U.S. patent application number 11/141612 was filed with the patent office on 2005-10-13 for preparation of trans-fused 3,3a,8,12b-tetrahydro-2h-dibenzo[3,4:6,7]cycloh- epta[1,2-b]furan derivatives.
Invention is credited to Brossette, Thierry, Compernolle, Frans Josef Cornelius, Guillaume, Michel Joseph Maurice Andre, Hoornaert, Georges Joseph Cornelius, Kozlecki, Tomasz, Lang, Yolande Lydia, Mao, Hua, Medaer, Bart Petrus Anna Maria Jozef.
Application Number | 20050228043 11/141612 |
Document ID | / |
Family ID | 8181460 |
Filed Date | 2005-10-13 |
United States Patent
Application |
20050228043 |
Kind Code |
A1 |
Lang, Yolande Lydia ; et
al. |
October 13, 2005 |
Preparation of trans-fused
3,3a,8,12b-tetrahydro-2H-dibenzo[3,4:6,7]cycloh- epta[1,2-b]furan
derivatives
Abstract
The present invention concerns processes for the preparation of
each of the 4 diastereomers of formula (I) 1 in stereochemically
pure form from either of two enantiomerically pure precursors. The
tetracyclic ringsystem having trans-fused five and seven membered
rings is formed in an acid-catalysed cyclization reaction. The
invention further relates to the thus obtained cis-fused
tetracyclic alcohol intermediates, the methanamine end-products,
the methanamine end-products for use as a medicine, in particular
as CNS active medicines.
Inventors: |
Lang, Yolande Lydia;
(Vosselaar, BE) ; Medaer, Bart Petrus Anna Maria
Jozef; (Lille, BE) ; Hoornaert, Georges Joseph
Cornelius; (Kessel-Lo, BE) ; Brossette, Thierry;
(Montpellier, FR) ; Compernolle, Frans Josef
Cornelius; (Herent, BE) ; Guillaume, Michel Joseph
Maurice Andre; (Berg, BE) ; Mao, Hua; (Leuven,
BE) ; Kozlecki, Tomasz; (Leuven, BE) |
Correspondence
Address: |
PHILIP S. JOHNSON
JOHNSON & JOHNSON
ONE JOHNSON & JOHNSON PLAZA
NEW BRUNSWICK
NJ
08933-7003
US
|
Family ID: |
8181460 |
Appl. No.: |
11/141612 |
Filed: |
May 31, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11141612 |
May 31, 2005 |
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10496279 |
May 21, 2004 |
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10496279 |
May 21, 2004 |
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PCT/EP02/13560 |
Dec 2, 2002 |
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Current U.S.
Class: |
514/468 ;
549/457 |
Current CPC
Class: |
A61P 25/06 20180101;
A61P 25/22 20180101; A61P 25/30 20180101; C07D 307/93 20130101;
A61P 25/24 20180101; A61P 25/28 20180101 |
Class at
Publication: |
514/468 ;
549/457 |
International
Class: |
C07D 307/93; A61K
031/343 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 7, 2001 |
EP |
01204961.5 |
Claims
1. A process for preparing each individual diastereoisomer of
formula (I): 39wherein the substituents on carbon atoms 3a and 12b
have the trans configuration, the substituent on carbon atom 2 may
have the R or the S configuration, comprising the step of cyclizing
a compound of formula (II) 40wherein R represents C.sub.1-3
alkylcarbonyl; OR.sup.1 represents a leaving group and the
substituents --OR and --CH.sub.2--CHOH--CH.sub.2O- R.sup.1 have the
cis configuration, in a reaction inert solvent in the presence of
an acid, whereby 4142
2. A process according to claim 1 wherein each individual
diastereomer of formula (I) is converted further into a target
compound of formula (III) comprising the further steps of reacting
the intermediate compound of formula (I) with aqueous or gaseous
methylamine in an organic solvent at an elevated temperature, thus
yielding 43
3. A process according to claim 1 wherein the compound of formula
(II) 44wherein OR.sup.1 is a leaving group and the substituents
--OR and --CH.sub.2--CHOH--CH.sub.2--OR.sup.1 have the cis
configuration is prepared from a diol of formula 45wherein the
substituents --OR and --CH.sub.2--CHOH--CH.sub.2--OH have the cis
configuration by selective conversion of the primary hydroxyl group
into a leaving group, through reaction with a sulfonylchloride in a
reaction-inert solvent, in the presence of an excess of base, and
optionally in the presence of dimethylaminopyridine and/or
dibutyl(oxo)stannane.
4. A process according to claim 3 wherein the intermediate diol of
formula (IV) 46wherein the substituents have the cis configuration
is prepared from a ketone of formula (V) 47by the following series
of reaction steps (a) reduction of the ketone to the cis-oriented
hydroxyl group by reaction with lithium or sodium borohydride in a
mixture of an organic solvent and an aqueous buffer having a pH of
about 7 at a temperature below ambient temperature; (b) acylation
of the hydroxyl group following art-known procedures; and (c)
deacetalisation in an organic solvent in the presence of an acid,
whereby 4849
5. A process according to claim 4 wherein the ketone of formula (V)
50is prepared from a pro-chiral ketone of formula (VIII) and
(4S)-2,2-dimethyl-1,3-dioxolane-4-carboxaldehyde or
(4R)-2,2-dimethyl-1,3-dioxylane-4-carboxaldehyde (VII) in an aldol
reaction, 51yielding unsaturated ketone (VI) and reducing said
unsaturated ketone to a mixture of epimeric ketones (V-a) and (V-c)
or (V-b) and (V-d), and optionally converting (V-c) into (V-a), or
(V-b) into (V-d) by treatment with a base in a suitable solvent at
a temperature in the range of 35.degree. C.-45.degree. C.
6. An intermediate compound of formula (I) having the formula
52wherein OR.sup.1 represents a leaving group.
7. A compound of formula (III) having the formula 53in free base
form or a pharmaceutically acceptable acid addition salt form
thereof.
8. A compound of formula (II) according to claim 7 for use as a
medicine.
9. A compound according to claim 8 for use as a CNS active
medicine.
