NZ280175A - Inhibiting testosterone 5alpha-reductase activity using an A ring modified 4-aza-3-oxo-cyclopentanoperhydrophenarthrene substituted in position-17beta by amino or acylamino - Google Patents

Abstract

A method of inhibiting testosterone 5alpha-reductase activity in a non-human animal is disclosed. The method comprises administering to the animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase of formula I, wherein the dotted line is an optional pi bond, R4 is hydrogen or methyl, R6 is hydrogen or C1-C3 saturated or unsaturated hydrocarbon, R7 is selected from the group consisting of hydrogen, C1-C6 alkyl, C1-C6 hydroxyalkyl, C1-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cyclopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs thereof, R17a is hydrogen or lower alkyl, and R17b is tertiary amino or tertiary amido. Also described is the use of compounds of formula I in the manufacture for inhibiting testosterone 5a-reductase activity.

Description

Divided from Patent Application No. 247598 filed on 11 May 1993 NEW ZEALAND PATENTS ACT, 1953 " OCT 1995 REceiSiT" No.: Date: COMPLETE SPECIFICATION INHIBITORS OF TESTOSTERONE 5 ALPHA-REDUCTASE ACTIVITY -+7We, ENDORECHERCHE INC., a corporation of Canada, of 2989 de la Promenade Ste-Foy, Quebec G1W 2J6, Canada hereby declare the invention for which -f"/ we pray that a patent may be granted to-fwe/us, and the method by which it is to be performed, to be particularly described in and by the following statement:- (followed by page la) $ jfj ~~y Jr=> '^-s w tt// l f il y %}; INHIBITORS OF TESTOSTERONE 5a-REDUCTASE ACTIVITY Field of the Invention This invention relates to medicinal uses of compounds disclosed herein for inhibiting testosterone 5a-reductase activity and to methods for the treatment of androgen-related diseases in non-human animals. The inhibitors disclosed have a good combination of inhibitory effect on 5a-reductase activity, low or no androgenic activity and, in some cases, antiandrogenic activity. More particularly, certain inhibitors are derivatives of 4-aza-androstanone or 4-aza androstenone.

The reader's attention is directed to our related New Zealand Specification number 247598 (hereafter NZ 247598) which describes and claims improved testosterone 5a-reductase inhibitors which more effectively inhibit testosterone 5 a-reductase. The teachings of NZ 247598 can be used to provide compounds that are testosterone 5a-reductase inhibitors and pharmaceutical compositions containing said compounds.

Background of the Invention Prior art inhibitors of 5a-reductase fail to provide an optimal combination of (1) lack of inherent androgenic activity and (2) ability to inhibit both of two different forms of testosterone 5a-reductase ("5a-reductase"). 5a-reductase is an enzyme which catalyzes the conversion of the androgen, testosterone, to the much more potent androgen dihydrotestosterone ("DHT"). DHT is the more active androgen in many target organs (Anderson and Liao. Nature 219:277-279, 1968). The same enzyme catalyzes the conversion of androstenedione into androstanedione.

Inhibitors of 5a-reductase inhibit biosynthesis of the products whose formation is catalyzed by 5a-reductase. 5a-reductase has been studied in different species (Liang et al. Endocrinology 117: 571-579, 1985). Its isolation and structure, and the INTELLECTUAL PROPERTY OTiCE OF N.Z. 2 6 FEB 2001 RECEIVED expression of cDNA encoding it have been described (Andersson and Russell. Proc. Natl. Acad. Sci. 87:3640-3644,1990).

Recent data have demonstrated the presence of at least two different genes expressing 5a-reductase in humans. Type I 5a-reductase (Andersson and Russell, Proc. Natl. Acad. Sci. 87, 3640-3644,1990) is expressed at a low level in the human prostate while type II 5a-reductase is the predominant enzyme isoform expressed in this tissue (Andersson et al., Nature 354, 159-161, 1991).

The blockade of 5a-reductase has been intensively studied in view of developing pharmaceutical drugs for the therapy of diseases, such as proctate cancer. In European Patent Appln. No. EP 285 383 Ramusson et al. disclose the treatment of prostatic carcinoma with 17£-N-monosubstituted-carbamoyl-4-aza-5cx-androst-l-en-3-ones). Diseases for which 5a-reductase inhibitors are also being studied include acne, baldness (Rittmaster et al. J. Clin. Endocrinol. Metab. 65:188-193,1987) and benign prostatic hyperplasia (Metcalf et al., TiPS 10: 491-495, 1989).

The 4-aza-steroid N,N-diethyl-4-methyl-3-oxo-4-aza-5a-androstane-17|3-carboxamide, 4-MA has proven useful in inhibiting the formation of DHT from testosterone in rat prostate in vitro and in vivo (Brooks et al. Endocrinology 109: 830-836, 1981), thus reducing the testosterone-induced increase in ventral prostate weight in these animals. Another 4-aza-steroid, MK-906 (PROSCAR), has been found to cause a reduction in the intraprostatic concentration of DHT and a 25-30% reduction in prostatic size in men (Imperato-McGinley et al., Proc. 71st Ann. meet. Endocr. Soc., p. 332, abst 1639,1989). However, Proscar is reported to be a potent inhibitor of the type II enzyme but a weak inhibitor of the type I enzyme (Andersson et al., Nature 354,159-161,1991). Such a low inhibitory potency on type I 5a-reductase probably explains why the highest doses of Proscar used in men generally fails to reduce serum dihydrotestosterone levels below 25 to 35% of control, thus leaving a highly significant concentration of circulating androgens (Vermeulen et al, The Prostate 14, 45-53, 1989). The inhibitory effect of the drug on prostatic volume in men remains limited at 25 to 35% over a period of 6 months (Stoner, J. Steroid Biochem. Mol. Biol. 37, 375-378, 1990). There is thus a need to develop compounds which can efficiently inhibit both type I and type II 5a-reductase and thus cause a more complete inhibition of circulating dihydrotestosterone levels.

In U.S. Patent Appln. No. 4,317,817, Belgian Patent Appln. No. 883 091 and British Patent Appln. No. 204 8888, Blohm and Metcalf discuss the use of certain diazo-steroids as steroid 5a-reductase inhibitors. Metcalf et al describe the synthesis of related compounds in Tetrahedron Lett. 21, 15-18, 1980.

In EP Publication No 343 954, EP Publication No 375 347, U.S. Patent Appln. No 4,882,319, U.S. Patent Appln. No 4,937,237 and J. Med. Chem. 33: 937-942, 1990, Holt et al. discuss the use of certain A-ring aryl steroid derivatives as steroid 5a-reductase inhibitors.

In EP Publication No 289 327 and Publication No 427 434, on one hand, and in J. Steroid Biochem. 34: 571-575, 1989 and Biochemistry 29: 2815-2824, 1990, on the other hand, Holt and Levy discuss, respectively, the use of androstene- and pregnene-3-carboxylate derivatives as steroid-5a-reductase inhibitors.

In EP Publication No 375 351, Holt et al. discuss the preparation of phosphoric acid substituted steroids as testosterone 5a-reductase inhibitors.

In EP Publication No 271 219, EP Publication No 314 199, and EP Publication No 155 096, Rasmusson and Reynolds discuss the preparation of 17fi-substituted-4-aza-5a-androstenones as steroid-5a-reductase inhibitors.

Brooks, et al. (Steroid 47: 1-19, 1986; Prostate 9: 65-76, 1986) have reported 5a-reductase inhibiting and androgen-blocking activities for some 4-aza-steroids.

Rasmusson et al. discuss certain aza-steroids as inhibitors of rat prostatic 5a-reductase (in J. Med. Chem. 27: 1690-1701, 1984; idem 29: 2298-2315,1986 and J. Biol. Chem. 259: 734-739,1984).

In EP Publication No 277 002, Holt et al. discuss 178-substituted-4-aza-5oc-androstane-3-ones.

In EP Publication No 271 220, Carlin et al. discuss the preparation of 17B-(N-monosubstituted carbamoyl)-4-aza-5a-andros^ane-3-ones.

In EP Publication No 200 859, Cainelli et al discuss the preparation of certain 4-aza-steroid derivatives which are stated to be steroidal 5a-reductase inhibitors.

In International Publication No WO 91/12261, Panzeri et al. discuss the preparation of 17p-substituted-4-aza-5a-androstan-3-one derivatives.

In U.S. 4396,615, Steroids 38:121-140,1981 and J. Steroid Biochem. 19: 1491-1502, 1983; Petrow et al discuss certain 6-methylene progesterone derivatives stated to be inhibitors of steroid 5a-reductase.

In U.S. 4,377,584 (see e.g., column 13), U.S. 4,220,775 and in EP Publication No, 414 490 and 414 491, Rasmusson et al. discuss certain 17fi-substituted-4-aza-5a-androstanones (including acyl amino substitutions) as steroid-5a-reductase inhibitors.

In EP Publication No 052799, Alig et al discuss the use of certain D-homosteroids as steroid 5a-reductase inhibitors.

In U.S. 4,191,759, Johnston and Arth discuss N-substituted-17£-carbamoyl-androst-4-en-3-ones as steroid 5a-reductase inhibitors.

In BE 855 992, Benson and Blohm discuss steroidal inhibitors of testosterone 5a-reductase, for treating skin disorders.

In CA 970 692, Voight and Hsia discuss compounds inhibiting 5a-reductase activity.

In FR 1 465 544, Jolly and Warnant discuss 4-aza-aromatic steroid derivatives as steroid 5a-reductase inhibitors.

In US 4,087,461, Robinson discuss certain allenic steroids as testosterone 5a-reductase inhibitors.

In EP Publication No 414 529, Metcalf discuss certain 17-substituted 10 steroidal acids as testosterone 5a-reductase inhibitors <see e.g. Abstract). See Also, Holt, et al., EP Publication No 427,434.

In EP Publication No 298 652, Bhattacharya disclose the synthesis of 4-aza-Al-steroids.

In U.S. Patent Appln. No 5,061,803 and 5,061,801, Williams discusses 15 a method for the synthesis of 17(3-alkanoyl-3-oxo-4-aza-5a-androst-l-enes and 3-oxo-4-aza-androst-l -ene 17p-ke tones.

In U.S. Patent Appln. No 5,061,802, Steinberg and Rasmusson discuss the preparation of 17|3-aminobenzoyl-4-aza-5a-androst-l-en-3-ones as benign prostatic hypertrophy agents.

Lan-Hargest et al. discuss the synthesis of bridged A ring steroids as 5a-reductase inhibitors (Tetrahedron Lett. 28:6117-6120, 1987).

Weintraub et al (in J. Med. Chem. 28: 831-833, 1985) discuss the preparation of 20-hydroxymethyl-4-methyl-4-aza-2-oxa-5a-pregnan-3-one as inhibitors of testosterone 5a-reductase.

