VII) affords the compound of formula (I).
##STR00155##
For example, a compound of formula (I), or a pharmaceutically
acceptable salt thereof, can be prepared by reacting a compound of
formula (II-A):
##STR00156##
with a compound of formula (XXII-A):
##STR00157##
in the presence of a base to produce a compound of formula
(IV-A):
##STR00158##
The compound of formula (IV-A) can be selectively protected to
prepare a compound of formula (V-C):
##STR00159##
wherein each R.sub.1 is H or a protecting group, as described
herein. The compound of (V-C) can then be phosphorylated to afford
a compound of formula (VI-C):
##STR00160##
The compound of formula (VI-C) can then be oxidized to prepare a
compound of formula (VII-C):
##STR00161##
Finally, the compound of formula (VII-C) is deprotected to prepare
the compound of formula (I). In some embodiments, both nitrogens on
the piperazine ring of compounds (V-C), (VI-C) and (VII-C) may be
bound to R.sub.1.
[0175] Alternatively, the compound of formula (I) can be prepared
as shown in Scheme 15. A compound of formula (XXIII) can undergo
epoxidation to provide a compound of formula (XXIV). The compound
of formula (XXIV) can be coupled to a compound of formula (II) to
prepare a compound of formula (XXV). The compound of formula (XXV)
can undergo a ring closure reaction to afford the piperizine
derivative of formula (IV). The piperizine ring nitrogen atoms of
the compound of formula (IV) can be protected under standard
conditions to give a derivative of formula (V). Phosphorylation of
a compound of formula (V) affords a compound of formula (VI). The
formula (VI) structure can be oxidized to provide a compound of
formula (VII). Global deprotection of the compound of formula (VII)
affords the compound of formula (I).
##STR00162## ##STR00163##
[0176] For example, the compound of formula (I), or a
pharmaceutically acceptable salt thereof, can be prepared by
reacting a compound of formula (XXIII-A):
##STR00164##
wherein each R.sub.1 is independently H or a protecting group and
R.sub.4 is H or a leaving group, to produce a compound of formula
(XXIV):
##STR00165##
Reacting the compound of formula (XXIV) with a compound of formula
(II-A):
##STR00166##
to produce a compound of formula (XXV-A):
##STR00167##
Catalyzing ring formation of the compound of formula (XXV-A) to
produce a compound of formula (IV-D):
##STR00168##
Selectively protecting the compound of formula (IV-D) to prepare a
compound of formula (V-D):
##STR00169##
wherein each R.sub.1 is H or a protecting group. Phosphorylating
the compound of formula (V-D) to prepare a compound of formula
(VI-D):
##STR00170##
Oxidizing the compound of formula (VI-D) to prepare a compound of
formula (VII-D):
##STR00171##
Finally, deprotecting the compound of formula (VII-D) to prepare
the compound of formula (I).
Compounds of Formula (XII):
[0177] In another embodiment, compounds of formula (XII) are
prepared:
##STR00172##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group.
[0178] As indicated, certain amino and/or hydroxyl groups of the
formula (XII) structure may be protected with an R.sub.1 protecting
group. For this purpose, R.sub.1 may include any suitable amino or
hydroxyl functional group chosen by a person skilled in the
chemical arts. For example, amino protecting groups within the
scope of the present disclosure include, but are not limited to,
carbamate, amide, N-alkyl, or N-aryl-derived protecting groups.
Non-limiting examples of hydroxyl protecting groups may include
ether, ester, carbonate, or sulfonate protecting groups. The
R.sub.1 protecting groups may be the same or different.
[0179] In particular, the carbamate protecting group may include,
for example, 9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate
(Boc), carboxybenzyl carbamate (cbz), methyl carbamate, ethyl
carbamate, 9-(2-sulfo)fluorenylmethyl carbamate,
9-(2,7-dibromo)fluorenylmethyl carbamate,
17-tetrabenzo[a,c,g,i]fluorenylmethyl carbamate (Tbfmoc),
2-chloro-3-indenylmethyl carbamate (Climoc),
2,7-di-t-butyl[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methyl
carbamate (DBD-Tmoc), 1,1-dioxobenzo[b]thiophene-2-ylmethyl
carbamate (Bsmoc), 2,2,2-trichloroethyl carbamate (Troc),
2-trimethylsilylethyl carbamate (Teoc), 2-phenylethyl carbamate
(hZ), 1,1-dimethyl-2-haloethyl carbamate,
1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-boc),
1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBoc),
1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc),
N-2-pivaloylamino)-1,1-dimethylethyl carbamate,
2-[(2-nitrophenyl)dithio]-1-phenylethyl carbamate (NpSSPeoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, 1-adamantyl
carbamate (1-Adoc), vinyl carbamate (Voc), 1-isopropylallyl
carbamate (Ipaoc), 4-nitrocinnamyl carbamate (Noc),
3-(3'pyridyl)prop-2-enyl carbamate (Paloc), 8-quinolyl carbamate,
alkyldithio carbamate, p-methoxybenzyl carbamate (Moz),
p-nitrobenzyl carbamate (Pnz), p-bromobenzyl carbamate,
p-chlorobenzyl carbamate, 2,4-dichlorobenzyl carbamate,
4-methylsulfinylbenzyl carbamate (Msz), diphenylmethyl carbamate,
2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,
2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methyl
carbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),
2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonoethyl carbamate
(Peoc), 1,1-dimethyl-2-cyanoethyl carbamate, 2-(4-nitrophenyl)ethyl
carbamate, 4-phenylacetoxybenzyl carbamate (PhAcOZ), and
m-chloro-p-acyloxybenzyl carbamate. In some embodiments, a
carbamate protecting group is chosen from 9-fluorenylmethyl
carbamate (Fmoc), t-butyl carbamate (Boc), and carboxybenzyl
carbamate (cbz) protecting groups.
[0180] The amide protecting group may include, for example,
acetamide, phenylacetamide, 3-phenylpropanamide, pent-4-enamide,
picolinamide, 3-pyridylcarboxamide, benzamide, p-phenylbenzamide,
2-methyl-2-(o-phenylazophenoxy)propanamide), 4-chlorobutanamide,
acetoacetamide, 3-(p-hydroxyphenyl)propanamide), and
(N'-dithiobenzyloxycarbonylamino)acetamide.
[0181] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0182] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0183] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0184] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0185] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0186] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (XII) compounds. For example, preparation
of acetyl derivatives of a compound of formula (XII) can improve
solubility and increase product isolation yield.
[0187] A compound of formula (XII) may be prepared by oxidizing a
compound of formula (V):
##STR00173##
wherein: each R.sub.1 is independently H or a protecting group, as
defined above, to prepare a compound of formula (XII):
##STR00174##
[0188] In this synthesis, a compound of formula (XII) may be
prepared by reacting a compound of formula (V) with any oxidizing
agent proper to selectively form the diol of formula (XII).
Suitable oxidizing agents and conditions can be readily determined
by those of ordinary skill in the art. For example, a compound of
formula (XII) may be formed upon treatment of a compound of formula
(V) with a ruthenium compound, such as RuO.sub.4.sup.-/NMO. Other
oxidants, such as Dess-Martin's reagent, DMSO/triflic anhydride,
TFAA/DMSO, PDC, hydrogen peroxide, inorganic peroxides, nitric
acid, nitrates, chlorite, chlorate, perchlorate, hypochlorite,
peroxide, iodine, ozone, nitrous oxide, silver oxide, permanganate
salts, hexavalent chromium compounds, chromic acid, dichromic
acids, chromium trioxide, pyridinium chlorochromate, persulfuric
acid, sulfoxides, sulfuric acid, Tollens' reagent,
2,2'-dipyridyldisulfide (DPS), and osmium tetroxide may also be
used. In one embodiment, the oxidation conditions are performed so
that the pyrazine ring of compound (XII) is not oxidized. In some
embodiments, the oxidizing agent is chosen from
RuO.sub.4.sup.-/NMO, Dess-Martin's reagent, DMSO/triflic anhydride,
TFAA/DMSO, and PDC.
[0189] For example, the oxidation reaction may be carried out by
treating a compound of formula (V) with RuO.sub.4.sup.-/NMO at
ambient temperature to afford a compound of formula (XII). In
another embodiment, a compound of formula (XII) is formed by
treating a compound of formula (V) with RuO.sub.4.sup.-/NMO at a
temperature from about 20-60.degree. C. (e.g., at about 20, 25, 30,
35, 40, 45, 50, or 55.degree. C.).
[0190] As will be understood, the isomeric form of the formula
(XII) structure may regulate the stereospecificity of subsequent
intermediates in the successive steps in the synthesis of formula
(I) or formula (XIII). Accordingly, a particular isomer may be
isolated at this step of the synthesis or, alternatively, isomeric
mixtures of a compound of formula (XII) may be carried through and
isolated at later stages of the synthesis.
Compounds of Formula (XIII):
[0191] In another embodiment, a compound of the formula (XIII) is
prepared:
##STR00175##
or pharmaceutically acceptable salts or hydrates thereof. A
compound of formula (XIII) also includes the tautomeric
structure:
##STR00176##
or pharmaceutically acceptable salts or hydrates thereof
[0192] The compound of formula (I) can be a reaction product of a
compound of formula (XIII) and water. Alternatively, the compound
of formula (XIII) can be a dehydration product of a compound of
formula (I). Given the equilibrium created between these two
products, at certain pHs and conditions, both species may be
present in an aqueous solution. One of skill in the art can control
synthetic conditions (e.g., working in the absence of water) to
isolate the ketone species of formula (XIII) to reduce or eliminate
the presence of the compound of formula (I). While the methods
described above for producing a compound of formula (I) give rise
to a gem-diol following oxidation (e.g., a compound of formula
(VII)), the methods can include an additional step involving
suitable dehydration conditions (e.g., concentrated acid or base)
to produce a ketone (e.g., a compound of formula (XIV)). For
example, the conversion can occur as shown in Scheme 16.