Description
[0001] The present invention concerns processes for the preparation
of each of the 4 diastereomers of trans-fused
3,3a,8,12b-tetrahydro-2H-diben- zo[3,4:6,7]cyclohepta [1,2-b]furan
derivatives in stereochemically pure form from either of two
enantiomerically pure precursors. The tetracyclic ring system
having trans-fused five and seven membered rings is formed in an
acid-catalysed cyclization reaction. The invention further relates
to the thus obtained cis-fused tetracyclic alcohol intermediates,
the methanamine end-products, the methanamine end-products for use
as a medicine, in particular as CNS active medicines.
[0002] An article by Monkovic et al. (J. Med. Chem. (1973), 16(4),
p. 403-407) describes the synthesis of
(.+-.)-3,3a,8,12b-tetrahydro-N-methyl-
-2H-dibenzo[3,4:6,7]-cyclohepta-[1,2-b]furan-2-methanamine oxalic
acid. Said compound was synthesized as a potential antidepressant;
however, it was found that this particular tetrahydrofurfurylamine
derivative was inactive as an antidepressant at a dose of 300
mg/kg.
[0003] WO 97/38991, published on 23 Oct. 1997, discloses
tetracyclic tetrahydrofuran derivatives of formula 2
[0004] wherein the hydrogen atoms on carbon atoms 3a and 12b have
the trans configuration. The 4 possible trans products are obtained
from a racemic intermediate in a non-selective cyclization reaction
and can be separated from one another using HPLC techniques.
[0005] WO 99/19317, published on 22 Apr. 1999, concerns halogen
substituted tetracyclic tetrahydrofuran derivatives of formula
3
[0006] wherein the hydrogen atoms on carbon atoms 3a and 12b have
the trans configuration. The 4 possible trans products are obtained
from a racemic intermediate in a non-selective cyclization reaction
and can be separated from one another using HPLC techniques.
[0007] As the method for preparing the trans-fused compounds proved
ill-suited for upscaling, alternative routes for synthesis of these
trans-fused compounds were explored, one of which opened a pathway
to each of the 4 diastereomers of the previously unknown cis-fused
3,3a,8,12b-tetrahydro-2H-dibenzo[3,4:6,7]cyclohepta[1,2-b]furan
derivatives from a single enantiomeric precursor. This route allows
for the synthesis of two of the four trans diastereomers; the
enantiomers thereof can be prepared starting from the other
enantiomer of the precursor.
[0008] The present invention concerns a process for preparing each
of the 4 individual diastereomers of formula (I) 4
[0009] wherein the substituents on carbon atoms 3a and 12b have the
trans configuration and the substituent on carbon atom 2 may have
the R or the S configuration, comprising the step of cyclizing a
compound of formula (II) 5
[0010] wherein R represents C.sub.1-3alkylcarbonyl;
[0011] OR.sup.1 is a leaving group; and
[0012] the substituents --OR and --CH.sub.2--CHOH--CH.sub.2OR.sup.1
have the cis configuration, in a reaction inert solvent in the
presence of a acid, whereby 67
[0013] C.sub.1-3alkylcarbonyl represents methylcarbonyl,
ethylcarbonyl and propylcarbonyl; the term `a leaving group`
represents sulfonyloxy groups such as methanesulfonyloxy,
trifluoromethanesulfonyloxy, benzenesulfonyloxy,
4-methylbenzenesulfonyloxy, 4-nitrobenzenesulfonyloxy and
4-bromobenzenesulfonyloxy.
[0014] Suitable solvents are, for example, aromatic hydrocarbons,
e.g. benzene, toluene, chlorobenzene; halogenated hydrocarbons,
e.g. dichloromethane, trichloromethane; acetonitrile. Suitable
acids are, for example, sulfonic acids, e.g. methanesulfonic,
trifluoromethanesulfonic, benzenesulfonic, 4-methylbenzenesulfonic,
camphorsulfonic acid; carboxylic acids, e.g. acetic or
trifluoroacetic acid. The reaction can conveniently be conducted by
stirring the reagent, substrate and solvent at ambient
temperature.
[0015] Under the reaction conditions, an internally solvated
benzylic cation may form as an intermediate which cyclizes to a
tetrahydrofuran ring with trans-fusion.
[0016] The numbering of the tetracyclic ring-system present in the
compounds of formula (I), as defined by Chemical Abstracts
nomenclature is shown in formula (I'). 8
[0017] The compounds of formula (I) have at least three asymmetric
centers, namely carbon atom 2, carbon atom 3a and carbon atom 12b.
Carbon atoms 3a and 12b are part of an annelated ring system. In
this case, where more than 2 asymmetric carbon atoms are present on
a ring system, the substituent highest in priority (according to
the Cahn-Ingold-Prelog sequence rules) on the reference carbon
atom, which is defined as the asymmetric carbon atom having the
lowest ring number, is arbitrarily always in the ".alpha." position
of the mean plane determined by the ring system. The position of
the highest priority substituent on the other asymmetric carbon
atoms relative to the position of the highest priority substituent
on the reference atom is denominated by ".alpha." or ".beta.".
".alpha." means that the highest priority substituent is on the
same side of the mean plane determined by the ring system, and
".beta." means that the highest priority substituent is on the
other side of the mean plane determined by the ring system.
[0018] Of some compounds of formula (I) and of intermediates used
in their preparation, the absolute stereochemical configuration was
not experimentally determined. In those cases the stereochemically
isomeric form which was first isolated is designated as "A" and the
second as "B", without further reference to the actual
stereochemical configuration. However, said "A" and "B" isomeric
forms can be unambiguously characterized by for instance their
optical rotation in case "A" and "B" have an enantiomeric
relationship. A person skilled in the art is able to determine the
absolute configuration of such compounds using art-known methods
such as, for example, X-ray diffraction.
[0019] The following table summarizes the nomenclatures using
absolute and relative stereodescriptors of each of the four
trans-stereoisomers of the compound of formula (I).