Kadohama et al. (Cancer Res. 44: 4947-4954, 1984) discuss sodium 4-methyl-3-oxo-4-aza-5a-pregnane-20 (S) carboxylate inhibition of prostatic tumor 5a-reductase.

Maclndoe et al. in J. Steroid Biochem. 20, 1095-1100, 1984, discuss the 5a-reductase inhibiting effect, in MCF-7 human breast cancer cells and rat prostate, of certain 6-methylene steroids.

Liang et al (J. Biol. Chem. 256:7998-8005, 1981) discuss 17S-N,N-diethylcarboxyamoyl-4-methyl-4-aza-5a-androstan-3-one as a reversible inhibitor of 5a-reductase.

Salomons and Doorenbos (J. Pharm. Sci. 63:19-23,1974) and Doorenbos et al. (J. Pharm. Sci. 60:1234-1235,1971; idem 62:638-640,1973; Chem and Ind; 1322, 1970) discuss synthesis of 176 amino 4-aza- steroids.

Nakayama et al. (J. Antibiotics XLIL1221-1229, 1989; idem, 1230-1234, 1989; idem, 1235-1240, 1989) discuss the isolation of WS-9659 from Streptomyces and its inhibitory activity on testosterone 5a-reductase.

In EP Publication No 294 937 and EP Publication No 294 035, Nakai et al. discuss the preparation, respectively, of cinnamoyl amide derivatives and ((benzoylamino)phenoxy) butanoic acid derivatives, as inhibitors of 5a-reductase.

U.S. Patent 5,026,882 and EP Publication No 375 349 relates to certain steroid-3-phosphinic acid compounds for use as inhibitors of steroid 5a-reductase. These patents also summarize in their description of the related art, numerous compounds which are stated to be prior art 5a-reductase inhibitors. See, for example, Table I of U.S. Patent 5,026,882 and the discussion in the prior art section of the patent.

EP Publication No. 435 321 relates to A-nor-steroid-3-carboxylic acid derivatives, which reportedly exhibit 5a-reductase inhibition.

In International Publication No WO 91/13060 and EP Publication No 458 207, Okada et al. discuss the preparation of Indole derivatives as testosterone 5a-reductase inhibitors.

Salle, et al, "176-acylurea Derivatives of 4-Azasteroids as Inhibitors of Testosterone 5a-Reductase" relates to studies regarding the effectiveness on 5a-reductase of a new series of 17fi-acylurea substituted derivatives.

U.S. Patent 5,053,403 describes the use of certain androgen receptor 5 blocking agents together with certain 5a-reductase enzyme inhibitor in the treatment or prevention of sebaceous gland hypertrophy, hirsutism and male-pattern baldness.

Prior art inhibitors of 5a-reductase are not believed to fully inhibit both forms of 5a-reductase without exhibiting or causing undesirable androgenic 10 or other hormonal activity.

SUMMARY OF THE INVENTION During treatment of certain diseases whose progress is stimulated by the activation of androgen receptors, it is desirable to reduce activation of those receptors. This may be accomplished by reducing the availability of 5 "agonists", e.g., natural androgens and other compounds capable of activating the receptors or by reducing the availability of receptors and/or by blocking access to the receptors by compounds which would otherwise activate them. The latter function may be achieved by administering an "antagonist", a compound with affinity for a receptor which binds the receptor and blocks 10 access by agonists. In the case of androgen receptors, an androgen antagonist ("an antiandrogen") may desirably bind the androgen receptor without activating the receptor. Its physical presence blocks access to the receptor by natural or other androgens which, given access to the receptor, could bind and activate the receptor. 15 As disclosed herein/ novel testosterone 5a-reductase inhibitors are used in the treatment of androgen-sensitive diseases whose progress can be slowed by inhibiting activation of androgen receptors. Compounds of the invention described herein but claimed in NZ 247598 inhibit the activity of 5a-reductase which catalyzes the synthesis of the potent androgen, 20 dihydrotestosterone. Thus, availability of dihydrotestosterone to activate androgen receptors is desirably reduced.

It is important to achieve this desirable reduction of 5a-reductase activity without causing adverse effects on the ultimate goal of inhibiting activation of androgen receptors. Hence, even if a compound effectively 25 inhibits 5a-reductase activity, its therapeutic effect is reduced if the inhibitor itself has inherent androgenic properties such that the inhibitor activates the very receptors whose activation it is intended to reduce,—Likewise, the INTELLECTUAL PROPERTY inhibitor should resist being converted in vivo into an andipgerii€S£Offn<pe>iibnzl. 2 6 FEB 2001 RECEIVED Conversely, however, a 5a-reductase inhibitor having anfiandrogenic properties, displays two, rather than one, desirable effect on the treatment of androgen-related diseases. First, it inhibits enzymatic conversion of testosterone to dihydrotestosterone, thus reducing the amount of 5 dihydrotestosterone available to activate androgen receptors. Second, it antagonistically blocks androgen receptors, shielding them from activation by any available androgens, including any dihydrotestosterone which may have been synthesized in spite of the inhibitor.

Thus, inhibitors of 5a-reductase activity preferably display a 10 combination of desirable qualities, including (A) an ability to effectively inhibit 5a-reductase activity (preferably both types of 5a-reductase); and (B) a substantial lack of androgenic activity (and resistance to being converted in vivo into an androgen). It is also desirable that the inhibitors have antiandrogenic properties. In order to eliminate undesirable side effects, 15 preferred 5a-reductase inhibitors also substantially lack glucocorticoid characteristics.

It is, accordingly, an object of the invention described herein but claimed in NZ 247598 to provide improved 5a-reductase inhibitors which more effectively inhibit 5a-reductase activity, and preferably inhibit the activity of both known types of 20 human 5a-reductase, or to at least provide the public with a useful choice.

It is another object of the invention described herein but claimed in NZ 274598 to provide pharmaceutical compositions having 5a-reductase inhibitors possessing little intrinsic androgenic activity and little propensity to be converted in vivo to another compound possessing intrinsic androgenic activity, or to at least provide the public with a useful choice.

It is an object of the presently claimed invention to provide methods for the treatment of androgen-related diseases whose progress is aided by activation of androgen receptors or at least to provide the public with a diseases include, for example, prostate cancer, OFFICE OF N.Z. 2 6 FEB 2001 RECEIVED iU prostatic hyperplasia and sexual deviance and may be treated by the methods of reducing 5a-reductase activity provide herein.

Methods of human treatment are described which utilize 5a-reductase inhibitors of the invention, either alone or in combination with another active ingredient, e.g., an antiandrogen, as part of a combination therapy.

The foregoing and other objects may be achieved by providing pharmaceutical compositions described herein but claimed in NZ 247598'comprising the 5a-reductase inhibitors disclosed herein together with pharmaceutically acceptable carriers or diluents. Alternatively, the use of compounds of the invention described herein but claimed in NZ 247598 in the manufacture of medicaments may allow the foregoing and other objects to be achieved. These pharmaceutical compositions or medicaments are administered to a patient afflicted with a disease such as those discussed above, whose progress is aided by activation of androgen receptors.

One embodiment of the invention provides a ——; method of inhibiting testosterone 5a-reductase activity •' ..u i in a non-human animal in need of such inhibition, said method comprising administering to said animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: R4 R6 hydrocarbon; wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or Q-C3 saturate INTELLECTUAL PROPERTY d aPmfiEM 2 6 FEB 2001 RECEIVED o y •I i- ' • V3 a n u 11 wherein R7 is selected from the group consisting of hydrogen, CT-C6 alkyl, Cj-C6 hydroxyalkyl, Cj-Cg haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is hydrogen or lower alkyl; and wherein R17fi is tertiary amino or tertiary amido.

Another embodiment of the invention provides a method of inhibiting testosterone 5oc-reductase activity in a non-human animal in need of such inhibition, said method comprising administering to said animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: R4 R6 wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or Cj-03 saturated or unsaturated hydrocarbon; wherein R is selected from the group consisting of hydrogen, Cj-C6 alkyl, Cj-C6 hydroxyalkyl, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is selected from the group consisting of Cj-Cg alkyl, CT-C6 hydroxyalky, C|-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; and wherein R17fi is hydrogen, hydroxy or a hydroxy in vivo. moiety converted to INTELLECTUAL PROPERTY OFFICE OF N.Z. 2 6 FEB 2001 RECEIVED Another embodiment of the invention provides a ■ ——- method of inhibiting testosterone 5a-reducta$e activity in a non-human animal in need of such inhibition, said method comprising administering to said animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: R4 R6 wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a Cj-C3 saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, CrC6 alkyl, Cj-C6 hydroxyalkyl, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17<x is hydrogen or lower alkyl; and wherein R17fi is selected from the group consisting of acyl, carboxamide, tertiary amino and tertiary amidc^ Another embodiment of the invention provides a - method of inhibiting testosterone 5a-reductase activity in a non-human animal in need of such inhibition, said method comprising administering to said. animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: INTELLECTUAL PROPERTY OFFICE OF N.Z. 2 6 FEB 2001 RECEIVED r4 r6 wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or a Cj-Cg saturated or unsaturated hydrocarbon; n wherein R is selected from the group consisting of a C2-C6 alkyl, C2-C6 hydroxyalkyl, C2-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is hydrogen or lower alkyl; and wherein R172 is selected from the group consisting of acyl, carboxamide, tertiary amino and tertiary amido.

Another embodiment of the invention provides a method of inhibiting testosterone 5a-reductase activity in a human animal in need of such inhibition, said method comprising administering to said animal: a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: INTELLECTUAL PROPERTY OTICE OF N.Z. 2 6 FEB 2001 received wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is hydrogen or a Cj-C3 hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, a CrC6 alkyl, CrC6 hydroxyalkyl, CrC6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein Rg is selected from the group consisting of lower alkyl, cydoalkyl and a moiety which, together with R^ and the nitrogen atom depicted at R17fi, is a 5-7 membered heterocydic ring having a single nitrogen hetero atom; and wherein Rf, is selected from the group consisting of a moiety which, together with R-, and the nitrogen atom depicted at R17fi, is a 5-7 membered heterocyclic ring having a single nitrogen atom, -CORc, -CONR^, -CSNR^, -S02Rc, -P03RcRd(Rc and Rd being hydrogen, lower alkyl or lower haloalkyl).

Capsules having the 5a-reductase inhibitors discussed herein may also be utilized. The inhibitors and compositions containing them are utilized in accordance with the invention in methods for reducing 5a-reductase activity in non-human animals and in the treatment of diseases in non-human animals when progress is aided by activation of androgen receptors, e.g. prostate cancer, benign prostatic hyperplasia, acne, seborrhea, hirsutism, androgenic alopecia and the like.

Further embodiments of the invention provide for the use of the 5a-reductase inhibitors described herein in the manufacture of medicaments for inhibiting testosterone 5a-reductase activity.