##STR00177##
Following formation of the ketone, the remaining steps of the
methods described below may be used to produce a compound of
formula (XIII).
[0193] The compound of formula (XIII) may be prepared by
deprotecting the compound of formula (XIV):
##STR00178##
wherein: each R.sub.1 is independently H or a protecting group, as
defined above, to prepare the compound of formula (XIII).
[0194] In this synthesis, the deprotection may involve, for
example, either sequential or one-pot deprotection of certain amino
and hydroxyl protecting groups of formula (XIV) to furnish the
compound of formula (XIII). Suitable reagents and conditions for
the deprotection of the compound of formula (XIV) can be readily
determined by those of ordinary skill in the art. For example,
compound (XIII) may be formed upon treatment of the compound of
formula (XIV) under conditions so that hydroxyl protecting groups,
such as acetate, isopropylidine, and benzylidine protecting groups,
are removed from formula (XIV). The acetate group can be cleaved,
for example, under Zemplen conditions using catalytic NaOMe as a
base in methanol. The benzylidene and isopropylidene groups can be
cleaved by hydrogenation or using acidic hydrolysis as reported by
R. M. Hann et al., J. Am. Chem. Soc., 72, 561 (1950). In yet
another example, the deprotection can be performed so that amino
protecting groups, such as 9-fluorenylmethyl carbamate (Fmoc),
t-butyl carbamate (Boc), and carboxybenzyl carbamate (cbz)
protecting groups are cleaved from the compound of formula (XIV).
9-fluorenylmethyl carbamate (Fmoc) can be removed under mild
conditions with an amine base (e.g., piperidine) to afford the free
amine and dibenzofulvene, as described by E. Atherton et al., "The
Fluorenylmethoxycarbonyl Amino Protecting Group," in The Peptides,
S. Udenfriend and J. Meienhofer, Academic Press, New York, 1987, p.
1. t-butyl carbamate (Boc) can be removed, as reported by G. L.
Stahl et al., J. Org. Chem., 43, 2285 (1978), under acidic
conditions (e.g., 3 M HCl in EtOAc). Hydrogenation can be used to
cleave the carboxybenzyl carbamate (cbz) protecting group as
described by J. Meienhofer et al., Tetrahedron Lett., 29, 2983
(1988).
[0195] To prevent oxidation of formula (XIII) during the reaction,
the deprotection may be performed under anaerobic conditions. The
deprotection may also be performed at ambient temperature or at
temperatures of from 20-60.degree. C., or 25, 30, 35, 40, 45, 50,
or 55.degree. C.
[0196] Alternatively, compounds of formula (XIII) can be formed as
shown in Scheme 17. A diaminopyrimidinone compound of formula (II)
can be coupled with a phosphorylated hexose sugar of formula
(VIII), to give a compound of formula (IX). The piperizine ring
nitrogen atoms can be protected to give a compound of formula (X)
which can be oxidized to give a diol of formula (XV). The diol of
formula (XV) can then be deprotected using appropriate conditions
and converted to the compound of formula (XIII).
##STR00179##
[0197] In another embodiment, a compound of formula (XIII) may be
formed as shown in Scheme 18. For example, a diaminopyrimidinone
compound of formula (II) can be reacted with a protected or
unprotected hexose sugar of formula (III) to give a compound of
formula (IV). The ring nitrogen atoms of the piperizine ring of
formula (IV) can then be selectively protected using standard
conditions to give a derivative of formula (V). Phosphorylation of
the compound of formula (V) can furnish a phosphate intermediate of
formula (VI). The phosphate of formula (VI) can be converted to a
ketone of formula (XIV) under appropriate oxidation conditions.
Finally, the compound of formula (XIV) can be deprotected to give
the compound of formula (XIII).
##STR00180##
[0198] Alternatively, the compound of formula (XIII) can be
prepared as shown in Scheme 19. A diaminopyrimidinone compound of
formula (II) can be coupled to a compound of formula (XXII) to
afford the piperizine derivative of formula (IV). The piperizine
ring nitrogen atoms of the compound of formula (IV) can be
protected under standard conditions to give a derivative of formula
(V). In some embodiments, the compound of formula (V) can undergo
selective deprotection prior to phosphorylation. For example, one
or more of the hydroxyl moieties can be deprotected prior to
phosphorylation. Phosphorylation of a compound of formula (V)
affords compounds of formula (VI). The formula (VI) structure can
be oxidized to afford compounds of formula (XIV). Global
deprotection of the compound of formula (XIV) can afford the
compound of formula (XIII).
##STR00181##
[0199] Alternatively, the compound of formula (XIII) can be
prepared as shown in Scheme 20. A compound of formula (XXIII) can
undergo epoxidation to provide a compound of formula (XXIV). The
compound of formula (XXIV) can be coupled to a compound of formula
(II) to prepare a compound of formula (XXV). The compound of
formula (XXV) can undergo a ring closure reaction to afford the
piperizine derivative of formula (IV). The piperizine ring nitrogen
atoms of the compound of formula (IV) can be protected under
standard conditions to give a derivative of formula (V).
Phosphorylation of a compound of formula (V) affords compounds of
formula (VI). The formula (VI) structure can be oxidized to afford
compounds of formula (XIV). Global deprotection of the compound of
formula (XIV) can afford the compound of formula (XIII).
##STR00182## ##STR00183##
[0200] The compound of formula (XIII) may be isolated in the form a
pharmaceutically acceptable salt. For example, the compound of
formula (XIII) may be crystallized in the presence of HCl to form
the HCl salt form of the compound. In some embodiments, the
compound of formula (XIII) may be crystallized as the HBr salt form
of the compound. The compound of formula (XIII) may also be
isolated, e.g., by precipitation as a sodium salt by treating with
NaOH. The compound of formula (XIII) is labile under certain
reaction and storage conditions. In some embodiments, the final
solution comprising the compound of formula (XIII) may be acidified
by methods known in the art. For example, the compound of formula
(XIII), if stored in solution, can be stored in an acidic
solution.
Compounds of Formula (XIV)
[0201] In another embodiment, compounds of formula (XIV) are
prepared:
##STR00184##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group. For example,
the compound for formula (XIV) includes the compound (XIV-A):
##STR00185##
or a pharmaceutically acceptable salt thereof, wherein R.sub.1 is H
or a protecting group. The compound of formula (XIV) also includes,
for example, the compound:
##STR00186##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (XIV) includes the compound (XIV-B):
##STR00187##
or a pharmaceutically acceptable salt thereof. In some embodiments,
the compound of formula (XIV) includes the compound (XIV-C):
##STR00188##
or a pharmaceutically acceptable salt thereof. In some embodiments,
a compound of formula (XIV) can include one or more of the
following:
##STR00189##
or a pharmaceutically acceptable salt thereof. For example, a
compound of formula (XIV) can include one or more of the
following:
##STR00190##
or a pharmaceutically acceptable salt thereof. In some embodiments,
one or more of the above compounds can be separated by those
skilled in the art by a variety of methods, including high
performance liquid chromatography (HPLC) ("Preparative LC-MS
Purification: Improved Compound Specific Method Optimization" K. F.
Blom, et al., J. Combi. Chem. 6(6), 874 (2004), which is
incorporated herein by reference in its entirety) and normal phase
silica chromatography.
[0202] As indicated, certain amino and/or hydroxyl groups of the
formula (XIV) structure may be protected with an R.sub.1 protecting
group. For this purpose, R.sub.1 may include any suitable amino or
hydroxyl functional group chosen by a person skilled in the
chemical arts. For example, amino protecting groups within the
scope of the present disclosure include, but are not limited to,
carbamate, amide, N-alkyl, or N-aryl-derived protecting groups.
Non-limiting examples of hydroxyl protecting groups may include
ether, ester, carbonate, or sulfonate protecting groups. The
R.sub.1 protecting groups may be the same or different.
[0203] In particular, the carbamate protecting group may include,
for example, 9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate
(Boc), carboxybenzyl carbamate (cbz), methyl carbamate, ethyl
carbamate, 9-(2-sulfo)fluorenylmethyl carbamate,
9-(2,7-dibromo)fluorenylmethyl carbamate,
17-tetrabenzo[a,c,g,i]fluorenylmethyl carbamate (Tbfmoc),
2-chloro-3-indenylmethyl carbamate (Climoc),
2,7-di-t-butyl[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methyl
carbamate (DBD-Tmoc), 1,1-dioxobenzo[b]thiophene-2-ylmethyl
carbamate (Bsmoc), 2,2,2-trichloroethyl carbamate (Troc),
2-trimethylsilylethyl carbamate (Teoc), 2-phenylethyl carbamate
(hZ), 1,1-dimethyl-2-haloethyl carbamate,
1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-boc),
1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBoc),
1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc),
N-2-pivaloylamino)-1,1-dimethylethyl carbamate,
2-[(2-nitrophenyl)dithio]-1-phenylethyl carbamate (NpSSPeoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, 1-adamantyl
carbamate (1-Adoc), vinyl carbamate (Voc), 1-isopropylallyl
carbamate (Ipaoc), 4-nitrocinnamyl carbamate (Noc),
3-(3'pyridyl)prop-2-enyl carbamate (Paloc), 8-quinolyl carbamate,
alkyldithio carbamate, p-methoxybenzyl carbamate (Moz),
p-nitrobenzyl carbamate (Pnz), p-bromobenzyl carbamate,
p-chlorobenzyl carbamate, 2,4-dichlorobenzyl carbamate,
4-methylsulfinylbenzyl carbamate (Msz), diphenylmethyl carbamate,
2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,
2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methyl
carbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),
2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonoethyl carbamate
(Peoc), 1,1-dimethyl-2-cyanoethyl carbamate, 2-(4-nitrophenyl)ethyl
carbamate, 4-phenylacetoxybenzyl carbamate (PhAcOZ), and
m-chloro-p-acyloxybenzyl carbamate. In particular,
9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate (Boc), and
carboxybenzyl carbamate (cbz) protecting groups may be used.