1 Absolute configuration Relative configuration 2 3a 12b 2 3a 12b R
R S .alpha. .alpha. .beta. R S R .alpha. .beta. .alpha. S R S
.alpha. .beta. .alpha. S S R .alpha. .alpha. .beta.
[0020] The tetracyclic sulfonates of formula (I) can be converted
further into target compounds of pharmaceutical interest by further
reaction with aqueous or gaseous methanamine in an organic solvent
at an elevated temperature, thus yielding 9
[0021] A suitable organic solvent is for example tetrahydrofuran.
The reaction is preferably conducted in a pressure vessel at a
temperature in the range of 120.degree. C. to 150.degree. C.
[0022] Each of the intermediate compounds of formula 10
[0023] is prepared from a diol of formula 11
[0024] by chemoselective conversion of the primary hydroxyl group
into a leaving group. One such method comprises stirring the diol
of formula (IV) in a reaction inert solvent such as a halogenated
hydrocarbon, e.g. dichloromethane, in the presence of an excess of
a base such as triethylamine, an equivalent of
dimethylaminopyridine and half an equivalent of
dibutyl(oxo)stannane, and two equivalents of tosylchloride or a
similar sulfonylchloride. The reaction may also be conducted in the
absence of dibutyl(oxo)stannane and dimethylaminopyridine but
typically will yield a mixture of substrate, mono- and
disubstituted product from which the desired monosubstituted
compound needs to be separated.
[0025] The intermediate diol of formula (IV) can be prepared from a
ketone of formula (V) 12
[0026] by the following series of reaction steps:
[0027] (a) reducing the ketone of formula (V) to the cis-oriented
hydroxyl group by reaction with lithium or sodium borohydride in a
mixture of an organic solvent and an aqueous buffer having a pH of
about 7 at a temperature below ambient temperature;
[0028] (b) acylating the hydroxyl group with an acylchloride or
acyl anhydride following art-known procedures, and 13
[0029] (c) unmasking the diol by a deacetalisation reaction in an
organic solvent in the presence of an acid, whereby 1415
[0030] The intermediate ketones of formula (V) are prepared from
the .alpha.,.beta.-unsaturated ketone (VI)
[0031] by either Pd/C catalyzed hydrogenation or a reduction
procedure using sodiumcyanoborohydride, yielding a mixture of
epimeric ketones (V-a) and (V-c), or (V-b) and (V-d), in a rather
invariant ratio of about 3:2.
[0032] The hydrogenation reaction may conveniently be conducted in
a variety of solvents such as alcohols, e.g. methanol, ethanol,
isopropanol; esters, e.g. ethyl acetate; ethers, e.g.
tetrahydrofuran; aromatic hydrocarbons, e.g. toluene; optionally in
the presence of a tertiairy amine such as triethylamine or
quinine.
[0033] Reduction of (VI) can be accomplished with sodium
cyanoborohydride under slightly acidic conditions.
[0034] The epimeric ketones (V-a) and (V-c), or (V-b) and (V-d),
can be obtained separately by chromatographic separation
(diethylether/hexane 60/40). Separation can also be effected on the
epimeric alcohols obtained following reduction of (V) according to
step (a).
[0035] The epimeric ketone of formula (V-c) may be converted into
the epimeric ketone of formula (V-a) by treatment with a base such
as triethylamine in a suitable solvent such as isopropanol at a
slightly elevated temperature in the range of 35.degree.
C.-45.degree. C. The epimeric ketone (V-b) may likewise be
converted into (V-d).
[0036] To prepare intermediate (VI),
(4S)-2,2-dimethyl-1,3-dioxolane-4-car- boxaldehyde (VII) (or its
enantiomer) and pro-chiral ketone (VIII) can be dissolved in a
suitable solvent such as tetrahydrofuran and treated with a base
such as tert butyloxypotassium salt and a co-reagent such as
magnesium chloride or bromide (aldol condensation). 16
[0037] The pro-chiral ketone (VIII) can be prepared by adaption of
an art-known sequence (Can. J. Chem., 1971, 49, 746-754) starting
with a Friedel-Crafts acylation reaction using fluorobenzene and
phthalic anhydride to form keto-acid (IX), followed by reductive
removal of the ketone group and homologation of the carboxylic acid
function. 17
[0038] Cyclization of the homologous acid (X) in another
Friedel-Crafts acylation affords ketone (VIII).
[0039] The process according to the present invention provides an
enantioselective approach to the target molecule (III) in
enantiopure form via the enantiopure sulfonates of formula (I).
Both target and intermediate molecules of formulae (III) and (I)
are novel.
[0040] The pharmaceutically active compounds of formula (III) may
occur in their free form as a base or in a pharmaceutically
acceptable salt form obtained by treatment of the free base with an
appropriate non-toxic acid such as an inorganic acid, for example,
hydrohalic acid, e.g. hydrochloric or hydrobromic, sulfueric,
nitric, phosphoric and the like acids; or an organic acid, such as,
for example, acetic, hydroxyacetic, propanoic, lactic, pyruvic,
oxalic, malonic, succinic, maleic, fumaric, malic, tartaric,
citric, methanesulfonic, ethanesulfonic, benzenesulfonic,
p-toluenesulfonic, cyclamic, salicylic, p-aminosalicylic, pamoic
and the like acids.
[0041] The term addition salt as used hereinabove also comprises
the solvates which the compounds of formula (I) as well as the
salts thereof, are able to form. Such solvates are for example
hydrates, alcoholates and the like.
[0042] The term `enantiopure form` designates compounds and
intermediates having a stereoisomeric excess of at least 80% (i.e.
minimum 90% of one isomer and maximum 10% of the other possible
isomers) up to a stereoisomeric excess of 100% (i.e. 100% of one
isomer and none of the other), more in particular, compounds or
intermediates having a stereoisomeric excess of 90% up to 100%,
even more in particular having a stereoisomeric excess of 94% up to
100% and most in particular having a stereoisomeric excess of 97%
up to 100%.
[0043] The compounds of the present invention show affinity for
5-HT.sub.2 receptors, particularly for 5-HT.sub.2A and 5-HT.sub.2C
receptors (nomenclature as described by D. Hoyer in "Serotonin
(5-HT) in neurologic and psychiatric disorders" edited by M. D.