Another embodiment of the present invention provides a use of an inhibitor of testosterone 5a-reductase having the molecular formula: R17« wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or C,-C3 saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, C,-C6 alkyl, C,-C6 hydroxyalkyl, CrC6 haloalkyl, C2-C6 carbonyalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17" is hydrogen or lower alkyl; and wherein RI7P is tertiary amino or tertiary amido; in the manufacture c for inhibiting testosterone 5a-reductase activity. 2 6 FEB 2001 received -15a- Another embodiment of the present invention provides a use of an inhibitor of testosterone 5a-reductase having the molecular formula: wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or C|-C3 saturated or unsaturated hvdrocarbon; wherein R/ is selected from the group consisting of hydrogen, Cj-C6 alkyl, Cj-Cg hydroxyalkyl, C^-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein RI7a is selected from the group consisting of C:-C6 alkyl, Cj-C6 hydroxyalky, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; and wherein Rl7fi is hydrogen, hydroxy or a moiety converted to hydroxy in vivo; in the manufacture of a medicament for inhibiting testosterone 5a-reductase activity.

INTELLECTUAL PROPERTY OFFICE OF N.Z. 2 6 FEB 2001 received t? ; C c -15b- Another embodiment of the present invention provides a use of an inhibitor of testosterone 5a-reductase having the molecular formula: R17« wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a C1-C3 saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, C1-C6 alkyl, Cj-C6 hydroxyalkyl, C1-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is hydrogen or lower alkyl; and wherein R172 is selected from the group consisting of acyl, carboxamide, tertiary amino and tertiary amido; in the manufacture of a medicament for inhibiting testosterone 5a-reductase activity.

INTELLECTUAL PROPERTY OFFICE OF N.Z. 2 6 FEB 2001 RECEIVED -15c- Another embodiment of the present invention provides a use of an inhibitor of testosterone 5a-reductase having the molecular formula: R4 R6 wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or a C1-C3 saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of a C2- C6 hydroxyalkyl, C2-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17tx is hydrogen or lower alkyl; and wherein R17S is selected from the group consisting of acyl, carboxamide, tertiary amino and tertiary amido; in the manufacture of a medicament for inhibiting testosterone 5a-reductase activity.

INTELLECTUAL PROPERTY OFFICE OF N.Z. 2 6 FEB 2001 RECEIVED -15d- Another embodiment of the present invention provides a use of an inhibitor of testosterone 5a-reductase having the molecular formula: wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is hydrogen or a Cj-C3 hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, a Cj-C6 alkyl, Cj-C6 hydroxyalkyl, Cj-Cg haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R-, is selected from the group consisting of lower alkyl, cydoalkyl and a moiety which, together with R^ and the nitrogen atom depicted at R1/fi, is a 5-7 membered heterocydic ring having a single nitrogen hetero atom; and wherein R^, is selected from the group consisting of a moiety which, together with R^ and the nitrogen atom depicted at R172, is a 5-7 membered heterocydic ring having a single nitrogen atom, -CORc, -CONR^, -CSNR^cj, -S02Rc, -P03RcRd(Rc and Rd being hydrogen, lower alkyl or lower haloalkyl); in the manufacture of a medicament for inhibiting testosterone 5a-reductase activity.

INTELLECTUAL PROPERTY OFFICE OF N.Z. 2 6 FEB 2001 RECEIVED DET AILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In some, but not all, embodiments, an azasteroidal nucleus has a substituent (i.e., other than hydrogen), on at least one of the 4, 6 or 7 positions, e.g., 4-methyl and/or 6-lower alkyl and/or 7-lower alkyl.

In some embodiments, the R17fi substituent is a tertiary amine such as -N(R19)(R20) where R19 is lower alkyl or haloalkyl, and R20 is lower alkyl. In other embodiments, R17P is a tertiary amido substituent, e.g., acylamino substituents such as -N(R25)C(0)R26, wherein R26 is hydrogen or a lower alkyl and R25 is a Cj-Cg saturated or unsaturated hydrocarbon such as cyclopropyl, cyclohexyl, butyl or isobutyl.

As used herein, the terms "tertiary amino" or "tertiary amido" refer to amino or amido substituents wherein the amino or amido nitrogen is not hydrogen substituted. Preferred substituents for the nitrogen include but are not limited to acyl and lower alkyl.

In order to avoid steric interaction between the R17a and R17fi, it is preferred that at least one of these two substituents be hydrogen, hydroxy or a substituent which is converted to hydroxy in vivo (e.g., benzoyloxy, acetoxy).

Hydrocarbon substituents may be saturated or unsaturated. Unsaturated substituents are believed to be especially useful at the R7 and R17a positions. In some embodiments, R7 is a C2-C6 alkyl, alkenyl or alkynyl substituent.

In some embodiments, especially when R17fi is hydrogen, hydroxyl (or an ester derivative thereof), R17a is Ct-C6 alkyl, Cj-Cg hydroxyalkyl, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 epoxyalkyl or an unsaturated analog of the foregoing. Preferred unsaturated analogs include, for example, halo or hydroxy alkynyl or alkenyl substituents, especially where the halo or hydroxy group is at the end of the substituent, i.e., farthest from the aza-steroidal D-ring. An unsaturation at the 1,2 or 3 position of the 17a substituent is also preferred.

Except where otherwise specified, substituents may have a or fi stereochemistry. Optional pi bonds denoted by dotted lines in a molecular 5 structure are independent of any other optional bonds appearing in that structure, the presence of one not being dependent on the presence or absence of another, unless valence requires interdependency. Compounds discussed herein may be formulated as salts thereof. Atoms of the azasteroidal nucleus for which no substituent is shown may optionally be further substituted (as 10 valence permits) so long as such substitution does not adversely affect the compound's ability to inhibit 5a-reductase activity, and does not render the compound substantially more androgenic.

As used herein, the term "lower" when describing a chemical moiety means a moiety having 8 or fewer atoms. For instance, a "lower alkyl" means 15 a Cj to Cg alkyl. Any moiety of more than two atoms may be straight- or branch-chained unless otherwise specified.

As discussed in more details below, carriers or diluents include solids and liquids. The novel pharmaceutical compositions of the invention described herein but claimed in NZ 247598 may be used in the treatment of androgen-related diseases. When administered 20 systemically by injection, e.g., for treatment of prostate cancer, benign prostatic hyperplasia, and other diseases not primarily effecting the skin, conventional diluents or carriers which are known in the art to be pharmaceutically acceptable for systemic use are used, e.g., saline, water, aqueous ethanol and oil. When the inhibitors are utilized for the treatment of androgen related diseases such as acne, seborrhea, hirsutism, androgenic alopecia, the inhibitors are preferably administered together with a conventional topical carrier or diluent such as a mivtiirp nf PfrVianol and propylene glycol. When used topically, it is preferred t INTELLECTUAL PROPERTY iat tfeiQ£h®n^sr 2 6 FEB 2001 RECEIVED carrier does not promote transdermal penetration of the active ingredients into the blood stream or other tissues where they might cause unwanted systemic effects. When a composition is prepared other than for immediate use, an art recognized preservative is typically included (e.g. benzyl alcohol).

When the compound is administered in a cutaneous or topical carrier the carrier may be any known carrier in the cosmetic and medical arts, e.g. any gel, cream, lotion, ointment, liquid or non liquid carrier, emulsifier, solvent, liquid diluent or other similar vehicle which does not exert deleterious effect on the skin or other living animal tissue. Examples of 10 suitable topical carriers include, but are not limited to liquid alcohols, liquid glycols, liquid polyalkylene glycols, water, liquid amides, liquid esters, liquid lanolin and lanolin derivatives and similar materials. Alcohols include mono and polyhydric alcohols, including ethanol, glycerol, sorbitol, isopropanol, diethylene glycol, propylene glycol, ethylene glycol, hexylene glycol, mannitol 15 and methoxyethanol. Typical carriers may also include ethers, e.g. diethyl and dipropyl ether, methoxypolyoxyethylenes, carbowaxes, polyethyleneglycerols, polyoxyethylenes and sorbitols. Usually, the topical carrier includes both water and alcohol in order to maximize the hydrophylic and lipophylic solubility. A typical carrier will comprise 75% ethanol or 20 isopropanol and 15% water.

The topical carrier may also include various ingredients commonly used in ointments and lotions and well known in the cosmetic and medical arts. For example, fragrances, antioxidants, perfumes, gelling agents, thickening agents such as carboxymethylcellulose, surfactants, stabilizers, 25 emollients, coloring agents and other similar agents may be present.

As illustrated by the examples which follow, the compositions of the described herein but claimed in NZ 247598 may contain well-known and curre form creams, lotions, gels and ointments which are acceptable and non toxic. The composition may be applied as a gel, a cream, an ointment, a lotion or the like.

A dry delivery system, as described in U.S. Patent Nos 3,742,951, 3,797,494 or 4,568,343 may be used.

Solvents or devices as described in U.S. Patent Nos 5,064,654,5,071,644 or 5,071,657 can also be used to facilitate transdermal penetration when systemic effects are desired.

The compound can also be administered by the oral route. The compound can be typically formulated with conventional pharmaceutical excipients.. e.g. spray dried lactose and magnesium stearate into tablets or capsules for oral administration. Of course, taste-improving substances can be added in the case of oral administration forms. When capsules for oral ingestion are desired, any pharmaceutical capsules known in the art may be filled with the 5a-reductase inhibitors of the invention, with or without additional diluents and other additives discussed herein.

The active substance can be worked into tablets or dragee cores by being mixed with solid, pulverulent carrier substances, such as sodium citrate, calcium carbonate or dicalcium phosphate, and binders such as polyvinyl pyrrolidone, gelatin or cellulose derivatives, possibly by adding also lubricants such as magnesium stearate, sodium lauryl sulfate, "Carbowax" or polyethylene glycol.

As further forms, one can use plug capsules, e.g. of hard gelatin, as well as closed solf-gelatin capsules comprising a softner or plasticizer, e.g. glycerine. The plug capsules contain the active substance preferably in the form of granulate, e.g. in mixture with fillers, such as lactose, saccharose, mannitol, starches, such as potato starch or amylopectin, cellulose d^i wa.IwtjspERTy or highly dispersed silicic acids. In solf-gelatin capsules, the active • 2 6 FEB 2001 RECEIVED is preferably dissolved or suspended in suitable liquids, such as vegetable oils or liquid polyethylene glycols.

The following non-limiting examples describe the preparation of a typical cream, lotion, gel and ointment, respectively. In addition to these vehicles, one skilled in the art may choose other vehicles in order to adapt to specific dermatologic needs.

EXAMPLE A. A typical lotion contains (W/W) 5% active compound, 15% propylene glycol and 75% ethanol and water 5%.

EXAMPLE B. A typical gel contains (W/W) 5% active compound, 5% propylene glycol, 0.2% Carbomer 940 (available as Carbopol 94QR from B.F. Goodrich), 40% water, 0.2% triethanolamine, 2% PPG-12-Buteh-16 (available as UconR fluid 50 from Union Carbide), 1% hydroxypropyl and 46.8% ethanol (95% ethanol-5% water).