[0204] The amide protecting group may include, for example,
acetamide, phenylacetamide, 3-phenylpropanamide, pent-4-enamide,
picolinamide, 3-pyridylcarboxamide, benzamide, p-phenylbenzamide,
2-methyl-2-(o-phenylazophenoxy)propanamide), 4-chlorobutanamide,
acetoacetamide, 3-(p-hydroxyphenyl)propanamide), and
(N'-dithiobenzyloxycarbonylamino)acetamide.
[0205] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0206] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0207] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0208] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0209] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0210] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (XIV) compounds. For example, preparation
of acetyl derivatives of formula (XIV) can improve solubility and
increase product isolation yield.
[0211] The compound of formula (XIV) may be prepared by oxidizing
the compound of formula (VI):
##STR00191##
to prepare a compound of formula (XIV):
##STR00192##
wherein: each R.sub.1 is independently H or a protecting group, as
defined above.
[0212] In this synthesis, the compound of formula (XIV) may be
prepared by reacting the compound of formula (VI) with any
oxidizing agent proper to selectively form the ketone of formula
(XIV). Suitable oxidizing agents and conditions can be readily
determined by those of ordinary skill in the art. For example,
compound (XIV) may be formed upon treatment of the compound of
formula (VI) with a ruthenium compound, such as
RuO.sub.4.sup.-/NMO. Other oxidants, such as Dess-Martin's reagent,
DMSO/triflic anhydride, TFAA/DMSO, PDC, hydrogen peroxide,
inorganic peroxides, nitric acid, nitrates, chlorite, chlorate,
perchlorate, hypochlorite, peroxide, iodine, ozone, nitrous oxide,
silver oxide, permanganate salts, hexavalent chromium compounds,
chromic acid, dichromic acids, chromium trioxide, pyridinium
chlorochromate, persulfuric acid, sulfoxides, sulfuric acid,
Tollens' reagent, 2,2'-dipyridyldisulfide (DPS), and osmium
tetroxide may also be used. In one embodiment, the oxidation
conditions are performed so that the pyrazine ring of compound
(XIV) is not oxidized. In particular, the oxidizing agents
RuO.sub.4.sup.-/NMO, Dess-Martin's reagent, DMSO/triflic anhydride
and PDC may be used.
[0213] For example, the oxidation reaction may be carried out by
treating the compound of formula (VI) with RuO.sub.4.sup.-/NMO at
ambient temperature to afford the compound of formula (XIV). In
another embodiment, the compound of formula (XIV) is formed by
treating the compound of formula (VI) with RuO.sub.4.sup.-/NMO at a
temperature from 20-60.degree. C., or at 20, 25, 30, 35, 40, 45,
50, or 55.degree. C.
[0214] A compound of formula (XIV) can also be prepared by
dehydrating a compound of formula (VII). Suitable reaction
conditions for such a dehydration reaction are readily determined
by those of ordinary skill in the art. For example, a compound of
formula (VII) can be combined with a concentrated acid or base to
prepare a compound of formula (XIV).
[0215] As will be understood, the isomeric form of the formula
(XIV) structure may regulate the stereospecificity of subsequent
intermediates in the successive steps of the synthesis of formula
(XIII). Accordingly, a particular isomer may be isolated at this
step of the synthesis or, alternatively, isomeric mixtures of
formula (XIV) may be carried through and isolated at later stages
of the synthesis.
[0216] In one embodiment, the compound of formula (XIV) includes
the isomer:
##STR00193##
The compound of formula (XIV) also includes the tautomeric
structure:
##STR00194##
or a pharmaceutically acceptable salt thereof.
Compounds of Formula (XXII)
[0217] Another embodiment relates to a compound of formula
(XXII):
##STR00195##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group.
[0218] As indicated, the hydroxyl groups in the compound of formula
(XXII) may be in protected or unprotected form. For example, in an
unprotected form, the compound for formula (XXII) may include the
compound (XXII-A):
##STR00196##
or a pharmaceutically acceptable salt, thereof
[0219] Certain hydroxyl groups of the formula (XXII) structure may
be protected with an R.sub.1 protecting group. For this purpose,
R.sub.1 may include any suitable hydroxyl functional group chosen
by a person skilled in the chemical arts. For example, non-limiting
examples of hydroxyl protecting groups may include ether, ester,
carbonate, or sulfonate protecting groups. The R.sub.1 protecting
groups may be the same or different.
[0220] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0221] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0222] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0223] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0224] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0225] In some embodiments, two adjacent R.sub.1 groups come
together to form an isopropylidine acetal, benzylidine acetal,
1,5-dioxaspiro[5.5]undecane (cyclohexylidene acetal),
6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, the R.sub.1
groups at the 4- and 5-positions of the hexose ring component of
formula (XXII) can combine to form an isopropylidine acetal,
benzylidine acetal, 1,5-dioxaspiro[5.5]undecane (cyclohexylidene
acetal), 6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety.
[0226] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (XXII) compounds. For example,
preparation of acetyl derivatives of formula (XXII) can improve
solubility and increase product isolation yield.
[0227] A compound of formula (XXII) may be prepared by known
methods (see, e.g., Goswami, S.; Adak, A. K. Tetrahedron Lett.
(2005), 46, 221-224) or purchased commercially.
[0228] As will be understood, the isomeric form of the formula
(XXII) structure may govern the stereospecificity of subsequent
intermediates in the successive steps of the synthesis of formula
(I) or formula (XIII). Accordingly, a particular isomer may be
isolated at this step of the synthesis or, alternatively, isomeric
mixtures of formula (XXII) may be carried through and isolated at
later stages of the synthesis.
[0229] In some embodiments, the compound of formula (XXII) includes
the isomer:
##STR00197##
or pharmaceutically acceptable salts or hydrates thereof.
Compounds of Formula (XXIII)
[0230] Another embodiment relates to a compound of formula
(XXIII):
##STR00198##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group and R.sub.4
is H or a leaving group.
[0231] As indicated, the hydroxyl groups in the compound of formula
(XXIII) may be in protected or unprotected form. For example, in an
unprotected form, the compound for formula (XXIII) may include the
compound
2-(allyloxy)-6-(hydroxymethyl)tetrahydro-2H-pyran-3,4,5-triol:
##STR00199##
or a pharmaceutically acceptable salt, thereof.
[0232] Certain hydroxyl groups of the formula (XXIII) structure may
be protected with an R.sub.1 protecting group. For this purpose,
R.sub.1 may include any suitable hydroxyl functional group chosen
by a person skilled in the chemical arts. For example, non-limiting
examples of hydroxyl protecting groups may include ether, ester,
carbonate, or sulfonate protecting groups. The R.sub.1 protecting
groups may be the same or different.
[0233] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0234] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0235] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0236] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0237] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0238] In some embodiments, two adjacent R.sub.1 groups come
together to form an isopropylidine acetal, benzylidine acetal,
1,5-dioxaspiro[5.5]undecane (cyclohexylidene acetal),
6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, the R.sub.1
groups at the 4- and 5-positions of the hexose ring component of
formula (XXIII) can combine to form an isopropylidine acetal,
benzylidine acetal, 1,5-dioxaspiro[5.5]undecane (cyclohexylidene
acetal), 6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, a compound of
formula (XXIII) can be a compound of formula (XXIII-B):
##STR00200##
or a pharmaceutically acceptable salt thereof. For example, a
compound of (XXIII) can include a compound:
##STR00201##
or a pharmaceutically acceptable salt thereof.
[0239] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (XXIII) compounds. For example,
preparation of acetyl derivatives of formula (XXIII) can improve
solubility and increase product isolation yield.
[0240] As indicated above, R.sub.4 can be a leaving group. For this
purpose, R.sub.4 may include any suitable hydroxyl leaving group
chosen by a person skilled in the chemical arts. For example,
non-limiting examples of hydroxyl protecting groups may include
tosylates, brosylates, nosylates, mesylates, oxoniums, triflates,
nonaflates, and tresylates.
[0241] A compound of formula (XXIII) may be prepared by known
methods or purchased commercially.
[0242] As will be understood, the isomeric form of the formula
(XXIII) structure may govern the stereospecificity of subsequent
intermediates in the successive steps of the synthesis of formula
(I) or formula (XIII). Accordingly, a particular isomer may be
isolated at this step of the synthesis or, alternatively, isomeric
mixtures of formula (XXIII) may be carried through and isolated at
later stages of the synthesis.
[0243] In one embodiment, the compound of formula (XXIII) includes
the isomer:
##STR00202##
or pharmaceutically acceptable salts or hydrates thereof.
Compounds of Formula (XXIV)
[0244] Another embodiment relates to a compound of formula
(XXIV):
##STR00203##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group.
[0245] As indicated, the hydroxyl groups in the compound of formula
(XXIV) may be in protected or unprotected form. For example, in an
unprotected form, the compound for formula (XXIV) may include the
compound
2-(allyloxy)-4-(hydroxymethyl)-3,7-dioxabicyclo[4.1.0]heptan-5-ol:
##STR00204##
or a pharmaceutically acceptable salt thereof
[0246] Certain hydroxyl groups of the formula (XXIV) structure may
be protected with an R.sub.1 protecting group. For this purpose,
R.sub.1 may include any suitable hydroxyl functional group chosen
by a person skilled in the chemical arts. For example, non-limiting
examples of hydroxyl protecting groups may include ether, ester,
carbonate, or sulfonate protecting groups. The R.sub.1 protecting
groups may be the same or different.
[0247] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0248] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0249] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0250] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0251] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0252] In some embodiments, two adjacent R.sub.1 groups come
together to form an isopropylidine acetal, benzylidine acetal,
1,5-dioxaspiro[5.5]undecane (cyclohexylidene acetal),
6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, the R.sub.1
groups at the 4- and 5-positions of the hexose ring component of
formula (XXIV) can combine to form an isopropylidine acetal,
benzylidine acetal, 1,5-dioxaspiro[5.5]undecane (cyclohexylidene
acetal), 6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, a compound of
formula (XXIV) can include a compound:
##STR00205##
or a pharmaceutically acceptable salt thereof.