Ferrari and published in 1994 by the Boerhaave Commission of the
University of Leiden). The serotonin antagonistic properties of the
present compounds may be demonstrated by their inhibitory effect in
the "5-hydroxytryptophan Test on Rats" which is described in Drug
Dev. Res., 13, 237-244 (1988). Furthermore, the compounds of the
present invention show interesting pharmacological activity in the
"mCPP Test on Rats" which is described hereinafter, and in the
"Combined Apomorphine, Tryptamine, Norepinephrine (ATN) Test on
Rats" which is described in Arch. Int. Pharmacodyn, 227, 238-253
(1977).
[0044] In view of these pharmacological and physicochemical
properties, the compounds of formula (III) are useful as
therapeutic agents in the treatment or the prevention of central
nervous system disorders like anxiety, depression and mild
depression, bipolar disorders, sleep- and sexual disorders,
psychosis, borderline psychosis, schizophrenia, migraine,
personality disorders or obsessive-compulsive disorders, social
phobias or panic attacks, organic mental disorders, mental
disorders in children, aggression, memory disorders and attitude
disorders in older people, addiction, obesity, bulimia and similar
disorders. In particular, the present compounds may be used as
anxiolytics, antipsychotics, antidepressants, anti-migraine agents
and as agents having the potential to overrule the addictive
properties of drugs of abuse.
[0045] The compounds of formula (III) may also be used as
therapeutic agents in the treatment of motoric disorders. It may be
advantageous to use the present compounds in combination with
classical therapeutic agents for such disorders.
[0046] The compounds of formula (III) may also serve in the
treatment or the prevention of damage to the nervous system caused
by trauma, stroke, neurodegenerative illnesses and the like;
cardiovascular disorders like high blood pressure, thrombosis,
stroke, and the like; and gastrointestinal disorders like
dysfunction of the motility of the gastrointestinal system and the
like.
[0047] In view of the above uses of the compounds of formula (III),
it follows that the present invention also provides a method of
treating warm-blooded animals suffering from such diseases, said
method comprising the systemic administration of a therapeutic
amount of a compound of formula (III) effective in treating the
above described disorders, in particular, in treating anxiety,
psychosis, schizophrenia, depression, migraine, sleep disorders and
addictive properties of drugs of abuse.
[0048] The present invention thus also relates to compounds of
formula (III) as defined hereinabove for use as a medicine, in
particular, the compounds of formula (III) may be used for the
manufacture of a medicament for treating anxiety, psychosis,
schizophrenia, depression, migraine, sleep disorders and addictive
properties of drugs of abuse.
[0049] Those of skill in the treatment of such diseases could
determine the effective therapeutic daily amount from the test
results presented hereinafter. An effective therapeutic daily
amount would be from about 0.01 mg/kg to about 10 mg/kg body
weight, more preferably from about 0.05 mg/kg to about 1 mg/kg body
weight.
[0050] For ease of administration, the subject compounds may be
formulated into various pharmaceutical forms for administration
purposes. To prepare the pharmaceutical compositions of this
invention, a therapeutically effective amount of the particular
compound, optionally in addition salt form, as the active
ingredient is combined in intimate admixture with a
pharmaceutically acceptable carrier, which may take a wide variety
of forms depending on the form of preparation desired for
administration. These pharmaceutical compositions are desirably in
unitary dosage form suitable, preferably, for administration
orally, rectally, percutaneously, or by parenteral injection. For
example, in preparing the compositions in oral dosage form, any of
the usual pharmaceutical media may be employed, such as, for
example, water, glycols, oils, alcohols and the like in the case of
oral liquid preparations such as suspensions, syrups, elixirs and
solutions; or solid carriers such as starches, sugars, kaolin,
lubricants, binders, disintegrating agents and the like in the case
of powders, pills, capsules and tablets. Because of their ease in
administration, tablets and capsules represent the most
advantageous oral dosage unit form, in which case solid
pharmaceutical carriers are obviously employed. For parenteral
compositions, the carrier will usually comprise sterile water, at
least in large part, though other ingredients, for example, to aid
solubility, may be included. Injectable solutions, for example, may
be prepared in which the carrier comprises saline solution, glucose
solution or a mixture of saline and glucose solution. Injectable
solutions containing compounds of formula (III) may be formulated
in an oil for prolonged action. Appropriate oils for this purpose
are, for example, peanut oil, sesame oil, cottonseed oil, corn oil,
soy bean oil, synthetic glycerol esters of long chain fatty acids
and mixtures of these and other oils. Injectable suspensions may
also be prepared in which case appropriate liquid carriers,
suspending agents and the like may be employed. In the compositions
suitable for percutaneous administration, the carrier optionally
comprises a penetration enhancing agent and/or a suitable wettable
agent, optionally combined with suitable additives of any nature in
minor proportions, which additives do not cause any significant
deleterious effects on the skin. Said additives may facilitate the
administration to the skin and/or may be helpful for preparing the
desired compositions. These compositions may be administered in
various ways, e.g., as a transdermal patch, as a spot-on or as an
ointment. Acid or base addition salts of compounds of formula (III)
due to their increased water solubility over the corresponding base
or acid form, are more suitable in the preparation of aqueous
compositions.
[0051] In order to enhance the solubility and/or the stability of
the compounds of formula (III) in pharmaceutical compositions, it
can be advantageous to employ .alpha.-, .beta.- or
.gamma.-cyclodextrins or their derivatives, in particular
hydroxyalkyl substituted cyclodextrins, e.g.
2-hydroxypropyl-.beta.-cyclodextrin. Also co-solvents such as
alcohols may improve the solubility and/or the stability of the
compounds of formula (III) in pharmaceutical compositions.
[0052] Other convenient ways to enhance the solubility of the
compounds of the present invention in pharmaceutical compositions
are described in WO 97/44014.
[0053] More in particular, the present compounds may be formulated
in a pharmaceutical composition comprising a therapeutically
effective amount of particles consisting of a solid dispersion
comprising a compound of formula (III), and one or more
pharmaceutically acceptable water-soluble polymers.