EXAMPLE C. A typical ointment contains (W/W) 5% active compound, 13% propylene glycol, 79% petrolatum, 2.9% glycerylmonostearate and 0.1% polylparaben.

EXAMPLE D. A typical cream contains (W/W) 5% active compound, 0.2% propylparaben, 5% lanolin oil, 7.5% sesame oil, 5% cetyl alcohol, 2% glyceryl monostearate, 1% triethanolamine, 5% propylene glycol, 0.1% Carbomer 940R and 69.2% water.

The 5a-reductase inhibitors are preferably formulated into pharmaceutical compositions at conventional concentrations for 5a-reductase inhibitors. The attending clinician may elect to modify the concentration and/or dosage in order to adjust the dose to the particular response of each patient.

When 5a-reductase activity inhibitors are administered in accordance with the invention, they are preferably administered orally orpgrE^e^y^fRTY Dosage preferably ranges from about 1 mg to about 10C 0 mg (pfjrggtiyggi received expedient, i.e., 5a-reductase inhibitor(s), per day per 50 kg of body weight, most preferably from about 2.5 mg to about 500 mg per day per 50 kg of body weight.

Concentration of active expedient varies in a known manner depending 5 upon the method of administering the pharmaceutical composition. A composition suitable for oral administration may preferably include at least one inhibitor of 5a-reductase activity wherein the total concentration of all such inhibitors in said pharmaceutical composition is from about 1% to 95% of the composition (by weight), and preferably from about 5% to about 20%. 10 The pharmaceutical^ acceptable diluent is preferably starch or lactose (with or without tartrazine).

When prepared for parental injection, the inhibitor is preferably added at a concentration between about 2.0 mg/ml and about 50 mg/ml (preferably about 5.0 mg/ml to about 20 mg/ml) into a carrier preferably selected from 15 the group consisting of saline, water, aqueous ethanol and oil.

The pharmaceutical composition may be formulated for sustained release in accordance with known techniques. The sustained release formulations are preferably prepared in a known manner appropriate for either oral, intramuscular or 20 subcutaneous administration.

When the pharmaceutical composition is for topical use, the 5a-reductase inhibitor(s) is preferably formulated together with a carrier selected from the group consisting of propylene glycol, ethanol, isopropanol and water at a concentration ranging from 0.5% to 10% by total weight of the 25 pharmaceutical composition. The composition for topical use may be formulated, for example, as an ointment, a gel, a cream or a lotion, to be applied to affected areas of the skin in need of treatment OFFICE OF N.Z. 2 6 FEB 2001 RECEIVED In some embodiments of the invention described but not claimed, the 5a-reductase inhibitors are used in combination with another active ingredient as part of a combination therapy. For example, the novel inhibitors may be utilized together with a separate antiandrogen which may be incorporated into the same pharmaceutical composition as the 5a-reductase inhibitor, or which may be separately administered. An active compound may possess both antiandrogenic and 5a-reductase inhibiting activity, and may be supplemented with another compound to reinforce either or both of these activities (e.g., another antiandrogen or another inhibitor of 5a-reductase). Combination therapy could also include treatment with one or more compounds which inhibit the production of testosterone or its precursors.

When antiandrogen is used in a combination therapy in addition to the 5a-reductase inhibitors the antiandrogen may be, for example: OH CF3 Flutamide (systemic) EM 248 (topic) INTELLECTUAL PROPERTY OFFICE OF N.Z. 2 6 FEB 2001 received The antiandrogen is formulated at conventional concentrations and administered at conventional dosages, e.g., at the same concentrations and dosages set forth above for the 5a-reductase inhibitor.

The antiandrogen Flutamide is commercially available from Schering Corp. (New Jersey). The antiandrogen EM-248 may be synthesized as follows: OH c-c^oy^oTw if?5 f, EM 248 Compound b To a solution of testosterone I (288.43 g, 1.0 mole) in glacial acetic acid (3.5 L), ethanedi thiol (85 ml, 1.01 mole) and boron trifluoride (800 ml) were added at 10°C. The mixture was stirred at this temperature for 1 hour and poured over ice (2 kg). From this aqueous phase a white solid separated and was collected by filtration, washed with water (2x 2L) and air dried. Crystallization from methanol gave the pure compound b. Yield: 328.28 g (90%).

Compound c A solution of b (182.3 g, 0.5 mole) in dry dichloromethane (1.5 L) was added dropwise to a solution of pyridinium chlorochromate (150 g, 0.7 mole), molecular sieves 3A (200 g) and sodium acetate (25 g) at room temperature with mechanical stirring. After the addition was completed, the mixture was stirred for 16 hours and then diluted with diethyl ether (2 L) and filtered through silica gel in a fritted funnel. The filtrate was concentrated in vacuo and the resulting solid was crytallized from methanol to give the pure compound c. Yield: 158.7 g, (87%).

Compound d 2-(3- Butynyloxy)tetrahydro-2H-pyran (112.5 g, 0.729 mole) was added dropwise to a solution of methyllithium (500 ml of MeLi 1.4M in ether, .70 mole) in 1 L of anhydrous THF at -30 °C under argon atmosphere in a 5 L round bottom flask. After the addition was completed, the cooling bath was removed and the solution was allowed to stand at room temperature for 4 hours. The solution was cooled again at -30 °C and a solution of c (75 g, .207 mole) in 2.5 L of anhydrous THF was added dropwise. After the addition, the cooling bath was removed and the mixture was allowed to stand at room temperature for 16 hours. To this mixture,100 ml of brine was added and the solution was diluted with ethyl acetate washed with brine and dried with anhydrous MgS04. The solvent was evaporated and a solid crystallized after a short period of time. Hexane was added to complete the precipitation. The solid was then filtered and washed with hexane. The compound was used in the next step without further purification. Yield: 95.8 g (90%).

Compound e A mixture of compound d (30 g, .058 mole) and methyliodide (65 ml, 1 moie) in methanol 96% (750 ml) was heated under reflux for 16 hours. The solvent was then removed in vacuo and the crude mixture was diluted with ethyl acetate (1 L). The organic phase was washed with NaOH 3% (3 x 500 ml) and dried over MgS04. After the evaporation of the solvent the solid was washed with diethyl ether, filtered on a fritted funnel and washed again with diethyl ether. This compound can be used without further purification in the last step. Yield 65%. 17a-(chlorobutvnvl)-17B-hvdroxv 4-androsten-3-one (f, EM 248) A mixture of compound d (15 g, .04 mole), triphenylphosphine (21 g, .08 mole) and carbon tetrachloride (9.3, .06 mole) was heated under reflux in 1 L of anhydrous dichloromethane for 10 hours. After the evaporation of the solvent the crude mixture was adsorbed on silica gel and chromatographied on silica gel (flash) with diethyl ether:hexane (70:30). The compound was further purified by crystallization in diethyl ether. Yield 85%.

A combination therapy involving 5a-reductase inhibitor and antiandrogen has the beneficial effect of inhibiting activation of androgen receptors by two different mechanisms without significantly reducing testosterone levels, the reduction of which may cause undesirable side effects in some patients. In appropriate cases, i.e. where prostate cancer or another androgen related disease is not responding acceptably to treatment, a concurrent therapy designed to decrease testosterone levels may also be utilized (e.g., surgical or chemical castration, for example, by administering a LHRH agonists or antagonists known in the art).

Inhibitors of testosterone 5a-reductase of the formula: o CH3 include but are not limited to those set forth in Table I below: TABLE I Inhibitor Ri r3 5a-reductase inhibition Ki (nM) EM 316 ch3 H 29 EM 336 Cycio c3h5 H 11.2 EM 337 Cyclo C6Hn H 11.9 EM 347 C4H9 H 2.6 EM 401 c5h„ H 1.8 EM 402 c6h13 H 7.2 EM 405 Iso amyl H 2.2 EM 407 Ethylpropyl H .6 EM 422 ISO C4H9 H 7.3 EM 423 C3H7 H .1 EM 424 c4h9 ch3 11.8 EM 436 ch2c6h5 H .6 Testosterone 5a-reductase inhibitors of the formula: O rk J1 MHR2 include but are not limited to those set forth in Table II below: TABLE II Compound rl r2 5a-reductase inhibition Ki (nM) EM 373 Cycio c3h5 ch3 0.5 EM 374 Cyclo C3h5 c6h5 2.3 EM 390 Cyclo C3H5 C3H7 7.1 EM 392 Cyclo C3H5 c2h5 13.5 EM 394 Cyclo C3H5 C4H9 3.3 EM 396 Cyclo C3H5 IsoC3H7 14.0 EM 397 Cyclo C3H5 Cyclo C6Hn 3.2 EM 408 ch3 c6h5 8.2 Testosterone 5a-reductase inhibitors of the formula: include but are not limited to those set forth in Tables I and II as well as those . compounds set forth below in.Table HI.

TABLE m Compound Steroid nucleus R4 R° R7 r17° rITS EM 316 Nil ch3 H H H N(.CH,}CHO EM 336 NU ch3 H H H N(C3H5)CHO EM 337 Nil ch3 H H H N(C6Hu)CHO EM 347 Nil ch3 H H H N(C4H9)CHO EM 401 NU CHj H H H N(C5Hu)CHO EM 402 NU ch3 H H H N(C6H13)CHO EM 405 Nil ch3 H H H N(iso-ainyl)CHO EM 407 Nil ch3 H H H N(ethylpropvl)CHO EM 422 Nil n X uj.

H H ■ H N(iso-C4H9)CHO em 423 NU ch3 h h h N(C3H7)CHO em 424 NU ch3 h h h N(C4H9)CCX:H3 em 436 NU ch3 h h h N(CH2C5H5)CKO em 373 NU ch3 k h h N(Cycio-C3K5)CONHCH3 em 374 NU ch3 h h h N(CydoC3H5)CONHC6H5 em 350 NU ch3 h h h N(Cydo-C3H5)CONKC3H7 em 392 NU ch3 h k h N(Cydo-C3H5)CONHC2H5 em 394 NU ch3 H 1 H 1 t-i N"Cydo-C3K3!CONKC..H9 em 396 NU ch3 H H H N(Cydo-C3H3!CONK(Iso-C3H7) em 397 NU ch3 H H H N(CydoC3H;)CONH(Cydo-C6Kn) em 408 NU ch3 H H H N(CH3)CONHC6H3 em 409 NU ch3 H H H.

N(CH3)CONKCK3 em 322 NU ch3 H K C3hs OH em 441 NU H H H C3H5 OH em 378 NU ch3 H H c3h7 OH em 352 NU H H H c3h7 OH em 450 NU ch3 H H H N(C4H9)COCK;Cl em 314 A1 ch3 H H H N(CH3)CHO em 420 A1 ch3 H H H N(Cydo-C3K5)CONHC;K5 em 346 A1 H H H H N(CH3)CHO em 448 NU H H H C=C(CH,);I OH EM 465 Nil H H h CsC(CH2)Br OH.