[0253] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (XXIV) compounds. For example,
preparation of acetyl derivatives of formula (XXIV) can improve
solubility and increase product isolation yield.
[0254] A compound of formula (XXIV) may be prepared by reacting a
compound of formula (XXIII):
##STR00206##
with a base to prepare a compound of formula (XXIV):
##STR00207##
wherein R.sub.1 is independently H or a protecting group, and
R.sub.4 is H or a leaving group, as defined above.
[0255] In this synthesis, a compound of formula (XXIV) may be
prepared by reacting a compound of formula (XXIII) with any base
proper to selectively form the epoxide of formula (XXIV). Suitable
bases and conditions can be readily determined by those of ordinary
skill in the art. For example, a compound of formula (XXIV) may be
formed upon treatment of a compound of formula (XXIII) with a
strong base, such as sodium hydroxide. Other bases, such as
potassium hydroxide, barium hydroxide, cesium hydroxide, strontium
hydroxide, calcium hydroxide, magnesium hydroxide, lithium
hydroxide, rubidium hydroxide, butyl lithium, lithium
diisopropylamide, lithium diethylamide, sodium amide, sodium
hydride, and lithium bis(trimethylsilyl)amide may also be used.
[0256] For example, the reaction may be carried out by treating a
compound of formula (XXIII) with sodium hydroxide in organic
solvent at about 0.degree. C. then warming to room temperature
overnight to afford a compound of formula (XXIV).
[0257] As will be understood, the isomeric form of the formula
(XXIV) structure may govern the stereospecificity of subsequent
intermediates in the successive steps of the synthesis of formula
(I) or formula (XIII). Accordingly, a particular isomer may be
isolated at this step of the synthesis or, alternatively, isomeric
mixtures of formula (XXIV) may be carried through and isolated at
later stages of the synthesis.
[0258] In one embodiment, the compound of formula (XXIV) includes
the isomer:
##STR00208##
or pharmaceutically acceptable salts or hydrates thereof.
Compounds of Formula (XXV)
[0259] Another embodiment relates to a compound of formula
(XXV):
##STR00209##
or pharmaceutically acceptable salts or hydrates thereof, wherein
each R.sub.1 is independently H or a protecting group.
[0260] As indicated, the hydroxyl groups in the compound of formula
(XXV) may be in protected or unprotected form. For example, in
unprotected form, the compound for formula (XXV) may include the
compound
6-(allyloxy)-5-((2,4-diamino-6-hydroxypyrimidin-5-yl)amino)-2-(hydroxymet-
hyl)tetrahydro-2H-pyran-3,4-diol:
##STR00210##
or a pharmaceutically acceptable salt thereof. Alternatively, one
or more of the hydroxyl groups may be protected. For example, the
compound of formula (XXV) may include a compound of formula
(XXV-A):
##STR00211##
such as the compound
6-(allyloxy)-7-((2,4-diamino-6-(benzyloxy)pyrimidin-5-yl)amino)-2-phenylh-
exahydropyrano[3,2-d][1,3]dioxin-8-ol:
##STR00212##
or a pharmaceutically acceptable salt thereof.
[0261] As indicated, certain amino and/or hydroxyl groups of the
formula (XXV) structure may be protected with an R.sub.1 protecting
group. For this purpose, R.sub.1 may include any suitable amino or
hydroxyl functional group chosen by a person skilled in the
chemical arts. For example, amino protecting groups within the
scope of the present disclosure include, but are not limited to,
carbamate, amide, N-alkyl, or N-aryl-derived protecting groups.
Non-limiting examples of hydroxyl protecting groups may include
ether, ester, carbonate, or sulfonate protecting groups. The
R.sub.1 protecting groups may be the same or different.
[0262] In particular, the carbamate protecting group may include,
for example, 9-fluorenylmethyl carbamate (Fmoc), t-butyl carbamate
(Boc), carboxybenzyl carbamate (cbz), methyl carbamate, ethyl
carbamate, 9-(2-sulfo)fluorenylmethyl carbamate,
dibromo)fluorenylmethyl carbamate,
17-tetrabenzo[a,c,g,i]fluorenylmethyl carbamate (Tbfmoc),
2-chloro-3-indenylmethyl carbamate (Climoc),
2,7-di-t-butyl[9-(10,10-dioxo-10,10,10,10-tetrahydrothioxanthyl)]methyl
carbamate (DBD-Tmoc), 1,1-dioxobenzo[b]thiophene-2-ylmethyl
carbamate (Bsmoc), 2,2,2-trichloroethyl carbamate (Troc),
2-trimethylsilylethyl carbamate (Teoc), 2-phenylethyl carbamate
(hZ), 1,1-dimethyl-2-haloethyl carbamate,
1,1-dimethyl-2,2-dibromoethyl carbamate (DB-t-boc),
1,1-dimethyl-2,2,2-trichloroethyl carbamate (TCBoc),
1-methyl-1-(4-biphenylyl)ethyl carbamate (Bpoc),
1-(3,5-di-t-butylphenyl)-1-methylethyl carbamate (t-Bumeoc),
N-2-pivaloylamino)-1,1-dimethylethyl carbamate,
2-[(2-nitrophenyl)dithio]-1-phenylethyl carbamate (NpSSPeoc),
2-(N,N-dicyclohexylcarboxamido)ethyl carbamate, 1-adamantyl
carbamate (1-Adoc), vinyl carbamate (Voc), 1-isopropylallyl
carbamate (Ipaoc), 4-nitrocinnamyl carbamate (Noc),
3-(3'pyridyl)prop-2-enyl carbamate (Paloc), 8-quinolyl carbamate,
alkyldithio carbamate, p-methoxybenzyl carbamate (Moz),
p-nitrobenzyl carbamate (Pnz), p-bromobenzyl carbamate,
p-chlorobenzyl carbamate, 2,4-dichlorobenzyl carbamate,
4-methylsulfinylbenzyl carbamate (Msz), diphenylmethyl carbamate,
2-methylthioethyl carbamate, 2-methylsulfonylethyl carbamate,
2-(p-toluenesulfonyl)ethyl carbamate, [2-(1,3-dithianyl)]methyl
carbamate (Dmoc), 4-methylthiophenyl carbamate (Mtpc),
2,4-dimethylthiophenyl carbamate (Bmpc), 2-phosphonoethyl carbamate
(Peoc), 1,1-dimethyl-2-cyanoethyl carbamate, 2-(4-nitrophenyl)ethyl
carbamate, 4-phenylacetoxybenzyl carbamate (PhAcOZ), and
m-chloro-p-acyloxybenzyl carbamate. In some embodiments, a
carbamate protecting group is chosen from 9-fluorenylmethyl
carbamate (Fmoc), t-butyl carbamate (Boc), and carboxybenzyl
carbamate (cbz) protecting groups.
[0263] The amide protecting group may include, for example,
acetamide, phenylacetamide, 3-phenylpropanamide, pent-4-enamide,
picolinamide, 3-pyridylcarboxamide, benzamide, p-phenylbenzamide,
2-methyl-2-(o-phenylazophenoxy)propanamide), 4-chlorobutanamide,
acetoacetamide, 3-(p-hydroxyphenyl)propanamide), and
(N'-dithiobenzyloxycarbonylamino)acetamide.
[0264] The ether protecting group may include methyl, methoxy
methyl (MOM), benzyloxymethyl (BOM), methoxyethoxymethyl (MEM),
2-(trimethylsilyl)ethoxymethyl (SEM), methylthiomethyl (MTM),
phenylthiomethyl (PTM), azidomethyl, cyanomethyl,
2,2-dichloro-1,1-difluoroethyl, 2-chloroethyl, 2-bromoethyl,
tetrahydropyranyl (THP), 1-ethoxyethyl (EE), phenacyl,
4-bromophenacyl, cyclopropylmethyl, allyl, propargyl, isopropyl,
cyclohexyl, t-butyl, benzyl, 2,6-dimethylbenzyl, 4-methoxybenzyl
(MPM-OAr), o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl,
4-(dimethylamino)carbonylbenzyl, 4-methylsulfinylbenzyl (Msib),
9-anthrylmethyl, 4-picolyl, heptafluoro-p-tolyl,
tetrafluoro-4-pyridyl, trimethylsilyl (TMS), t-butyldimethylsilyl
(TBDMS), t-butyldiphenylsilyl (TBDPS), and triisopropylsilyl (TIPS)
protecting groups.
[0265] The ester protecting group may include acetoxy (OAc), aryl
formate, aryl acetate, aryl levulinate, aryl pivaloate, aryl
benzoate, and aryl 9-fluoroenecarboxylate. In one embodiment, the
ester protecting group is an acetoxy group.
[0266] The carbonate protecting group may include aryl methyl
carbonate, 1-adamantyl carbonate (Adoc-OAr), t-butyl carbonate
(BOC-OAr), 4-methylsulfinylbenzyl carbonate (Msz-OAr),
2,4-dimethylpent-3-yl carbonate (Doc-OAr), aryl
2,2,2-trichloroethyl carbonate, aryl vinyl carbonate, aryl benzyl
carbonate, and aryl carbonate.
[0267] The sulfonate protecting groups may include aryl
methanesulfonate, aryl toluenesulfonate, and aryl
2-formylbenzenesulfonate.
[0268] In some embodiments, the R.sub.1 protecting group is t-butyl
carbamate (Boc).
[0269] In some embodiments, two adjacent R.sub.1 groups come
together to form an isopropylidine acetal, benzylidine acetal,
1,5-dioxaspiro[5.5]undecane (cyclohexylidene acetal),
6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, the R.sub.1
groups at the 4- and 5-positions of the hexose ring component of
formula (XXV) can combine to form an isopropylidine acetal,
benzylidine acetal, 1,5-dioxaspiro[5.5]undecane (cyclohexylidene
acetal), 6,10-dioxaspiro[4.5]decane (cyclopentylidene acetal), or
2-isobutyl-2-methyl-1,3-dioxane moiety. For example, a compound of
formula (XXV) can include a compound:
##STR00213##
or a pharmaceutically acceptable salt thereof.