[0054] The term "a solid dispersion" defines a system in a solid
state (as opposed to a liquid or gaseous state) comprising at least
two components, wherein one component is dispersed more or less
evenly throughout the other component or components. When said
dispersion of the components is such that the system is chemically
and physically uniform or homogenous throughout or consists of one
phase as defined in thermodynamics, such a solid dispersion is
referred to as "a solid solution". Solid solutions are preferred
physical systems because the components therein are usually readily
bioavailable to the organisms to which they are administered.
[0055] The term "a solid dispersion" also comprises dispersions
which are less homogenous throughout than solid solutions. Such
dispersions are not chemically and physically uniform throughout or
comprise more than one phase.
[0056] The water-soluble polymer in the particles is a polymer that
has an apparent viscosity of 1 to 100 mPa.multidot.s when dissolved
in a 2% aqueous solution at 20.degree. C. solution.
[0057] Preferred water-soluble polymers are hydroxypropyl
methylcelluloses or HPMC. HPMC having a methoxy degree of
substitution from about 0.8 to about 2.5 and a hydroxypropyl molar
substitution from about 0.05 to about 3.0 are generally
water-soluble. Methoxy degree of substitution refers to the average
number of methyl ether groups present per anhydroglucose unit of
the cellulose molecule. Hydroxy-propyl molar substitution refers to
the average number of moles of propylene oxide which have reacted
with each anhydroglucose unit of the cellulose molecule.
[0058] The particles as defined hereinabove can be prepared by
first preparing a solid dispersion of the components, and then
optionally grinding or milling that dispersion. Various techniques
exist for preparing solid dispersions including melt-extrusion,
spray-drying and solution-evaporation, melt-extrusion being
preferred.
[0059] It is especially advantageous to formulate the
aforementioned pharmaceutical compositions in dosage unit form for
ease of administration and uniformity of dosage. Dosage unit form
as used in the specification and claims herein refers to physically
discrete units suitable as unitary dosages, each unit containing a
predetermined quantity of active ingredient calculated to produce
the desired therapeutic effect, in association with the required
pharmaceutical carrier. Examples of such dosage unit forms are
tablets (including scored or coated tablets), capsules, pills,
powder packets, wafers, injectable solutions or suspensions,
teaspoonfuls, tablespoonfuls and the like, and segregated multiples
thereof.
EXPERIMENTAL PART
[0060] Hereinafter, "DMF" is defined as N,N-dimethylformamide,
"THF" is defined as tetrahydrofuran, "DIPE" is defined as
diisopropyl ether, "HCl.sub.cp" is defined as chemically pure
hydrochloric acid (34.5% w/w).
[0061] A. Preparation of the Intermediate Compounds
Example A1a
Intermediate 1: 2-(4-fluorobenzoyl)benzoic Acid--CAS RN
[7649-29-5]
[0062] (i) A solution of p-fluorobenzenemagnesium bromide (1.2M
solution in THF, 1 eq.) was added to a 0.4M solution of phthalic
anhydride in THF, so that the temperature remained under 30.degree.
C. After 1 h, half of the solvent was distilled off and the
reaction mixture was stirred overnight at room temperature. The
obtained precipitate was filtered off and taken up in water (0.3
L/mol). Toluene (1 L/mol) and HCl.sub.cp were added so that the
temperature remained under 35.degree. C. After stirring 1 h, the
organic layer was evaporated (50.degree. C., vac.) and the obtained
solid was dried at 50.degree. C. under vacuum.
[0063] Physical yield: 74%
[0064] Purity: 93% (LC abs %)Active yield: 69% of intermediate
1
[0065] (ii) Alternatively, a Friedel-Crafts reaction can be
performed:
[0066] Phthalic anhydride, fluorobenzene (1.2 eq.) and
CH.sub.2Cl.sub.2 (0.5 L/mol) were mixed at room temperature.
AlCl.sub.3 (0.8 eq.) was added over 60 min. (at 1 mol scale). After
5 h at room temperature, the mixture was heated up to reflux during
18 h, then cooled down to room temperature and poured very slowly
in ice/water and stirred during 1 h. The organic layer was
separated and the water layer was extracted with CH.sub.2Cl.sub.2
(0.25 L/mol) The combined organic layers were washed with water
(0.3 L/mol), then extracted with 320 ml water (0.7 L/mol)/NaOH 50%
(0.07 L/mol). The water layer was separated and washed with 60 ml
CH.sub.2Cl.sub.2 (0.15 L/mol) Norit-A-Supra (active charcoal) (10
g/mol) was added and the mixture was stirred and filtered.
[0067] Water (0.7 L/mol)/HCl.sub.cp (2.5 eq.) solution was added
dropwise, the mixture was stirred during 30 min., the precipitate
filtered off, washed with water (2.times.0.2 L/mol) and dried.
[0068] Yield: 92% of intermediate 1.
Example A1b
Intermediate 2: 2-[(4-fluorophenyl)methyl]benzoic Acid--CAS RN
[346-47-4]
[0069] Intermediate 1 was dissolved in isopropanol (2 L/mol) and
Pd/C (10% dry) was added. The reaction mixture was heated up to
45.degree. C. and hydrogenated overnight at atmospheric pressure.
After cooling the flask to room temperature, the catalyst was
filtered off over diatomaceous earth and rinsed with 30 ml
isopropanol. The filtrate was evaporated at 45.degree. C. under
vacuum.
[0070] Physical yield: 98%
[0071] Purity: 96.4% (LC abs %)Active yield: 94% of intermediate
2
Example A1c
[0072] Preparation of Intermediate 3 18
[0073] Intermediate 2 was dissolved in toluene (1.5 L/mol) and DMF
(1 ml/mol) was added. The reaction mixture was heated up to
40.degree. C. and thionyl chloride (1.1 eq.) was added. During the
addition the reaction mixture was further heated up to 50.degree.