EM 358 NU H H H C=C(CH2)3Br OH EM 471 NU H H h C=C(CH,)3r OH EM 321 NU ch3 H H .

C=C(CH2),Br OH EM 320 NU ch3 H H C=C(CH2)2r OH EM 501 NU • H H H CsC(CK2)2a OH EM 502 NU ch3 h h Csc;ch2;2ci OCOCsHs EM 503 NU ch3 h k CsC(CH2)2C j OH EM 543 NU ch3 ■ ch3 H H NCC.H^/CHO EM 561 NU ch3 h C.HgOH k NtCH^CHO EM 572 NU h. h H h ■ n'CC.h.j)C'OCK3 EM 591 NU CH3 h H h NCC.HjJ'SO-CK- EM 621 NU ck3 H H K n(ch9)p03(ch3)2 EM 435 NU ch3 H H -h N(ter-CsH,3)CHO Except where otherwise indicated, 5a-reductase inhibition is measured by the following method. Plates having 24 dishes per unit are used. Into each dish were placed 100,000 cells from the human carcinoma metastatic prostatic cell line DU 145 (ATCC # HTB 81) in MEM medium containing 2% dextran charcoal-treated calf serum, 1% penicillin, 1% streptomycin and 1% non essential amino acids. After 24 h, the medium was removed and replaced by 2.5 ml of MEM medium containing 2% dextran charcoal-treated calf serum, 10 nM of tritiated 4-androsten-3,20-dione and 1% of ethanol. Each dish had different concentrations of the 5a-reductase inhibitor being tested. The cells were incubated for 24 h at 37°C under an atmosphere of 5% C02 saturated with water. The extracellular medium was then removed, centrifuged at 1000 RPM for 10 min., and decanted in test tubes. To these test tubes was added 100 jil of ethanol containing 25 of androstaneaione, 25 yig of 4-androstenedione, 25 |ig of dihydrotestosterone and 25 jig of testosterone. The steroids were then extracted from the mixture by two extractions with 2 ml of diethyl ether. Phase separation was achieved by freezing of the aqueous phase. The organic phase was then evaporated, thus leaving a steroid residue which was dissolved in a few drops of methylene chloride and spotted on TLC plates (Whatman WH 4420222). After developing twice with a mixture of benzene-acetone (9:1), the spots were visualized by U.V. and gaseous iodine, cut, put into separate vials for each steroid and extracted for 15 min with 1 ml of ethanol. After addition of 10 ml of scintillation cocktail (NEN 989), the vials were shaked and counted.

The 5a-reductase activity is the sum of the transformation of 4-androstenedione to androstanedione and of the transformation of testosterone to dihydrotestosterone.

\ Conversion of tritiated 4-androsten-3,20-dione to other steroids in the presence of different concentrations of inhibitor and a constant concentration of radioactive 4-androstenedione is measured, and IC50 (i.e. the concentration of inhibitor required to inhibit 50% of 5a-reductase activity) values are then used to calculate Ki values of inhibition for each compound according to Cheng and Prusoff (Biochem. Pharmacol. 22, 3099-3108, 1973).

Set forth below are non-limiting examples of methods of synthesizing 5a-reductase inhibitors for use in the present invention. Those of skill in the art may readily alter these syntheses by known conventional techniques to produce other 5a-reductase inhibitors useful in carrying out the invention.

EXAMPLES OF SYNTHESIS OF PREFERRED INHIBITORS OF STEROID 5a-REDUCTASE ACTIVITY EXAMPLE 1 Preparation of 17p-(N-n-butyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, R-j=C4H9, EM 347) Synthesis described in scheme 1 Preparation of 17f$-hydroxy-5-oxo-A-nor-3,5-secoandrostan-3-oic Acid (1). To a stirred mixture of the testosterone acetate (Steraloids Inc. Wilton NH USA) (200 g, 0.605 mol) in ferf-butyl alcohol (2 L) was added a solution of sodium carbonate (96.3 g, 0.908 mol) in 460 mL of water. The mixture was brought to reflux and a solution of sodium periodate (893.8 g, 4.176 mol) and potassium permanganate (70.8 g, 0.448 mol) in warm water (75 °C) was added gradually (1 h) while the reflux temperature was maintained. The reaction was cooled to 30 °C, and after 15 min the solids were removed by filtration. The solid was washed with 800 mL of water, and the combined filtrates were concentrated under reduced pressure to remove most of terf-butvl alcohol (final volume 1.0 L). The aqueous residue was cooled with concentrated hydrogen chloride solution. The wwmtwpn RECEIVED extracted with methylene chloride (4 X 800 mL) and the combined organic phase was washed with water, dried and concentrated to solid. Thus the solid obtained was subjected to acetate hydrolysis by refluxing with NaOH (34.3 g, 0.857 mol) in methanol (2.0 L) for 12 h. The reaction mixture was concentrated to 400 mL, diluted with water (600 mL) and acidified to pH 3. The solid was filtered, washed with water and dried. The filtrate was extracted with methylene chloride (3 X 1.0 L), and the combined organic phases were concentrated to syrup. Both the precipitates and the syrup were swished with boiling EtOAc and cooled at 0 °C for overnight to give 125 g (67% yield) of colorless crystals; mp 205-207*C.

Preparation of 17(5-hydroxy-4-methyl-4-aza-androst-5-ene-3-one (3). In a Schlenk tube, MeNH2 was bubbled till saturation to a mixture of the seco acid 1 (8.0 g, 25.974 mmol) in ethylene glycol (80 mL) at room temperature. The clear yellowish solution was heated gradually (3 "C/min) up to 180 °C and held at this temperature for 1 h. The reaction mixture was cooled to 10 °C and water (80 mL) was added with stirring. The solid was filtered, washed with water (20 mL) and dried to give 6.1 g of 3 (81%); mp 181-183 °C.

Preparation of 17(3-hydroxy-4-methyl-4-aza-5a-androstan-3-one (5). A solution of the compound 3 (6 g, 20.7 mmol) in acetic acid (99.9%, 130 mL) was hydrogenated in the presence of platinium oxide (600 mg) at 45 p.s.i., starting at room temperature and heated to 60 °C over 12 h. The reaction mixture was cooled and filtered. The catalyst was washed with acetic acid (30 mL), and the combined filtrates were concentrated to a solid (5.5 g, 91%); mp 178-180'C. 4-Methyl-4-aza-5oc-androstan-3, 17-dione (7). The following method is the representative. To a stirred solution of compound 5 (7.3 g, 25 mmol) in methylene chloride (260 mL) was added pyridinium chlorochromate (8.1 g, 37 mmol) and the mixture was stirred at room temperature for 3 h. The contents were passed through Florisil (30-60 mesh) to remove the precipitates and the filtrates were washed with water (2 X 200 mL) and dried. The resulting residue was purified by flash column chromatography to give the dione 7 (4.4 g, 61%); mp 126-128'C.

Preparation of 17|3-(N-butyl)-amino-4-methyl-4-aza-5a-andro!ctar.-?-one w Rj=C4H9). The following method is representative. To a mixture of dione 7 (0.150 g, 0.495 mmol) and n-butylamine (0.040 g, 0. 54 mmol) in 1,2-dichloroethane was added sodium triacetoxyborohydride (0.156 g, 0.74 mmol) followed by acetic acid (0.03 g, 0.49 mmol) under argon at room temperature. After 16 h, the reaction mixture was diluted with methylene chloride (15 mL) and washed with 1 N aqueous sodium hydroxide (2 X 20 mL), followed by brine (20 mL), dried and solvent removed to give the crude product which was purified by flash column chromatography to provide the 17-N-butyl-derivative (0.110 g, 61 % yield).

Preparation of 17(5-(N-M-butyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, R1=C4H9, EM 347). To a solution of formic acid (0.026 g, 0.556 mmol) in chloroform (1.5 mL) was added dropwise dicyclohexylcarbodiimide (DCC) (0.114 g, 0.56 mmol) in chloroform (1.5 mL) at 0°C. After 5 min the above solution was added to the compound 9 (0.10 g, 0.28 mmol) in pyridine (2 mL). The mixture was then stirred for 1 hours at room temperature. Evaporation of solvent was followed by addition of ether gave dicyclohexylurea which was removed via filtration and the solid was washed with ether. The combined filtrate was concentrated and purified by flash column chromatography to give the product 11, (EM 347) (0.075 g, 70%); NMR (CDC13): 5 0.66 (s,3 H), 0.74-1.42 (m, 11 H), 1.2-2.08 (m, 19 H), 2.37-2.48 (m, 2 H), 2.87 (s, 3 H), 3.04 (dd, 1 H, J=4, 13 Hz), 3.2-3.4 (m, 3H), 8.12 (s, 0.8H), 8.24 (s, 0.2H); 13C NMR (CDCI3) 5 170.56, 164.54, 162.97, 68.59, 65.62, 51.99, 51.71, 44.11 ,36.85, 36.40, 34.12, 32.88, 30.64, 29.68, 29.04, 28.96, 25.20, 24.37, 22.86, 20.55, 20.21, 13.77, 12.34: . HRMS: calcd for C^H^N^, 388.3089; found 388.3147. t<n> z EXAMPLE 2 17P-(N-n-Amyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, R^CgHn, EM 401) This synthesis is described in scheme 1 Preparation of 17{5-(N-n amyl)-amino-4-methyl-4-aza-5a-androstan-3-one (9, Ri=C5Hu). To a mixture of dione 7 (3.4 g , 22.6 mmol) and n-pentylamine (L07 g, 12.3 mmol) in 1,2-dichloroethane was added sodium triacetoxyborohydride (3.5 g, 16.7 mmol) followed by acetic acid (0.68 g, 11.2 mmol) under argon at room temperature. After 16 h, the reaction mixture was diluted with methylene chloride (150 mL) and washed with 1 N aqueous sodium hydroxide (2 X 200 mL), followed by brine (200 mL), dried and solvent removed to give the crude product which was purified by flash column chromatography to provide the 17-N-n-amyl-derivative (2.5 g, 61 % yield).