[0270] Protection of certain amino and hydroxyl groups can improve
solubility of the formula (XXV) compounds. For example, preparation
of acetyl derivatives of formula (XXV) can improve solubility and
increase product isolation yield.
[0271] A compound of formula (XXV) may be prepared by reacting a
compound of formula (XXIV):
##STR00214##
with a compound of formula (II):
##STR00215##
to afford a compound of formula (XXV):
##STR00216##
wherein R.sub.1 is independently H or a protecting group, as
defined above.
[0272] In this synthesis, a compound of formula (XXV) may be
prepared by coupling a compound of formula (XXIV) with a compound
of formula (II) to form the compound of formula (XXV). Suitable
reaction conditions can be readily determined by those of ordinary
skill in the art. For example, a compound of formula (XXV) may be
formed upon treatment of a compound of formula (XXIV) and (II) in
the presence of an oxidant, such as lithium perchlorate. Other
oxidants, such as RuO.sub.4.sup.-/NMO, Dess-Martin's reagent,
DMSO/triflic anhydride, TFAA/DMSO, PDC, hydrogen peroxide,
inorganic peroxides, nitric acid, nitrates, chlorite, chlorate,
perchlorate, hypochlorite, peroxide, iodine, ozone, nitrous oxide,
silver oxide, permanganate salts, hexavalent chromium compounds,
chromic acid, dichromic acids, chromium trioxide, pyridinium
chlorochromate, persulfuric acid, sulfoxides, sulfuric acid,
Tollens' reagent, 2,2'-dipyridyldisulfide (DPS), and osmium
tetroxide may also be used.
[0273] For example, the oxidation reaction may be carried out by
treating a mixture of a compound of formula (XXIV) and (II) with
lithium perchlorate in organic solvent while heating (e.g., at
about 90.degree. C.) to afford a compound of formula (XXV).
[0274] As will be understood, the isomeric form of the formula
(XXV) structure may govern the stereospecificity of subsequent
intermediates in the successive steps of the synthesis of formula
(I) or formula (XIII). Accordingly, a particular isomer may be
isolated at this step of the synthesis or, alternatively, isomeric
mixtures of formula (XXV) may be carried through and isolated at
later stages of the synthesis.
[0275] In one embodiment, the compound of formula (XXV) includes
the isomer:
##STR00217##
or pharmaceutically acceptable salts or hydrates thereof
[0276] The compound of formula (XXV) can then be used to produce a
compound of formula (IV). A compound of formula (IV) may be
prepared by reacting a compound of formula (XXV):
##STR00218##
with 1,3-dimethylbarbituric acid to afford a compound of formula
(IV), wherein each R.sub.1 is independently H or a protecting
group, as defined above.
[0277] In this synthesis, a compound of formula (IV) may be
prepared by reacting a compound of formula (XXV) with
1,3-dimethylbarbituric acid in the presence of a catalyst to form
the compound of formula (IV). Suitable catalysts and reaction
conditions can be readily determined by those of ordinary skill in
the art. For example, a compound of formula (XXV) may be formed
upon treatment of a compound of formula (XXIV) and (II) in the
presence of a catalyst, such as
tetrakis(triphenylphosphine)palladium(0). Other catalysts may also
be used.
Pharmaceutical Formulations and Dosage Forms
[0278] When employed as pharmaceuticals, the compounds provided
herein can be administered in the form of pharmaceutical
compositions. These compositions can be prepared in a manner well
known in the pharmaceutical art, and can be administered by a
variety of routes, depending upon whether local or systemic
treatment is desired and upon the area to be treated.
Administration may be topical (including transdermal, epidermal,
ophthalmic and to mucous membranes including intranasal, vaginal
and rectal delivery), pulmonary (e.g., by inhalation or
insufflation of powders or aerosols, including by nebulizer;
intratracheal or intranasal), oral or parenteral. Parenteral
administration includes intravenous, intraarterial, subcutaneous,
intraperitoneal, intramuscular or injection or infusion; or
intracranial, e.g., intrathecal or intraventricular,
administration. Parenteral administration can be in the form of a
single bolus dose, or may be, for example, by a continuous
perfusion pump. Pharmaceutical compositions and formulations for
topical administration may include transdermal patches, ointments,
lotions, creams, gels, drops, suppositories, sprays, liquids and
powders. Conventional pharmaceutical carriers, aqueous, powder or
oily bases, thickeners and the like may be necessary or
desirable.
[0279] This disclosure also provides pharmaceutical compositions
which contain, as the active ingredient, a compound provided herein
or a pharmaceutically acceptable salt thereof, in combination with
one or more pharmaceutically acceptable carriers (excipients). In
some embodiments, the composition is suitable for topical
administration. In making the compositions provided herein, the
active ingredient is typically mixed with an excipient, diluted by
an excipient or enclosed within such a carrier in the form of, for
example, a capsule, sachet, paper, or other container. When the
excipient serves as a diluent, it can be a solid, semi-solid, or
liquid material, which acts as a vehicle, carrier or medium for the
active ingredient. Thus, the compositions can be in the form of
tablets, pills, powders, lozenges, sachets, cachets, elixirs,
suspensions, emulsions, solutions, syrups, aerosols (as a solid or
in a liquid medium), ointments containing, for example, up to 10%
by weight of the active compound, soft and hard gelatin capsules,
suppositories, sterile injectable solutions, and sterile packaged
powders.
[0280] In preparing a formulation, an active compound can be milled
to provide the appropriate particle size prior to combining with
the other ingredients. If an active compound is substantially
insoluble, it can be milled to a particle size of less than 200
mesh. If an active compound is substantially water soluble, the
particle size can be adjusted by milling to provide a substantially
uniform distribution in the formulation, e.g. about 40 mesh.
[0281] The compounds provided herein may be milled using known
milling procedures such as wet milling to obtain a particle size
appropriate for tablet formation and for other formulation types.
Finely divided (nanoparticulate) preparations of the compounds
provided herein can be prepared by processes known in the art,
e.g., see International App. No. WO 2002/000196.
[0282] Some examples of suitable excipients include lactose,
dextrose, sucrose, sorbitol, mannitol, starches, gum acacia,
calcium phosphate, alginates, tragacanth, gelatin, calcium
silicate, microcrystalline cellulose, polyvinylpyrrolidone,
cellulose, water, syrup, and methyl cellulose. The formulations can
additionally include: lubricating agents such as talc, magnesium
stearate, and mineral oil; wetting agents; emulsifying and
suspending agents; preserving agents such as methyl- and
propylhydroxy-benzoates; sweetening agents; and flavoring agents.
The compositions provided herein can be formulated so as to provide
quick, sustained or delayed release of the active ingredient after
administration to the patient by employing procedures known in the
art.
[0283] For preparing solid compositions such as tablets, the
principal active ingredient is mixed with a pharmaceutical
excipient to form a solid preformulation composition containing a
homogeneous mixture of a compound provided herein. When referring
to these preformulation compositions as homogeneous, the active
ingredient is typically dispersed evenly throughout the composition
so that the composition can be readily subdivided into equally
effective unit dosage forms such as tablets, pills and capsules.
This solid preformulation is then subdivided into unit dosage forms
of the type described above containing from, for example, about 0.1
to about 1000 mg of the active ingredient provided herein.
[0284] The tablets or pills provided herein can be coated or
otherwise compounded to provide a dosage farm affording the
advantage of prolonged action. For example, the tablet or pill can
comprise an inner dosage and an outer dosage component, the latter
being in the form of an envelope over the former. The two
components can be separated by an enteric layer which serves to
resist disintegration in the stomach and permit the inner component
to pass intact into the duodenum or to be delayed in release. A
variety of materials can be used for such enteric layers or
coatings, such materials including a number of polymeric acids and
mixtures of polymeric acids with such materials as shellac, cetyl
alcohol, and cellulose acetate.
[0285] The liquid forms in which the compounds and compositions
provided herein can be incorporated for administration orally or by
injection include aqueous solutions, suitably flavored syrups,
aqueous or oil suspensions, and flavored emulsions with edible oils
such as cottonseed oil, sesame oil, coconut oil, or peanut oil, as
well as elixirs and similar pharmaceutical vehicles.
[0286] In some embodiments, the compounds provided herein are
formulated for intravenous administration. Pharmaceutical
compositions suitable for injectable use can include sterile
aqueous solutions (where water soluble) or dispersions and sterile
powders for the extemporaneous preparation of sterile injectable
solutions or dispersion. For intravenous administration, suitable
carriers include physiological saline, bacteriostatic water,
Cremophor EL.TM. (BASF, Parsippany, N.J.) or phosphate buffered
saline (PBS). In all cases, the composition must be sterile and
should be fluid to the extent that easy syringability exists. It
should 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 (for example, glycerol, propylene glycol, and
liquid polyethylene glycol, and the like), and suitable mixtures
thereof. The proper fluidity can be maintained, for example, by the
use of a coating such as lecithin, by the maintenance of the
required particle size in the case of dispersion and by the use of
surfactants. Prevention of the action of microorganisms can be
achieved by various antibacterial and antifungal agents, for
example, parabens, chlorobutanol, phenol, ascorbic acid,
thimerosal, and the like. In many cases, it will be preferable to
include isotonic agents, for example, sugars, polyalcohols such as
mannitol, sorbitol, sodium chloride in the composition. Prolonged
absorption of the injectable compositions can be brought about by
including in the composition an agent that delays absorption, for
example, aluminum monostearate and gelatin.
[0287] Sterile injectable solutions can be prepared by
incorporating the active compound in the required amount in an
appropriate solvent with one or a combination of ingredients
enumerated above, as required, followed by filter sterilization.