C. The reaction mixture was stirred at 50.degree. C. during 2h30,
then evaporated at 50.degree. C. under vacuum. THF (0.3 L/mol) was
added and that solution was dropped into a 2M NaBH.sub.4 solution
in THF (1.5 eq.). The temperature rose to reflux (67.degree. C.)
and the reaction mixture was stirred at reflux during 2 h. The
reaction mixture was cooled down to room temperature. Aceton (350
ml/mol) was added (temperature rose to 40.degree. C.), the reaction
mixture was stirred during 30 minutes, followed by toluene (1
L/mol) and water (1.5 L/mol). The reaction mixture was heated up to
50.degree. C. and the organic layer evaporated at 50.degree. C.
under vacuum. CH.sub.2Cl.sub.2 (3 L/mol) was added, followed by
triethylamine (1.1 eq.). SOCl.sub.2 (1.1 eq.) was added dropwise,
the temperature rose to reflux. The reaction mixture was stirred
during 45 min to room temperature. Water (1 L/mol) was added and
the reaction mixture was stirred vigorously during 15 min. The
organic layer was washed a second time with water (1 L/mol) and
evaporated (40.degree. C., vac.). The product was dissolved in
toluene (2.5 L/mol), tetrabutylammonium hydrogenosulfate
(phase-transfer reagent) (0.1 eq.) was added at 70.degree. C. NaCN
6M (1.6 eq.) was added at 70.degree. C. under vigorous stirring.
The reaction mixture was then heated up to reflux and stirred 3 h.
After cooling down to room temperature, water (0.5 L/mol) was
added, the reaction mixture was stirred during 30 minutes. After
washing a second time with water (0.5 L/mol), drying on MgSO.sub.4
and evaporating the solvent, intermediate 3 was obtained.
[0074] Physical yield: 98%
[0075] Purity: 96.4% (LC abs %)Active yield: 94% of intermediate
3
Example A1d
[0076] Preparation of Intermediate 4 19
[0077] Intermediate 3 was suspended in acetic acid (0.5 L/mol),
water (0.3 L/mol) and sulfuric acid (0.35 L/mol). After 5 h at
reflux, the mixture was cooled down, water (1.2 L/mol) and
dichloromethane (0.3 L/mol) were added. The organic extract was
washed with water (1.3 L/mol) and NaOH 50% (0.15 L/mol). After
stirring 20 min., the aqueous layer was separated and washed with
CH.sub.2Cl.sub.2 (0.1 L/mol), which was discarded. The aqueous
layer was acidified with HCl.sub.cp (2 eq.). The mixture was
stirred during 3 h, the precipitate was then filtered off and
washed with water (0.1 L/mol).
[0078] Yield: 74% of intermediate 4
Example A1e
[0079] Preparation of Intermediate 5 20
[0080] Intermediate 4 was dissolved in dichloromethane (0.6 L/mol)
and N,N-dimethyl acetamide, 15 ml/mol). Thionyl chloride (1 eq.)
was added dropwise and the reaction mixture was refluxed during
1h30. After cooling down to 0.degree. C., AlCl.sub.3 (1 eq.) was
added and the mixture was stirred during 2 h. HCl.sub.cp (2 eq.)
and water (0.3 L/mol) were added. The layers were separated, the
organic layer was washed with 5% NaHCO.sub.3 solution (0.6 L/mol),
then with water. The organic layer was evaporated, isopropanol
(0.25 L/mol) was added. The mixture was heated up to reflux (30
min.) and cooled down. Seeding occured at 65.degree. C. After
cooling down further and stirring 2 h at room temperature, the
precipitate was filtered off, washed with isopropanol (0.05 L/mol)
and dried at 50.degree. C. under vacuum.
[0081] Yield: 40-80% of intermediate 5.
[0082] Typical purity between 77% and 93%
Example A1f
[0083] Preparation of Intermediate 6 21
[0084] Intermediate 5 was dissolved in toluene (2 L/mol).
MgCl.sub.2 anhydrous (1.2 eq.) was added and the reaction mixture
was stirred at room temperature during 30 min. (S)-solketal
aldehyde (from DSM, 1.7 eq., 20% solution in THF) was added and in
one time 0.2 eq. potassium tert-butoxide. Slight exothermicity was
observed. The reaction mixture was stirred during 68 h at room
temperature. Water (0.5 L/mol) was added, followed by 0.2 eq.
HCl.sub.cp. The reaction mixture was stirred vigorously during 5
min. The organic layer was washed again with 0.5 L/mol water, then
again with 1 L/mol water. After adding Na.sub.2SO.sub.4 (125
g/mol), active carbon (40 g/mol), the mixture was filtered, the
remaining solid was rinsed with toluene (0.2 L/mol) and the
filtrate was evaporated. Isopropanol (1.5 L/mol) was added, the
reaction mixture was stirred at least 8 h at 20-25.degree. C., then
cooled down to 0-5.degree. C. and stirred at that temperature for
at least 2 h. The precipitate was filtered off, washed with cold
isopropanol (0.07 L/mol) and air-dried at 40.degree. C.
[0085] Physical yield: 58%
[0086] Purity: 93.1% (LC abs %)Active yield: 54% of intermediate
6.
[0087] The product could be recrystallized from iPrOH.
Example A2
[0088] a. Preparation of Intermediate 7 and Intermediate 8 22
[0089] Intermediate 6 was dissolved in acetone (2 L/mol),
triethylamine (1 eq.) and thiophene (4% solution in EtOH, 0.007
L/mol.) were added. After suspending Pd/C (60 g/mol, 10% wet), the
hydrogenation was performed. In case the conversion was low,
another 60 g/mol Pd/C was added and the hydrogenation was continued
till complete conversion. Some exothermicity was observed
(temperature rises to 35.degree. C.). When the reaction was
completed, the catalyst was filtered off over diatomaceous earth
and the solid was rinsed with acetone (0.07 L/mol). The filtrate
was evaporated (atm.) at 75-80.degree. C. The residue was cooled
down to 70-75.degree. C. Isopropanol was added (0.84 L/mol), then
evaporated again. The reaction mixture was cooled down. The pure
intermediate 7 and pure intermediate 8 could be obtained via
chromatographic separation (HPLC: Waters 515 pump, Merck Hibar.RTM.