Preparation of 17p(N-n-Amyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, R1=C5H11, EM 401). To a solution of formic acid (0.504 mL, 13.36 mmol) in chloroform (37 mL) was added dropwise dicyclohexylcarbodiimide (DCC) (2.75 g, 13.36 mmol) in chloroform (37 mL) at 0°C. After 5 min., the above solution was added to the compound 9 (2.5 g, 6.68 mmol) in pyridine (20 mL). The mixture was then stirred for 1 hours at room temperature. Evaporation of solvent was followed by addition of ether gave dicyclohexylurea which was removed via filtration and the solid was washed with ether. The combined filtrate was concentrated and purified by flash column chromatography to give the compound 11, R1=C5H11 (EM-401) (2.5 g, 93%) The NMR spectroscopy analysis gave a (4:1) mixture of two conformers, M. P. 149-151 *C; lH NMR (CDCI3): 8 0.67 (s ,3 H), 0.86 (s, 3 H), 0.82-1.19 (m, 6 H), 1.21-1.42 (m, 11 H), 1.56-1.57 (m, 2 H), 1.69-1.91 (m, 4 H), 1.92-1.97 (m, 3 H), 2.38-2.43 (m, 2 H), 2.89 (s, 3 H), 3.0 (dd, 1 H, /= 3.2,12.4 Hz), 3.21-3.28 (m, 3 H), 8.14 (s, 0.8 H), 8.2 (s, 0.2 H); 13C NMR (CDClg): 5 170 .56, 164 8, 162.97, 68.54, 65.58, 61.98, 51.93, 51.66, 51.24, 46.69, 44.28, 37.24, 36.8,36.37,34.07,32.83,32.12,29.64,29.13,29.04,28.8,28.19,25.15,24.33,23.22, 22.84,22.36,20.51,13.94,12.75,12.32; HRMS: calcd for C25H4202N2,402.3245, found 402.3242.

EXAMPLE 3 By analogous methods to those described in example 1, the following compounds were synthesized.

EM 316: 17(MN-methyl-N-fonnamido)-4-methyl-4-aza-5a-androstan-3-one (11, R^CHg). The product was prepared in 78% yield and the NMR spectroscopy analysis gave a mixture of two conformers, M.P. 194-196 °C; NMR (CDCI3): 8 0.74 (s, 2.4 H), 0.75 (s, 0.6 H), 0.88 (s, 0.6 H), 0.89 (s, 2.4 H), 0.78-1.14 (m, 3 h), 1.26-1.47 (m, 6 H ), 1.60-1.90 (m. 7 H); 2.01-2.07 (m, 2 H), 2.41-2.46 (m, 2 H), 2.90 (s, 3 H), 2.92 (s, 3 H), 3.02-3.07 (dd, 1 H, / = 12.58, 3.2 Hz), 3.32 (t, 0.8 H, J = 9.6 Hz), 4.21 (t, 0.2 H, J = 10 Hz), 8.15 (s, 0.8 H), 8.18 (s, 0.2 H); 13C NMR (CDCI3): 8 170.45,164.20,163.32, 68.95, 65.43, 61.36, 51.82, 51.37, 51.12, 45.50, 44.21, 37.10, 36.66, 36.26, 33.87, 33.58, 32.70, 29.59, 29.51, 28.92, 28.83, 25.04, 23.03, 22.84, 22.74, 21.49, 20.35,13.20,12.61,12.21; HRMS: calcd for C2lHMN202, 346.2620; found, 346.2645.

EM 336: 17(3-(N-Cyclopropyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, Rj= cyclo C3H5). The product was prepared in 74% yield and the NMR spectroscopy analysis gave a mixture of two conformers, M.P. 163-165 °C; !H NMR (CDC13): 8 0.39-0.44 (m, 0.4 H), 0.61-0.85 (m, 10 H), 0.86-1.17 (m, 2 H), 1.18-1.41 (m, 7 H), 1.42-1.56 (m, 1 H), 1.57-2.06 (m, 6 H), 2.35 (dd, / = 4.5, 9.4 Hz, 2 H), 2.38-2.54 (m, 2 H), 2.85 (s, 3 H), 2.97 (dd, / = 3.4, 12.5 Hz, 1H), 3.24 (t, / = 8.7, 8.9 Hz, 0.4 H), 4.0 (t, / = 9.2, 9.5 Hz, 0.6 H), 8.27 (s, 0.4 H), 8.33 (s, 0.6 H). 13C NMR (CDCI3): 8 170.6, 165.4, 163.5, 69.9, 65.6, 64.4, 51.9, 51.8, 51.3, 45.7, 44.2, 37.9,37.5, 36.4,34.2, 29.7, 29.3, 29.1, 29.0, 28.8, 25.3, 22.2, 20.7, 13.6, 12.3, 9.9, 8.1, 6.4, 6.2. HRMS: calcd for C^H^Np^ 372.2796; found 372.2820.

EM 337: 17(MN-Cyclohexyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, R1=cycloC6H11). The product was prepared in 52% yield and NMR spectroscopy analysis gave a (4:1) mixture of two conformers, M.P. 144-146 °C; NMR (CDCI3): 8 0.70 (s, 1.5 H), 0.77 (s, 1.5 H), 0.85 (s, 1.5 H), 0.87(s, 1.5 H), 0.81-1.41 (m, 12 H),1.44-1.83 (m, 13 H), 1.90-2.04 (m, 2 H), 2.40 (dd, ] = 4.6, 9.3 Hz, 2 H), 2.90 (s, 3 H), 2.99 (dd, / = 3.2, 12.4 Hz, 1 H), 3.16 (t, J = 9.7,9.9 Hz, 0.5 H), 3.70-3.82 (m, 0.5 H), 4.28 (t, J = 9.6, 9.9 Hz, 0.5 H), 8.30 (s, 0.5 H), 8.38 (s, 0.5 H). 13C NMR (CDCI3): 8 170.7, 163.5, 163.1, 77.2, 66.3, 65.7, 61.9, 55.4, 54.4, 52.4, 52.1, 51.4 44.7, 43.1, 37.2, 36.8, 36.5, 34.2, 34.1, 33.7, 32.9,30.9,30.6, 29.8,29.7,29.3,29.1,29.0, 27.9,26.9,26.2.. ?6.0,25.4,25.3,23.2, 22.9, 20.7,20.5, 13.0,12.6,12.4; HRMS: calcd for C26H42N202,414.3246 found 414.3270.

EM 402:17(3-(N-n-Hexyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, R1= C6H13). The product was prepared in 70 % yield. The NMR analysis gave a mixture of two conformers, M. P. 101-103 *C, XH NMR (CDCI3): 8 0.68 (s, 3 H), 0.86 (s, 3 H), 0.77-1.09 (m, 6 H), 1.22-1.42 (m, 10 H), 1.43-1.57 (m, 2 H), 1.60-1.82 (m, 5 H), 1.89-2.03 (m, 4 H), 2.38-2.43 (m, 2 H), 2.89 (s, 3 H), 2.97-3.03 (dd, 1 H, /=12.4,3.2 Hz), 3.18-3.28 (m, 2.4 H), 4.12 (t, 0.2 H, /=10 Hz), 8.14 (s, 0.8 H), 8.2 (s, 0.2 H); 13C NMR (CDCI3): 8 170.57,164.49,162.97, 68.55, 65.58, 61.99, 51.95, 51.66, 51.26, 46.72, 45.66, 44.32, 44.22, 37.24, 36.8, 36.37, 34.07, 32.83, 32.43, 31.32, 29.64, 29.19, 29.04, 28.95, 28.47, 26.64, 26.35, 25.15, 24.34, 23.23, 22.84, 22.49, 20.51, 13.92, 12.32; HRMS: calcd for C^H^O^, 416.3382, found, 416.3355.

EM 405:17(MN-iso-Amyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, Rj= iso-C5H1:l). The product was prepared in 66 % yield. The NMR analysis gave a (4:1) mixture of two conformers, M.P. 87-89 °C, !H NMR (CDClg): 8 0.67 (s, 3 H), 0.77-1.06 (m, 12 H), 1.21-1.57 (m, 10 H), 1.71-1.80 (m, 4 H), 1.82-1.97 (m, 3 H), 2.38-2.43 (m, 2 H), 2.89 (s, 3 H), 2.97-3.01 (dd, 1 H, /= 12.4, 3.2 Hz), 3.20-3.29 (m, 1.8 H), 4.16 (t, 0.2 H, /= 10 Hz), 8.13 (s, 0.8 H), 8.2 (s, 0.2 H); 13C NMR (CDCI3): 8 170.57, 164.46, 162.91, 68.49, 65.58, 51.92, 51.63, 44.19, 42.72, 37.19. 36.80, 36.35, 34.07, 32.81, 29.64, 29.19, 29.04, 28.93, 26.28, 25.92, 25.15, 24.27, 22.84, 22.43, 20.51, 12.77, 12.32; HRMS: calcd for C25H42°2N2' 402.3245, found, 402.3230.

EM 407:17p-(N-l-Ethylpropyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one ul, R=iso-C?H11). The product was prepared in 50 % yield and the NMR analysis gave a (2.33:1) mixture of two conformers, M.P. 111-113 °C, *H NMR (CDCI3): 8 0.74-1.2 (m, 15 H), 1.24-1.84 (m, 17 H), 1.95-2.1 (m, 2 H),2.41-2.42 (m, 2 H), 2.91 (s, 3 H), 2.99-3.1 (m, 1.7 H), 3.95 (t, 0.3 H, / = 10 Hz), 8.24 (s, 0.3 H), 8.48 (s, 0.7 H); 13C NMR (CDCI3): 8 170.60,163.88,163.46, 66.28, 65.74, 65.62, 63.81, 52.85, 52.02, 51.89, 51.77, 44.94, 43.17, 37.24, 36.39, 34.22, 32.89, 29.75, 29.66, 29.07, 29.01, 28.89, 28.56, 28.47, 26.19, 25.32, 25.22, 23.25, 23.05, 22.98, 20, 78, 20.57,13.25,13.07,12.36,11.79,11.44,10.62; HRMS: calcd for C25H4202N2, 402.3246, found 402.3265.

EM 422: 17[3-(N-iso-Butyl-N-formamido)-4-methyl-4-aza-5-androstan-3-one (11, R1=iso-C4H9). The product was prepared in 90 % yield and the NMR analysis gave a (4:1) mixture of two conformers, M.P. 52-54 "C, 1H NMR (CDCI3): 8 0.67 (s, 3 H), 0.85 (s, 3 H), 0.68-1.15 (m, 9 H), 1,21-1.38 (m, 6 H), 1.5-1.79 (m, 6 H), 1.81-1.99 (m, 3 H), 2.38-2.42 (m, 2 H), 2.88 (s, 3 H), 2.94-3.02 (dd, 1 H, / = 12.4, 3.3 Hz), 3.1-3.15 (dd, 0.2 H, J= 13.2, 5.7 Hz), 3.23 (t, 0.8, J =0.8 H), 3.32-3.39 (dd, 0.8 H, / =13.2, 6.6 Hz), 4.05 (t, 0.2 H, / =10 Hz), 8.15 (s, 0.2 H), 8.29 (s, 0.8 H); 13C NMR (CDC13): 8 170.57,164.66,162.82, 69.18, 65.57, 52.26, 51.89, 51.83, 51.23, 45.99, 44.25, 37.16, 36.34, 32.81, 29.04, 28.92, 28.03, 27.12, 26.76,25.12, 24.94,23.05,22.81,20.17,19.96,19.78,12.84,12.33; HRMS: calcd for C24H40N2O2, 388.3089, found, 388.3069.