Generally, dispersions are prepared by incorporating the active
compound into a sterile vehicle, which contains a basic dispersion
medium and the required other ingredients from those enumerated
above. In the case of sterile powders for the preparation of
sterile injectable solutions, the preferred methods of preparation
are vacuum drying and freeze-drying, which yield a powder of the
active ingredient plus any additional desired ingredient from a
previously sterile-filtered solution thereof.
[0288] Compositions for inhalation or insufflation include
solutions and suspensions in pharmaceutically acceptable, aqueous
or organic solvents, or mixtures thereof, and powders. The liquid
or solid compositions may contain suitable pharmaceutically
acceptable excipients as described supra. In some embodiments, the
compositions are administered by the oral or nasal respiratory
route for local or systemic effect. Compositions can be nebulized
by use of inert gases. Nebulized solutions may be breathed directly
from the nebulizing device or the nebulizing device can be attached
to a face mask, tent, or intermittent positive pressure breathing
machine. Solution, suspension, or powder compositions can be
administered orally or nasally from devices which deliver the
formulation in an appropriate manner.
[0289] Topical formulations can contain one or more conventional
carriers. In some embodiments, ointments can contain water and one
or more hydrophobic carriers selected from, for example, liquid
paraffin, polyoxyethylene alkyl ether, propylene glycol, white
Vaseline, and the like. Carrier compositions of creams can be based
on water in combination with glycerol and one or more other
components, e.g. glycerinemonostearate, PEG-glycerinemonostearate
and cetylstearyl alcohol. Gels can be formulated using isopropyl
alcohol and water, suitably in combination with other components
such as, for example, glycerol, hydroxyethyl cellulose, and the
like. In some embodiments, topical formulations contain at least
about 0.1, at least about 0.25, at least about 0.5, at least about
1, at least about 2, or at least about 5 wt % of the compound
provided herein. The topical formulations can be suitably packaged
in tubes of, for example, 100 g which are optionally associated
with instructions for the treatment of the select indication.
[0290] In one embodiment, the compounds provided herein are
prepared with carriers that will protect the compounds against
rapid elimination from the body, such as a controlled release
formulation, including implants and microencapsulated delivery
systems. Biodegradable, biocompatible polymers can be used, such as
ethylene vinyl acetate, polyanhydrides, polyglycolic acid,
collagen, polyorthoesters, and polylactic acid. Such formulations
can be prepared using standard techniques, or obtained
commercially, e.g., from Alza Corporation and Nova Pharmaceuticals,
Inc. Liposomal suspensions (including liposomes targeted to
selected cells with monoclonal antibodies to cellular antigens) can
also be used as pharmaceutically acceptable carriers. These can be
prepared according to methods known to those skilled in the art,
for example, as described in U.S. Pat. No. 4,522,811.
[0291] The compositions administered to a patient can be in the
form of pharmaceutical compositions described above. These
compositions can be sterilized by conventional sterilization
techniques, or may be sterile filtered. Aqueous solutions can be
packaged for use as is, or lyophilized, the lyophilized preparation
being combined with a sterile aqueous carrier prior to
administration. The pH of the compound preparations typically will
be between 3 and 11, more preferably from 5 to 9 and most
preferably from 7 to 8. It will be understood that use of certain
of the foregoing excipients, carriers, or stabilizers will result
in the formation of pharmaceutical salts.
[0292] The compositions can be formulated in a unit dosage form,
each dosage containing from about 5 to about 1000 mg (1 g), more
usually about 100 to about 500 mg, of the active ingredient. The
term "unit dosage forms"" refers to physically discrete units
suitable as unitary dosages for human subjects and other mammals,
each unit containing a predetermined quantity of active material
calculated to produce the desired therapeutic effect, in
association with a suitable pharmaceutical excipient.
[0293] In some embodiments, the compositions provided herein
contain from about 5 to about 50 mg of the active ingredient. One
having ordinary skill in the art will appreciate that this embodies
compositions containing about 5 to about 10, about 10 to about 15,
about 15 to about 20, about 20 to about 25, about 25 to about 30,
about 30 to about 35, about 35 to about 40, about 40 to about 45,
or about 45 to about 50 mg of the active ingredient.
[0294] In some embodiments, the compositions provided herein
contain from about 50 to about 500 mg of the active ingredient. One
having ordinary skill in the art will appreciate that this embodies
compositions containing about 50 to about 100, about 100 to about
150, about 150 to about 200, about 200 to about 250, about 250 to
about 300, about 350 to about 400, or about 450 to about 500 mg of
the active ingredient.
[0295] In some embodiments, the compositions provided herein
contain from about 500 to about 1000 mg of the active ingredient.
One having ordinary skill in the art will appreciate that this
embodies compositions containing about 500 to about 550, about 550
to about 600, about 600 to about 650, about 650 to about 700, about
700 to about 750, about 750 to about 800, about 800 to about 850,
about 850 to about 900, about 900 to about 950, or about 950 to
about 1000 mg of the active ingredient.
[0296] Similar dosages may be used of the compounds described
herein in the methods and uses provided herein.
[0297] The active compound can be effective over a wide dosage
range and is generally administered in a pharmaceutically effective
amount. It will be understood, however, that the amount of the
compound actually administered will usually be determined by a
physician, according to the relevant circumstances, including the
condition to be treated, the chosen route of administration, the
actual compound administered, the age, weight, and response of the
individual patient, the severity of the patient's symptoms, and the
like.
[0298] The amount of compound or composition administered to a
patient will vary depending upon what is being administered, the
purpose of the administration, such as prophylaxis or therapy, the
state of the patient, the manner of administration, and the like.
In therapeutic applications, compositions can be administered to a
patient already suffering from a disease in an amount sufficient to
cure or at least partially arrest the symptoms of the disease and
its complications. Effective doses will depend on the disease
condition being treated as well as by the judgment of the attending
clinician depending upon factors such as the severity of the
disease, the age, weight and general condition of the patient, and
the like.
[0299] The therapeutic dosage of a compound provided herein can
vary according to, for example, the particular use for which the
treatment is made, the manner of administration of the compound,
the health and condition of the patient, and the judgment of the
prescribing physician. The proportion or concentration of a
compound provided herein in a pharmaceutical composition can vary
depending upon a number of factors including dosage, chemical
characteristics (e.g., hydrophobicity), and the route of
administration. For example, the compounds provided herein can be
provided in an aqueous physiological buffer solution containing
about 0.1 to about 10% w/v of the compound for parenteral
administration. Some typical dose ranges are from about 1 mg/kg to
about 1 g/kg of body weight per day. In some embodiments, the dose
range is from about 0.01 mg/kg to about 100 mg/kg of body weight
per day. The dosage is likely to depend on such variables as the
type and extent of progression of the disease or disorder, the
overall health status of the particular patient, the relative
biological efficacy of the compound selected, formulation of the
excipient, and its route of administration. Effective doses can be
extrapolated from dose-response curves derived from in vitro or
animal model test systems.
Examples
Example 1
Preparation of Precursor Z (cPMP)
##STR00219## ##STR00220##
[0300] Experimental.
[0301] Air sensitive reactions were performed under argon. Organic
solutions were dried over anhydrous MgSO.sub.4 and the solvents
were evaporated under reduced pressure Anhydrous and chromatography
solvents were obtained commercially (anhydrous grade solvent from
Sigma-Aldrich Fine Chemicals) and used without any further
purification. Thin layer chromatography (t.l.c.) was performed on
glass or aluminum sheets coated with 60 F.sub.254 silica gel.
Organic compounds were visualized under UV light or with use of a
dip of ammonium molybdate (5 wt %) and cerium(IV) sulfate.4H.sub.2O
(0.2 wt %) in aq. H.sub.2SO.sub.4 (2M), one of I.sub.2 (0.2%) and
KI (7%) in H.sub.2SO.sub.4 (1M), or 0.1% ninhydrin in EtOH.
Chromatography (flash column) was performed on silica gel (40-63
.mu.m) or on an automated system with continuous gradient facility.
Optical rotations were recorded at a path length of 1 dm and are in
units of 10.sup.-1 deg cm.sup.2 g.sup.-1; concentrations are in
g/100 mL .sup.1H NMR spectra were measured in CDCl.sub.3,
CD.sub.3OD (internal Me.sub.4Si, .delta. 0 ppm) or D.sub.2O (HOD,
.delta. 4.79 ppm), and .sup.13C NMR spectra in CDCl.sub.3 (center
line, .delta. 77.0 ppm), CD.sub.3OD (center line, .delta. 49.0 ppm)
or DMSO d.sub.6 (center line .delta. 39.7 ppm), D.sub.2O (no
internal reference or internal CH.sub.3CN, .delta. 1.47 ppm where
stated). Assignments of .sup.1H and .sup.13C resonances were based
on 2D (.sup.1H-.sup.1H DQF-COSY, .sup.1H-.sup.13C HSQC, HMBC) and
DEPT experiments. .sup.31P NMR were run at 202.3 MHz and are
reported without reference. High resolution electrospray mass
spectra (ESI-HRMS) were recorded on a Q-TOF Tandem Mass
Spectrometer. Microanalyses were performed by the Campbell
Microanalytical Department, University of Otago, Dunedin, New
Zealand.
A. Preparation of
(5aS,6R,7R,8R,9aR)-2-amino-6,7-dihydroxy-8-(hydroxymethyl)-3H,4H,5H,5aH,6-
H,7H,8H,9aH,10H-pyrano[3,2-g]pteridin-4-one mono hydrate (1)
[0302] 2,5,6-Triamino-3,4-dihydropyrimidin-4-one dihydrochloride
(Pfleiderer, W.; Chem. Ber. 1957, 90, 2272; Org. Synth. 1952, 32,
45; Org Synth. 1963, Coll. Vol. 4, 245, 10.0 g, 46.7 mmol),
D-galactose phenylhydrazone (Goswami, S.; Adak, A. K. Tetrahedron
Lett. 2005, 46, 221-224, 15.78 g, 58.4 mmol) and 2-mercaptoethanol
(1 mL) were stirred and heated to reflux (bath temp 110.degree. C.)
in a 1:1 mixture of MeOH--H.sub.2O (400 mL) for 2 h. After cooling
to ambient temperature, diethyl ether (500 mL) was added, the flask
was shaken and the diethyl ether layer decanted off and discarded.