250.times.25 mm column filled with Lichrosorb.RTM. SI 60 7 .mu.m;
Eluent: diether/hexane 60/40; flow rate: 11 mL/min). Yielding
intermediate 7 and intermediate 8 in a ratio of 3:2.
[0090] b. Conversion of Intermediate 8 to Intermediate 7.
[0091] Intermediate 6 (1.00 g, 2.96 mmol) was dissolved in i-PrOH
(30 ml). Et.sub.3N (0.63 ml, 4.50 mmol) and Pd/C were added and the
hydrogenation was performed for 6 hr. Then the mixture was
filtrated through celite and washed 4 times with CH.sub.2Cl.sub.2.
After evaporation, i-PrOH (5 ml), Et.sub.3N (1.20 ml) was added and
stirred at 40.degree. C. for 1 hr. The reaction mixture was cooled
to room temperature and allowed to crystallisation. The crystals
were filtered off and dried under vacuum to afford pure ketone as
white crystalline powder. Yielding intermediate 7 (0.86 g, 86%)
(mp. 144-146.degree. C.).
Example A3a
[0092] Preparation of Intermediate 9 23
[0093] In THF (1.4 L/mol), a buffer solution of pH 7 containing
potassium dihydrogen-phosphate and disodium hydrogenphosphate, 0.3
L/mol was added. The mixture was cooled down to 0-5.degree. C. and
intermediate 7 was added. Lithium borohydride 2N in THF (0.48 eq.)
was added and the temperature was maintained under 10.degree. C.
After the addition, the reaction mixture was stirred during 2 h at
0-5.degree. C. Acetone (1.7 eq.) was cautiously added and the
reaction mixture was stirred to room temperature. Water (0.7 L/mol)
was added at 10-25.degree. C. and the reaction mixture was stirred
30 min. at room temperature. Acetic acid (2.2 eq.) and 200 ml
toluene were added. After stirring during 10 min., the organic
layer was washed with water (0.36 L/mol) and NaOH 50% (2.2 eq.),
then washed again twice with water (0.45 L/mol). The solution was
evaporated (a viscous oil was obtained) and dichloromethane (1
L/mol) was added. The solution was used further in the next step,
assuming that 100% intermediate 9 had been obtained.
Example A3b
[0094] Preparation of Intermediate 10 24
[0095] Dimethylaminopyridine (0.05 eq.) and triethylamine (1.1 eq.)
were added to intermediate 9 (solution in CH.sub.2Cl.sub.2). Acetic
anhydride (1.1 eq.) was added dropwise. The temperature was allowed
to rise to 40.degree. C. The reaction mixture was stirred during 2
h and NH.sub.4Cl 1N (0.5 eq.). About 90% of the solvent was
distilled off (atmospheric pressure) and isopropanol (1 L/mol) was
added. About one fifth of the solvent was evaporated (atmospheric
pressure) and the reaction mixture was slowly cooled down to room
temperature and stirred overnight. After cooling down further to
0-5.degree. C. and stirring at that temperature during 8-16 h, the
precipitate was filtered off and washed with isopropanol (0.2
L/mol). The product was dried for 16 h at 50.degree. C. under
vacuum.
[0096] Active yield: 80% of intermediate 10.
Example A3c
[0097] Preparation of Intermediate 11 25
[0098] Intermediate 10 was suspended in water (0.3 L/mol) and
glacial acetic acid (0.45 L/mol) was added. This mixture was
stirred at 55.degree. C. for 8 hours. The reaction proceeded to 93%
conversion. The reaction mixture was cooled to ambient temperature.
Water (1.5 L/mol) and methylene chloride (0.8 L/mol) were charged
and the mixture was stirred for 15 minutes. The water phase was
separated and extracted three times with methylene chloride (each
time with 0.6 L/mol). The combined organic phases were washed with
water (1 L/mol) and dried over sodium sulfate. The solvent was
evaporated, yielding a fluffy white solid.
[0099] Active yield: 94% of intermediate 11.
Example A3d
[0100] Preparation of Intermediate 12 26
[0101] Intermediate 11 was dissolved in toluene (3.5 L/mol) and
p-toluenesulfonyl chloride (1.5 eq.) was added in one portion. To
this mixture, pyridine (10 eq.) was added dropwise. The reaction
mixture was stirred 4 h at 40.degree. C. Water (1.5 L/mol) was
added, followed by 1 M ammonium chloride (1.3 eq.). After drying
the organic phase over sodium sulfate, the organic solvent was
evaporated yielding crude product, which was a mixture of starting
material (8%), mono-tosylate (76%) and di-tosylate (16%) (LC area
%). Yield: 61% of intermediate 12.
Example A4a
[0102] Preparation of Intermediate 13 27
[0103] Solid sodium borohydride (2.50 g, 66 mmol) was added in
small portions within 15 min. into a magnetically stirred,
ice-cooled solution of (11R) and
(11S)-1-{[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]methyl}-8-fluo-
ro-5,11-dihydro-10H-dibenzo[a,d]cyclohepten-10-one (reaction
mixture of intermediate 7 and 8 before separation) (65:35, 1278 mg,
3.75 mmol) in isopropanol (160 mL) and 0.5 M phosphate buffer (pH
7, 63 mL). Reaction mixture was stirred at 0.degree. C. for
additional 15 min., quenched with saturated aqueous NH.sub.4Cl (30
mL); organic phase was separated, aqueous solution extracted with
ether (2.times.30 mL), combined organics washed with water
(2.times.50 mL), then brine (50 mL), dried (MgSO.sub.4), evaporated
in vacuo, to furnish crude mixture of two alcohols. HPLC separation
(Waters 515 pump, 2 mL injection loop, Merck Hibar.RTM.
250.times.25 mm column LiChrosorb.RTM. SI 60 7 .mu.m, Waters 2410
refractive index detector, EtOAc-hexane 30:70, 15 mL/min) gave pure
intermediate 13
(10S,11S)-11-{[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]methyl-
}-8-fluoro-10,11-dihydro-5H-diben-zo[a,d]cyclohepten-10-ol (449 mg,
1.31 mmol, 35%) as a colorless oil.