EM 423:17fMN-n-propyl-N-formamido)-4-methyl-4-aza-5a-androstan-3-one (11, R1=C3H7). The product was prepared in 82 % yield and the NMR analysis gave a (4.5:1) mixture of two conformers, M.P. 127-129 °C; *H NMR (CDCI3) 8 0.65 (s, 3 H), 0.83 (s, 3 H), 0.69-1.13 (m, 6 H), 1.19-1.81 (m, 13 H), 1.86-2.0 (m, 3 H), 2.35-2.4 (m, 2 H), 2.86 (s, 3 H), 2.94-3.0 (dd, 1 H, ] = 12.4,3.2 Hz), 3.10-3.28 (m, 1.82 H ), 4.1 (t, 0.18 H, / =10 Hz), 8.11 (s, 0.82 H), 8.17 (s, 0.18 H); 13C NMR (CDCI3) 5 170.51,164.43,162.99, 68.51, 65.52, 51.89, 51.62, 48.30, 45.82, 44.17, 36, 32, 34.03, 32,78, 29.58, 28.98, 28.89, 25.11, 24.31, 22.78, 21.61, 20,47, 12.27, 11.24; HRMS: calcd for CjaH^Nj, 374.2933, found 374.2903.

EM-436: 17|5-(N-Benzyl-N-formamido)-4-methyl-4-aza-5<x-androstan-3-one (11, R1=CH2C6H5). The product was prepared in 80% yield. The NMR analysis gave a mixture of two conformers (4.88:1), m.p. 89-91°C, IR v cm"1 (KBr): 1640,1610; lH NMR (CDCI3): 8 0.74 (s, 3 H), 0.85 (s, 3 H), 2.37-2.42 (m, 2 H), 2.87 (s, 3 H), 2.95-3.0 (dd, 1 H, J=12.5, 3.4 Hz), 3.28 (t, 0.8 H, J=9.8 Hz), 4.18 (t, 0.2 H, J=9.7 Hz), 4.4 (d, 0.8 Ha, J=15.5 Hz), 4.5 (d, 0.4 H, J=3.8 Hz), 4.79 (d, 0.8 J=15.5 Hz), 7.1-7.3 (m, 5 H), 8.28 (s, 0.2 H), 8.42 (s, 0.8 H); 13C NMR (CDCI3): 8 170.38, 165.17, 162.93, 138.76, 137.38, 128.55, 128.34, 127.27,126.93,125.93,68.01,65.42,62.67,51.80,51.63,51.20,50.36,47.28,45.81, 44.11, 37.39, 37.06, 36.29, 34.04, 32.75, 29.61, 29.49, 28.87, 25.04, 24.65, 23.29, 22.72,20.54,12.95,12.41,12.23; HRMS: calcd for C^H^C^, 422.2933, found, 422.2924.

EXAMPLE 4 Preparation of 17j3-(N-methyl-N-formamido)-4-methyl-4-aza-5a-androst-l-ene-3-one (17) Preparation described in scheme 2 Preparation of 17|}-(N-methyl-N-fonnamido)-4-methyl-4-aza-5a-androst-l-ene-3-one (17, R1=CH3, EM 314). The following method is representative. Bis(trimethylsilyl)trifluoroacetamide (0.305 g, 1.185 mmol) was added to the mixture of formamide 11, R1=CH3 (EM 316) (0.10 g, 0.289 mmol) and 23-dichloro-5,6-dicyano-l,4-benzoquinone (0.066 g, 0.289 mmol) in dioxane (4 mL) under nitrogen. After 4 h at 25 °C, the contents were heated at 110 °C for 24 h. The resulting dark red solution was pour into the stirred mixture of methylene chloride (6 mL) and 1% aqueous sodium bisulphite solution (1.8 mL). The heterogeneous mixture was filtered. The dark red organic layer was washed with 2 mL of 2N HC1 followed by brine, dried and concentrated. The crude mixture was purified by column chromatography to give 41 mg of the product 17 R1=CH3 (EM 314) (41%); ]H NMR (CDCI3): 6 0.72 (s, 3H (78%)), 0.74 (s, 3H(22%)), 0.86-2.15 (m, 15H), 0.89 (s, 3H(22%)), 0.91 (s, 3H(78%)), 2.89 (s, 3H), 2.93 (s, 3H), 3.27-3.36 (m, 2H), 5.82-5.85(m, 3 H), 6,65 (d, 1H, J=ll Hz), 8.14-8.24 (m, 1H); HRMS: calcd for C21H32N202, 344.2463; found 344.2426.

SCHEME 2 RjN-CHO R=H 11 R=CH3 RJN-CHO 16 R=H 17 R^a^ 12 R=»H 13 R=CHj x 18 R=H 19 R=CH3, EXAMPLE 5 By analogous methods to those described in example 4, the compounds 16 (i.e. EM 346), 18 and 19 (i.e. EM 420) were synthesized using the formamide 10 or the ureas 12 and 13 as starting material. 28017 EXAMPLE 6 Preparation of 17(5-N-(lN-cydopropyl-2N-phenylurea)-4-methyl 4-aza-5a-androstan-3-one (13, R1=C3H5, R2=C6H5, EM 374 ) Preparation described in scheme 1 Preparation of 17p-N-(lN-cyclopropyl-2N-phenylurea)-4-methyl-4-aza-5a-androstan-3-one (13, R1=cyclo R2=C6H5, EM 374). The following method is representative. To a solution of compound 9 (R^ cyclo C3H5) (220 mg, 0.64 mmol) in THF (100 mL) was added N-methylmorpholine (0.107 mL, 0.975 mmol) followed by phenylisocyanate (0.1 mL, 0.9 mmol) at 0°C under argon. The mixture was stirred overnight at 0°C to room temperature. The mixture was diluted with ethyl acetate and washed twice with 2N HC1, dried and solvent removed to give the crude product which was purified by column to give the pure product 13 (EM 374) (210 mg, 73%); !H NMR (CDC13): 8 0.74-1.11 (m, 6H), 0.8 (s, 3 H), 0.86 (s, 3 H), 1.23-2.06 (m, 14H), 2.34-2.65 (m, 4H), 2.9 (s, 3 H), 2.99 (dd, 1 H, J=4, 13 Hz), 4.06 (t, 1H, J= 9.5 Hz), 7.0-7.42 (m, 5H); 13C NMR (CDClg): 8 170.72, 157.19, 139.09, 128.81, 122.77,119.49, 65.63,52.04,51.10,45.57, 38.08,36.35, 34.22, 32.79, 29.70, 29.02, 27.79, 25.244, 23.43, 23.05, 20.72,13.73, 12.35, 12.01, 9.96.

EXAMPLE 7 By analogous methods to those described in example 6, the following compounds were synthesized.

EM 373: 17j}-N-(lN-cyclopropyl-2N-methylurea)-4-methyl-4-aza-5a-androstan-3-one (13, R1=cyclo CjHg, R2=CH3). The product was prepared in 68% yield, lH NMR (CDCI3): 8 0.71 (s, 3 H), 0.82 (s, 3 H), 1.94-198 (dd, 1 H, / = 12.6, 3.4 Hz), 2.28-2.33 (m, 1 H), 2.35-2.40 (dd, 2 H, / = 9.5, 4.8 Hz), 2.5-2.55 (q, i H, / = 10.36 Hz), 2.76 (d, 3 H, / = 4.8 Hz), 2.87 (s. 3 H), 2.95-3.0! (dd, 1 H, / = 12.5, 3.4 Hz), 3.9 (t, 1 H, J = 10 Hz), 5.29 (q, 1 H, J=5 Hz); 13C NMR (CDCI3): 8 170.66, 160.86, 67.74, 65.58, 52.01, 51.05, 45.16, 37.98, 36.31, 34.16, 32.75, 29.66, 28.96, 27.37, 25.21, 23.32, 22.94, 20.68, 13.61, 12,29, 11.43, 9.51; MS: m e (% rel. int.) 344 (M+-57).

EM 392:17(3-N-(lN-cyclopropyl-2N-ethylurea)-4-methyl-4-aza-5a-androstan-3-one (13, R1=cyclo-C3H5/ R2=C2H5). The product was prepared in 78% yield, !H NMR (CDCy: 8 0.70 (s, 3 H), 0.81 (s, 3 H), 1.08 (t, 3 H, / = 7 Hz), 1.94 (dd, 1 H, / = 12.4, 3.2 Hz), 2.25-2.31 (m, 1H), 2.36 (dd, 1 H, / = 9.5, 4.8 Hz), 2.42-2.57 (q, 1 H, / =1 0 Hz), 2.86 (s, 3 H), 2.95-3.19 (dd, 1 H, / = 12.5,3.4 Hz), 3.20-3.23 (m, 2 H), 3.9 (t, 1 H, J = 10 Hz), 5.27 (t, 1 H, / = 5 Hz); 13C NMR (CDCI3) 8 170.60, 160.03, 67.50, 65.55, 51.95, 50.96, 45.31, 37.95, 36.26, 35.27, 34.10, 32.70, 29.61, 28.92, 27.18, 25.17, 23.28, 22.90, 20.64, 15.47, 13.58, 12.26, 11.64, 9.57; HRMS: calcd for C25H41N302, 415.319, found, 415.318.

EM 408: 17(i-N-(lN-methyl-2N-phenylurea)-4-methyl-4-aza-5a-androstan-3-one (13, R1=CH3, R2= C6H5). The product was obtained in 87 % yield, !H NMR (CDCy: 8 0.73 (s, 3 H), 0.86(s, 3 H), 2.4 (dd, 2 H, / = 9.5, 4.7 Hz), 2.90 (s, 3 H), 2.96 (s, 3 H), 2.96-3.0 (dd, 1 H, / = 12.5, 3.4 Hz), 4.24 (t, 1 H, / = 10 Hz), 6.53 (s, 1 H), 6.98 (t, 1 H, J = 7 Hz), 7.24 (t, 2 H, / = 7 Hz), 7.36 (d, 2 H, / = 7 Hz); 13C NMR (CDCI3): 5 170.66, 156.37, 139.24, 128.69, 122.70, 119.79, 65,55, 63.96, 51.92, 51.17, 44.91, 37.35, 36.34, 33.92, 32.75, 31.58, 29.66, 29.03, 28.95,25.19,23.11,20.50,13.10,12.30; HRMS: calcd for C27H39N302,437.2804, found, 437.2823. 7 EXAMPLE 8 Preparation of 17f5-N-(lN-cyclopropyl-2N-methylthiourea)-4-methyl-4-aza-5a-androstan-3-one (15, EM 379) The preparation is analogous to the preparation of compounds 13 in example 6 (see scheme 1), but using phenylisothiocyanate as reagent in the step converting compound 9 to compound 15.