The process was repeated with two further portions of diethyl ether
(500 mL) and then the remaining volatiles were evaporated. Methanol
(40 mL), H.sub.2O (40 mL) and triethylamine (39.4 mL, 280 mmol)
were successively added and the mixture seeded with a few
milligrams of 1. After 5 min a yellow solid was filtered off,
washed with a little MeOH and dried to give 1 as a monohydrate
(5.05 g, 36%) of suitable purity for further use. An analytical
portion was recrystallized from DMSO-EtOH or boiling H.sub.2O. MPt
226 dec. [.alpha.].sub.D.sup.20 +135.6 (c1.13, DMSO). .sup.1H NMR
(DMSO d.sub.6): .delta. 10.19 (bs, exchanged D.sub.2O, 1H), 7.29
(d, J=5.0 Hz, slowly exchanged D.sub.2O, 1H), 5.90 (s, exchanged
D.sub.2O, 2H), 5.33 (d, J=5.4 Hz, exchanged D.sub.2O, 1H), 4.66
(ddd, J.about.5.0, .about.1.3, .about.1.3 Hz, 1H), 4.59 (t, J=5.6
Hz, exchanged D.sub.2O, 1H), 4.39 (d, J=10.3 Hz, exchanged
D.sub.2O, 1H), 3.80 (bt, J.about.1.8 Hz, exchanged D.sub.2O, 1H),
3.70 (m, 1H), 3.58 (dd, J=10.3, 3.0 Hz, 1H), 3.53 (dt, J=10.7, 6.4
Hz, 1H), 3.43 (ddd, J=11.2, 5.9, 5.9 Hz, 1H), 3.35 (t, J=6.4 Hz,
1H), 3.04 (br m, 1H). .sup.13C NMR (DMSO d.sub.6 center line
.delta. 39.7): .delta. 156.3 (C), 150.4 (C), 148.4 (C), 99.0 (C),
79.4 (CH), 76.5 (CH), 68.9 (CH), 68.6 (CH), 60.6 (CH.sub.2), 53.9
(CH). Anal. calcd. for C.sub.10H.sub.15N.sub.5O.sub.5.H.sub.2O
39.60C, 5.65H, 23.09N. found 39.64C, 5.71H, 22.83N.
B. Preparation of Compounds 2 (a or b) and 3 (a, b or c)
[0303] Di-tert-butyl dicarbonate (10.33 g, 47.3 mmol) and DMAP
(0.321 g, 2.63 mmol) were added to a stirred suspension of 1 (1.5
g, 5.26 mmol) in anhydrous THF (90 mL) at 50.degree. C. under Ar.
After 20 h a clear solution resulted. The solvent was evaporated
and the residue chromatographed on silica gel (gradient of 0 to 40%
EtOAc in hexanes) to give two product fractions. The first product
to elute was a yellow foam (1.46 g). The product was observed to be
a mixture of two compounds by .sup.1H NMR containing mainly a
product with seven Boc groups (2a or 2b). A sample was crystallized
from EtOAc-hexanes to give 2a or 2b as a fine crystalline solid.
MPt 189-191.degree. C. [.alpha.].sub.D.sup.20 -43.6 (c 0.99, MeOH).
.sup.1H NMR (500 MHz, CDCl.sub.3): .delta. 5.71 (t, J=1.7 Hz, 1H),
5.15 (dt, J=3.5, .about.1.0, 1H), 4.97 (t, J=3.8, 1H), 4.35 (br t,
J=-1.7, 1H), 4.09-3.97 (m, 3H), 3.91 (m, 1H), 1.55, 1.52, 1.51,
1.50, 1.45 (5s, 45H), 1.40 (s, 18H). .sup.13C NMR (125.7 MHz,
CDCl.sub.3): .delta. 152.84 (C), 152.78 (C), 151.5 (C), 150.9 (C),
150.7 (2.times.C), 150.3 (C), 149.1 (C), 144.8 (C), 144.7 (C),
118.0 (C), 84.6 (C), 83.6 (C), 83.5 (C), 82.7 (3.times.C), 82.6
(C), 76.3 (CH), 73.0 (CH), 71.4 (CH), 67.2 (CH), 64.0 (CH.sub.2),
51.4 (CH), 28.1 (CH.sub.3), 27.8 (2.times.CH.sub.3), 27.7
(CH.sub.3), 27.6 (3.times.CH.sub.3). MS-ESI+ for
C.sub.45H.sub.72N.sub.5O.sub.19.sup.+, (M+H).sup.+. Calcd.
986.4817. found 986.4818. Anal. calcd. for
C.sub.45H.sub.71N.sub.5O.sub.19 H.sub.2O 54.39C, 7.39H, 6.34N.
found 54.66C, 7.17H, 7.05N. A second fraction was obtained as a
yellow foam (2.68 g) which by .sup.1H NMR was a product with six
Boc groups present (3a, 3b or 3c). A small amount was crystallized
from EtOAc-hexanes to give colorless crystals.
[.alpha.].sub.D.sup.20 -47.6 (c, 1.17, CHCl.sub.3). .sup.1H NMR
(500 MHz, CDCl.sub.3): .delta. 11.10 (br s, exchanged D.sub.2O,
1H), 5.58 (t, J=1.8 Hz, 1H), 5.17 (d, J=3.4 Hz, 1H), 4.97 (t, J=3.9
Hz, 1H), 4.62 (s, exchanged D.sub.2O, 1H), 4.16 (dd, J=11.3, 5.9
Hz, 1H), 4.12 (dd, J=11.3, 6.4 Hz, 1H), 3.95 (dt, J=6.1, 1.1 Hz,
1H), 3.76 (m, 1H), 1.51, 1.50, 1.49, 1.48, 1.46 (5s, 54H). .sup.13C
NMR (125.7 MHz, CDCl.sub.3): .delta. 156.6 (C), 153.0 (C), 152.9
(C), 151.9 (C), 150.6 (C), 149.4 (2.times.C), 136.2 (C), 131.8 (C),
116.9 (C), 85.0 (2.times.C), 83.3 (C), 82.8 (C), 82.49 (C), 82.46
(C), 73.3 (CH), 71.5 (CH), 67.2 (CH), 64.5 (CH.sub.2), 51.3 (CH),
28.0, 27.72, 27.68, 27.6 (4.times.CH.sub.3). MS-ESI+ for
C.sub.40H.sub.64N.sub.5O.sub.17.sup.+, (M+H).sup.+ calcd. 886.4287.
found 886.4289.
C. Preparation of Compound 4a, 4b or 4c
[0304] Step 1
[0305] The first fraction from B above containing mainly compounds
2a or 2b (1.46 g, 1.481 mmol) was dissolved in MeOH (29 mL) and
sodium methoxide in MeOH (1M, 8.14 mL, 8.14 mmol) added. After
leaving at ambient temperature for 20 h the solution was
neutralized with Dowex 50WX8 (H.sup.+) resin then the solids
filtered off and the solvent evaporated.
[0306] Step 2
[0307] The second fraction from B above containing mainly 3a, 3b or
3c (2.68 g, 3.02 mmol) was dissolved in MeOH (54 mL) and sodium
methoxide in MeOH (1M, 12.10 mL, 12.10 mmol) added. After leaving
at ambient temperature for 20 h the solution was neutralized with
Dowex 50WX8 (H.sup.+) resin then the solids filtered off and the
solvent evaporated.
[0308] The products from step 1 and step 2 above were combined and
chromatographed on silica gel (gradient of 0 to 15% MeOH in
CHCl.sub.3) to give 4a, 4b or 4c as a cream colored solid (1.97 g).
.sup.1H NMR (500 MHz, DMSO d.sub.6): .delta. 12.67 (br s, exchanged
D.sub.2O, 1H), 5.48 (d, J=5.2 Hz, exchanged D.sub.2O, 1H), 5.43 (t,
J=.about.1.9 Hz, after D.sub.2O exchange became a d, J=1.9 Hz, 1H),
5.00 (br s, exchanged D.sub.2O, 1H), 4.62 (d, J=5.7 Hz, exchanged
D.sub.2O, 1H), 4.27 (d, J=6.0 Hz, exchanged D.sub.2O, 1H), 3.89
(dt, J=5.2, 3.8 Hz, after D.sub.2O became a t, J=3.9 Hz, 1H), 3.62
(dd, J=6.0, 3.7 Hz, after D.sub.2O exchange became a d, J=3.7 Hz,
1H), 3.52-3.39 (m, 4H), 1.42 (s, 9H), 1.41 (s, 18H). .sup.13C NMR
(125.7 MHz, DMSO d.sub.6): .delta. 157.9 (C), 151.1, (C), 149.8
(2.times.C), 134.6 (C), 131.4 (C), 118.8 (C), 83.5 (2.times.C),
81.3 (C), 78.2 (CH), 76.5 (CH), 68.1 (CH), 66.8 (CH), 60.6
(CH.sub.2), 54.4 (CH), 27.9 (CH.sub.3), 27.6 (2.times.CH.sub.3).
MS-ESI+ for C.sub.25H.sub.40N.sub.5O.sub.11.sup.+, (M+H).sup.+
calcd. 586.2719. found 586.2717.