Example A4b
[0104] Preparation of Intermediate 14 28
[0105] A mixture of the alcohol (intermediate 13) (449 mg, 1.31
mmol), triethylamine (728 .mu.L, 530 mg, 5.24 mmol, 4 equiv.), DMAP
(160 mg, 1.31 mmol, 1 equiv.), and acetic anhydride (318 .mu.L, 343
mg, 3.36 mmol, 2.56 equiv) in dichloromethane (20 mL) was stirred
at room temperature under N.sub.2 for 2 h, then quenched with
saturated aqueous NH.sub.4Cl (12 mL), organic phase was separated,
aqueous solution extracted with CH.sub.2Cl.sub.2 (15 mL), combined
organics washed with water (2.times.20 mL), 0.5N HCl (10 mL), then
water (2.times.20 mL), dried (MgSO.sub.4) and evaporated in vacuo
to furnish crude intermediate 14
(10S,11S)-11-{([(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]methyl}-8-fluoro-10,1-
1-dihydro-5H-diben-zo[a,d]cyclohepten-10-yl acetate (478 mg, 1.24
mmol, 95%) as a yellowish oil, which was converted without further
purification.
Example A4c
[0106] Preparation of Intermediate 15 29
[0107] A mixture of acetal (intermediate 14) (478 mg, 1.24 mmol),
1N HCl (20 mL) and THF (20 mL) was stirred at room temperature
under N.sub.2 until starting material disappeared (ca. 6 h, TLC
control, EtOAc-hexane 80:20), then 25% aqueous K.sub.2CO.sub.3 (20
mL) was added, organic phase separated, aqueous solution extracted
with ether (2.times.15 mL), combined organics washed with water
(3.times.20 mL), dried (MgSO.sub.4) and evaporated in vacuo. Crude
product was purified by column chromatography (EtOAc-hexane 65:35)
to obtain intermediate 15
(10S,11S)-11-[(2R)-2,3-dihydroxypropyl]-8-fluoro-10,11-dihydro-5H-dibenzo-
[a,d]cyclohepten-10-yl acetate (389 mg, 1.13 mmol, 91%) as a
colorless oil.
Example A4d
[0108] Preparation of Intermediate 16 30
[0109] A mixture of the diol (intermediate 15) (389 mg, 1.13 mmol),
triethylanine (628 .mu.L, 457 mg, 4.52 mmol, 4 equiv.), DMAP (138
mg, 1.13 mmol, 1 equiv.), dibutyl(oxo)stannane (141 mg, 0.566 mmol,
0.5 equiv.), and tosyl chloride (431 mg, 2.26 mmol, 2.0 equiv) in
dichloromethane (20 mL) was stirred at room temperature under
N.sub.2 for 12 h, then quenched with saturated aqueous NH.sub.4Cl
(15 mL), organic phase was separated, aqueous solution extracted
with CH.sub.2Cl.sub.2 (2.times.15 mL), combined organics washed
with water (3.times.20 mL), filtered through 5 cm layer of
MgSO.sub.4, and evaporated in vacuo to furnish crude intermediate
16 (10S,11S)-8-fluoro-11-((2R)-2-hydroxy-3-{[(-
4-methylphenyl)sulfonyl]oxy}propyl)-10,11-dihydro-5H-dibenzo[a,d]cyclohept-
en-10-yl acetate (406 mg, 0.814 mmol, 72%) as a yellowish semisolid
mass, which was converted without further purification.
Example A5
[0110] Preparation of Intermediate 17 31
[0111] Intermediate 12 (prepared according to A3d) (0.15 g, 0.298
mmol) was dissolved in dry toluene. CH.sub.3SO.sub.3H (19 .mu.l,
0.149 mmol) was added and the reaction mixture was stirred at room
temperature for 30 min. Then Na.sub.2CO.sub.3 (sat. aq. sol.) was
added. After extracting 3 times with CH.sub.2Cl.sub.2 the combined
organic phases were dried with MgSO.sub.4. After removal of the
solvent, the residue was purified on silica gel column with
ether/hexane (50/50), which gave an yellowish oil. Yield: 0.11 g of
intermediate 17, 82%.
[0112] B. Preparation of the Final Compounds
Example B
[0113] Preparation of Compound 1 32
[0114] Intermediate 17 (prepared according to A5) (0.10 g, 0.228
mmol) was dissolved in THF (10 ml) and 40% CH.sub.3NH.sub.2 (10 ml)
was added. The solution was put in a tightly sealed steel vessel
and heated at 130.degree. C. for 12 hr. The reaction mixture was
cooled down to room temperature, NH.sub.4Cl (sat. aq. sol.) was
added. The reaction mixture was extracted 3 times with
CH.sub.2Cl.sub.2 and dried with MgSO.sub.4. After evaporation, the
residue was purified on silica gel column chromatography with
MeOH/CHCl.sub.3 (15/85), yielding a yellowish oil (60 mg of
compound 1, 88%).
[0115] Table 1 lists the compounds that were prepared according to
one of the above Examples.
2TABLE 1 Comp. Ex. No. No. Structure Physical data 1 B 33 2R, 3aR,
12bS: Mass spectrum: -CI m/z (assignment, relative intensity) 298
(MH.sup.+, 100%) -EI: m/z (assignment, relative intensity) 297
(M.sup.+., 3%), 279 (M.sup.+. --H.sub.2O, 6%), 248
(M.sup.+.--H.sub.2O--CH.sub.3NH.sub.2, 3%) -High resolution EI
Calculated C.sub.19H.sub.20FNO (M.sup.+.): 297.1529 Found: 297.1527
(100%) 2 B 34 .(+)-[R-(R*,R*)]-2, 3-dihydroxy butanedioate (1:1);
[2R-(2a, 3a.alpha., 12b.beta.)] 3 B 35 .(S)-Alpha-hydroxy
benzeneacetate (1:1); [2R-(2a, 3a.alpha., 12b.beta.)] 4 B 36 2S,
3aR, 12bS; 5 B 37 2S, 3aS, 12bR; 6 B 38 2R, 3aS, 12bR;
* * * * *