D. Preparation of Compound 5a, 5b or 5c
[0309] Compound 4a, 4b or 4c (992 mg, 1.69 mmol) was dissolved in
anhydrous pyridine and concentrated. The residue was dissolved in
anhydrous CH.sub.2Cl.sub.2 (10 mL) and pyridine (5 mL) under a
nitrogen atmosphere and the solution was cooled to -42.degree. C.
in an acetonitrile/dry ice bath. Methyl dichlorophosphate (187
.mu.L, 1.86 mmol) was added dropwise and the mixture was stirred
for 2 h 20 min. Water (10 mL) was added to the cold solution which
was then removed from the cold bath and diluted with ethyl acetate
(50 mL) and saturated NaCl solution (30 mL) The organic portion was
separated and washed with saturated NaCl solution. The combined
aqueous portions were extracted twice further with ethyl acetate
and the combined organic portions were dried over MgSO.sub.4 and
concentrated. Purification by silica gel flash column
chromatography (eluting with 2-20% methanol in ethyl acetate) gave
the cyclic methyl phosphate 5a, 5b or 5c (731 mg, 65%). .sup.1H NMR
(500 MHz, CDCl.sub.3,): .delta. 11.72 (bs, exchanged D.sub.2O, 1H),
5.63 (t, J=1.8 Hz, 1H), 5.41 (s, exchanged D.sub.2O, 1H), 4.95 (d,
J=3.2 Hz, 1H), 4.70 (dt, J=12.4, 1.8 Hz, 1H), 4.42 (dd, J=22.1,
12.1 Hz, 1H). 4.15 (q, J=3.7 Hz, 1H), 3.82 (s, 1H), 3.75 (s, 1H),
3.58 (d, J=11.7 Hz, 3H), 2.10 (bs, exchanged D.sub.2O,
1H+H.sub.2O), 1.50 (s, 9H), 1.46 (s, 18H). .sup.13C NMR (125.7 MHz,
CDCl.sub.3, centre line .delta. 77.0): .delta. 157.5 (C), 151.2
(C), 149.6 (2.times.C), 134.5 (C), 132.3 (C), 117.6 (C), 84.7
(2.times.C), 82.8 (C), 77.3 (CH), 74.8 (d, J=4.1 Hz, CH), 69.7
(CH.sub.2), 68.8 (d, J=4.1 Hz, CH), 68.6 (d, J=5.9 Hz, CH), 56.0
(d, J=7.4 Hz, CH.sub.3), 51.8 (CH), 28.1 (CH.sub.3), 27.8
(CH.sub.3). MS-ESI+ for C.sub.26H.sub.40N.sub.5NaO.sub.13P.sup.+
(M+Na).sup.+, calcd. 684.2252. found 684.2251.
E. Preparation of Compound 6a, 6b or 6c
[0310] Compound 5a, 5b or 5c (223 mg, 0.34 mmol) was dissolved in
anhydrous CH.sub.2Cl.sub.2 (7 mL) under a nitrogen atmosphere.
Anhydrous DMSO (104 .mu.L, 1.46 mmol) was added and the solution
was cooled to -78.degree. C. Trifluoroacetic anhydride (104 .mu.L,
0.74 mmol) was added dropwise and the mixture was stirred for 40
min. N,N-diisopropylethylamine (513 .mu.L, 2.94 mmol) was added and
the stirring was continued for 50 min at -78.degree. C. Saturated
NaCl solution (20 mL) was added and the mixture removed from the
cold bath and diluted with CH.sub.2Cl.sub.2 (30 mL). Glacial acetic
acid (170 .mu.L, 8.75 mmol) was added and the mixture was stirred
for 10 min. The layers were separated and the aqueous phase was
washed with CH.sub.2Cl.sub.2 (10 mL) The combined organic phases
were washed with 5% aqueous HCl, 3:1 saturated NaCl solution: 10%
NaHCO.sub.3 solution and saturated NaCl solution successively,
dried over MgSO.sub.4, and concentrated to give compound 6a, 6b or
6c (228 mg, quant.) of suitable purity for further use. .sup.1H NMR
(500 MHz, CDCl.sub.3): .delta. 5.86 (m, 1H), 5.07 (m, 1H),
4.70-4.64 (m, 2H), 4.49-4.40 (m, 1H), 4.27 (m, 1H), 3.56, m, 4H),
1.49 (s, 9H), 1.46 (s, 18H) ppm. .sup.13C NMR (500 MHz,
CDCl.sub.3): .delta. 157.5 (C), 151.1 (C), 150.6 (2C), 134.6 (C),
132.7 (C), 116.6 (C), 92.0 (C), 84.6 (2C), 83.6 (C), 78.0 (CH),
76.0 (CH), 70.4 (CH.sub.2), 67.9 (CH), 56.2 (CH.sub.3) 56.0 (CH),
28.2 (3 CH.sub.3), 26.8 (6 CH.sub.3) ppm. .sup.31P NMR (500 MHz,
CDCl.sub.3): .delta.-6.3 ppm.
F. Preparation of Compound 7:
(4aR,5aR,11aR,12aS)-1,3,2-Dioxaphosphorino[4',5':5,6]pyrano[3,2-g]pteridi-
n-10(4H)-one,8-amino-4a,5a,6,9,11,11a,12,12a-octahydro-2,12,12-trihydroxy--
2-oxide
[0311] Compound 6a, 6b or 6c (10 mg, 14.8 .mu.mol) was dissolved in
dry acetonitrile (0.2 mL) and cooled to 0.degree. C.
Bromotrimethylsilane (19.2 .mu.l, 148 .mu.mol) was added dropwise
and the mixture was allowed to warm to ambient temperature and
stirred for 5 h during which time a precipitate formed.
HCl.sub.(aq) (10 .mu.l, 37%) was added and the mixture was stirred
for a further 15 min. The mixture was centrifuged for 15 min (3000
g) and the resulting precipitate collected. Acetonitrile (0.5 mL)
was added and the mixture was centrifuged for a further 15 min. The
acetonitrile wash and centrifugation was repeated a further two
times and the resulting solid was dried under high vacuum to give
compound 7 (4 mg, 75%). .sup.1H NMR (500 MHz, D.sub.2O): .delta.
5.22 (d, J=1.6 Hz, 1H), 4.34 (dt, J=13, 1.6 Hz, 1H), 4.29-4.27 (m,
1H), 4.24-4.18 (m, 1H), 3.94 (br m, 1H), 3.44 (t, J=1.4 Hz, 1H).
.sup.31P NMR (500 MHz, D.sub.2O): .delta. -4.8 MS-ESI+ for
C.sub.10H.sub.15N.sub.5O.sub.8P.sup.+, (M+H).sup.+ calcd. 364.0653.
found 364.0652.
Example 2
Comparison of Precursor Z (cPMP) Prepared Synthetically to that
Prepared from E. coli in the In Vitro Synthesis of Moco
[0312] In vitro synthesis of Moco was compared using samples of
synthetic precursor Z (cPMP) and cPMP purified from E. coli. Moco
synthesis also involved the use of the purified components E. coli
MPT synthase, gephyrin, molybdate, ATP, and apo-sulfite oxidase.
See U.S. Pat. No. 7,504,095 and "Biosynthesis and molecular biology
of the molybdenum cofactor (Moco)" in Metal Ions in Biological
Systems, Mendel, Ralf R. and Schwarz, Gunter, Informa Plc, 2002,
Vol. 39, pages 317-68. The assay is based on the conversion of cPMP
into MPT, the subsequent molybdate insertion using recombinant
gephyrin and ATP, and finally the reconstitution of human
apo-sulfite oxidase.
[0313] As shown in FIG. 1, Moco synthesis from synthetic cPMP was
confirmed, and no differences in Moco conversion were found in
comparison to E. coli purified cPMP.
Example 3
Comparison of Precursor Z (cPMP) Prepared Synthetically to that
Prepared from E. coli in the In Vitro Synthesis of MPT
[0314] In vitro synthesis of MPT was compared using samples of
synthetic precursor Z (cPMP) and cPMP purified from E. coli. MPT
synthesis also involved the use of in vitro assembled MPT synthase
from E. coli. See U.S. Pat. No. 7,504,095 and "Biosynthesis and
molecular biology of the molybdenum cofactor (Moco)" in Metal Ions
in Biological Systems, Mendel, Ralf R. and Schwarz, Gunter, Informa
Plc, 2002, Vol. 39, pages 317-68. Three repetitions of each
experiment were performed and are shown in FIGS. 2 and 3.
[0315] As shown in FIGS. 2 and 3, MPT synthesis from synthetic cPMP
confirmed, and no apparent differences in MPT conversion were found
when compared to E. coli purified cPMP. A linear conversion of cPMP
into MPT is seen in all samples confirming the identity of
synthetic cPMP (see FIG. 2). Slight differences between the
repetitions are believed to be due to an inaccurate concentration
determination of synthetic cPMP given the presence of interfering
chromophores.
Example 4
Preparation of Precursor Z (cPMP)
A. Preparation of Starting Materials
##STR00221##
[0316] B. Introduction of the Protected Phosphate
##STR00222##
[0317] The formation of the cyclic phosphate using intermediate
[10] (630 mg) gave the desired product [11] as a 1:1 mixture of
diastereoisomers (494 mg, 69%).
##STR00223##
C. Oxidation and Overall Deprotection of the Molecule
[0318] Oxidation of the secondary alcohol to the gem-diol did prove
successful on intermediate [12], but the oxidized product [13] did
show significant instability and could not be purified. For this
reason, deprotection of the phosphate was attempted before the
oxidation. However, the reaction of intermediate [11] with TMSBr
led to complete deprotection of the molecule giving intermediate
[14]. An attempt to oxidize the alcohol to the gem-diol using
Dess-Martin periodinane gave the aromatized pteridine [15].
[0319] Oxidation of intermediate [11] with Dess-Martin periodinane
gave a mixture of starting material, oxidized product and several
by-products. Finally, intermediate [11] was oxidized using the
method described Example 1. Upon treatment, only partial oxidation
was observed, leaving a 2:1 mixture of [11]/[16]. The crude mixture
was submitted to the final deprotection. An off white solid was
obtained and analyzed by .sup.1H-NMR and HPLC-MS. These analyses
suggest that cPMP has been produced along with the deprotected
precursor [11].
[0320] Because the analytical HPLC conditions gave a good
separation of cPMP from the major impurities, this method will be
repeated on a prep-HPLC in order to isolate the final material.
* * * * *