/ EXAMPLE 9 Preparation of 17a-allyl-17P-hydroxy-4-methyl-4-aza-5a-androstan-3-one (21, R3=C3H5/ EM 322).

Preparation described in scheme 3 Preparation of 17a-allyl-17[3-hydroxy-4-methyl-4-aza-5a-androstan-3-one (21, R3=C3H5, EM 322). The following method is representative. To a solution of compound 7 (see scheme 1) (0.1 g, 0.328 mmol) in THF (10 mL) was added allylmagnesium bromide (394 pL, 0.394 mmol) at -78 °C. After addition the contents were stirred for 1 h and workup as usual to provide the crude product which was purified by column chromatography to give the pure product EM 322 (77 mg, 67 %); :H NMR (CDCl^: 8 0.68-1.0 (m, 2 H), 0.84 (s, 6 H), 1.14-1.66 (m, 11 H), 1.77-2.06 (m, 5 H), 2.14-2.2 (m, 1 H), 2.28-2.36 (m, 1 H), 2.42-2.48 (m, 2 H), 2.86 (s, 3 H), 2.94-2.99 (dd, 1 H, J=4,13 Hz), 5.14 (dd, 1 H, J=17,2 Hz), 5.2 (dd, 1 H, 13,2 Hz), 5.91-6.06 (m, 1 H); 13C NMR (CDCl^: 8 170.70, 134.85, 118.99, 82.13, 65.70, 51.91, 50.13, 46.33, 41.75, 36.45, 35.14, 34.78, 32.94, 31.63, 29.95, 29.03, 25.31, 23.55, 20.77, 14.55, 12.37; HRMS: calcd for C22H35N02, 345.2668; found, 345.2658. o □C CM CN ID CO W 2 w tn \ EXAMPLE 10 Preparation of 17a-propyl-17j}-hydroxy-4-inethyl-4-aza-5a-androstan-3-one (21, R3=C3H7, EM 378). Same preparation as the preparation of compounds 21 in example 9, but using propylmagnesium bromide instead of allylmagnesium bromide as reagent.

EXAMPLE 11 Preparation of 17a-allyl-17^-hydroxy-4-aza-5a-androstan-3-one (20, I^CjHy EM 441) Same preparation than the preparation of compounds 21 in example 9 in using the compound 6 as starting material .

EXAMPLE 12 Synthesis of 17a-(4-bromo-butynyl)-17[5-hydroxy-4-aza-5a-androstane-3-one (24, x=2, P=Br, EM 465) (scheme 4) Preparation described in scheme 1 and scheme 4 Preparation of 17P-hydroxy-4-aza-androst-5-ene-3-one (2). Referring first to sheme 1, in a pressure apparatus , NH3 was bubbled till saturation to a mixture of the seco acid 1 (6.0 g, 18 mmol) in ethylene glycol (60 mT.) at room temperature. The clear yellowish solution was heated gradually (3 °C/min) up to 180 °C and held at this temperature for 1 h. The reaction mixture was cooled to 10 °C and water (80 mL) was added with stirring. The solid was filtered, washed with water (20 mL) and dried to give 4.5 g of 2.

Preparation of 4-aza-5a-androstan-3,17-dione (6). A solution of the compound 2 (160 g, 0.5 mol) in acetic acid (500mL) was hydrogenated at 60 psi using Pt02 (15 g) as catalyst at 60 °C for 60 min After cooling and filtering, the catalyst was washed with acetic acid and the solvent removed. The residue dissolved in methylene chloride was washed with IN sulfuric acid, brine, saturated sodium bicarbonate, and brine. The organic phase was dried, filtered, and evaporated. The residue was chromatographed on silica gel. Elution with ethyl acetate/hexane gave crystalline compound which was treated with 3% methanolic sodium hydroxide solution at reflux for 90 min. After usual work up the obtained residue was dissolved in acetone (500 mL) cooled to 0°C and Jones' reagent was added (8N-chromic acid solution, 65 mL). After 15 min., isopropanol was added and the mixture was concentrated under vacuo. Water was added and the mixture was extracted with ethyl acetate. The organic layers were washed with brine, dried and evaporated to dryness. The chromatography on silica-gel of the residue with ethyl acetate / hexane as eluent gave the aza-ketone 6 (152 g) of which structure was determined by spectroscopic mean. 17a-(4-tetrahydropyranyloxy-butynyl)-17(i-hydroxy-4-aza-5a-androstan-3-one (22, x=2). Referring now to scheme 4, to anhydrous THF (140 mL) at -60 °C was added methyl lithium (1.4 M, 100 mL) and a solution of 4-tetrahydropyranyloxybutyne (21.6 g, 140 mmol).To this mixture warmed up to room temperature, stirred for 2h, and cooled to -60 °C was added dropwise a solution of above aza-ketone 6 (9.6 g, 30 mmol) in THF (350 mL), and the mixture was warmed up to room temperature and stirred for 16h. After usual work up, the compound 22 (x=2) was purified by silica-gel chromatography and its structure determined by spectroscopic mean. In a similar fashion, 17a-(4-tetrahydropyranyloxybutynyl)-17p-hydroxy-4-methyl-4-aza-5a-androstan-3-one (23, x=2) was prepared. 17a-(4-bromo-butynyl)-17P-hydroxy-4-aza-5a-androstane-3-one (24, P=Br, x=2, EM 465). To a solution of aza-diol 24, (P=OH) (179 mg, 0,5 mmol) obtained by acidic hydrolysis of the compound 22, and triphenylphosphine (262 mg, 1 mmol) in methylene chloride (15 mL) at 0°C was added CBr4 (249 mg, 1 mmol)and the mixture was stirred for 2h at room temperature, the solvent was removed and the compound 24 (P=Br, x=2 EM 465) was purified by flash silica-gel chromatography and this structure determined by spectroscopic mean. In a similar fashion, 17a-(4-bromo-butynyl)- 17(5-hydroxy-4-methyl-4-aza-5a-androstane-3-one (25, x=2, P=Br, EM 321) was prepared.

Preparation of 17a-(4-iodobutynyl)-17(5-hydroxy-4-methyl-4-aza-5a-androstan-3-one (25, x=2, P=I, EM 320). To a mixture of 17a-(4-bromobutynyl)-17(i-hydroxy-4-methyl-4-aza-5a-androstan-3-one (25, x=2, P=Br# EM 321) (200 mg, 0.471 mmol) in acetone (16 mL) was added sodium iodide (92 mg, 0.6132 mmol) and the mixture was refluxed for 12 h. Removal of acetone and usual workup provided the crude product which was purified by coiumn chromatography to give the pure product (EM 320) (137 mg, 60%); !H NMR (CDCLj): 5 0.83 (s, 3 H), 0.88 (s, 3 H), 2.41-2.46 (m, 2 H), 2.83 (t, 2 H, J=6.84 Hz), 2.91 (s, 3 H), 3.0-3.06 (dd, 1 H, J=3.4, 12.5 Hz), 3.24 (t, 2 H, J=7.1 Hz); HRMS: calcd for C^H^INC^, 483.1635; found, 483.1634.

SCHEME 4 11= -(CHg^THP 6 R=H 7 R=CH3 22 R=H 23 R=CH3 / OH '"=-(CH2)xP 24 R=H R=CH3 EXAMPLE 13 In a similar fashion, to Example 12, the following compounds described in Table IV are prepared using different tetrahydropyranyloxy-alkynes and different carbon tetrahalides.

TABLE IV ofv R R R' x P EM 501 h h 2 ci EM 502 ch3 coc6h5 2 ci EM 503 ch3 h 2 ci EM 448 h h 2 I EM 320 ch3 h 2 I EM 471 h h 3 I EM 358 h h 3 Br EXAMPLE 14 Preparation of 17p-(N-«-butyl-N-formamido)-4, 6-dimethyl-4-aza-5a-androstan-3-one (31, EM 548) Preparation described in Scheme 5.

Preparation of 17f3-acetoxy-6a-methyl -4-androsten-3-one (30). Testosterone (50 g) (Schering A.G. Germany) was treated in an apparatus equipped with a Uean-Stark, distillation apparatus, by diethylene glycol in toluene in the presence of a catalytic amount of p-toluenesulfonic acid at reflux for 16h. The resulting ketal 26 was oxidized by monoperoxyphtalic acid, magnesium salt (Aldrich Chem. Comp, Inc. Milwaukee Wis USA) in iso-propanol at 50 °C for lh. After removal of the solvent and crystallization the mixture of epoxyde 27 was heated at reflux with large excess methyl magnesium iodide in tetrahydrofuran for 18h. The 6|5-methyl ketal 28 was deprotected by standing overnight at room temperature with a mixture of acetone / water (9:1). The hydroxy ketone 29 thus obtained was mono dehydrated by heating in a mixture of 0.1 N sodium hydroxide in methanol and the 17p-hydroxyl was acetylated by usual manner (acetic anhydride / pyridine).The 6-methyl enone 30 was thus obtained (27 g) and characterized by spectroscopy. 17(5-(N-n-butyl-N-formamido)-4, 6-dimethyl-4-aza-5a-androstan-3-one (31, EM 548). The 6-methyl enone 30 is transformed into 17p-(N-n-butyl-N-formamido)-4,6-dimethyl-4-aza-5a-androstan-3-one (31, EM 548) by a process analogous to the process described in the example 1 for conversion of compound testosterone acetate to compound 11.

SCHEME 5 31 EXAMPLE 15 Preparation of 17[MN-alkyl-N-formamido)-4-methyl-7a-hydroxyalkyl-4-aza-5a-androstan-3-one (34) Synthesis is described in scheme 6 The following method is representative. The commercial 17p-acetoxy-4, 6-androstadien-3-one 32 (Steraloids Inc. Wilton, NH, USA) is treated by an 1.5 excess ot TBDMSO(CH2)xCu(CN)Li (prepared from TBDMSO(OH2)xI ,t-BuLi and CuCN) in ether and tetrahydrofuran in presence of trimethylsilyl chloride at -78 °C. The mixture is heated to room temperature and usual work up is made. The resulting compound 33 is transformed into 17(5-(N-alkyl-N-formamido)-4-methyl-7a-hydroxyalkyl-4-aza-5a-androstan-3-one (34) by a process similar to the process described in the example 1. The last step is the deprotection of the silyl group.

SCHEME 6 / 34 EXAMPLE 16 Preparation of alkylamide, alkylsulfamide and alkylphosphite derivatives of 17P-N-alkyl-4-methyl-4-aza-5a-androstan-3-one Synthesis is described in scheme 7 The compounds 8 or 9 prepared in accordance with scheme 1 are treated at room temperature by acyl chloride in tetrahydrofuran using a 2 fold excess of K2C03 powder as base. After usual work up, the compounds 35 or 36 are obtained. The use of sulfonyi chloride instead of acyl chloride gives in the same conditions respectively the compounds 37 or 38, and the use of dialkyl chloro phosphate gives respectively the compounds 39 or 40.

EM 424: 17(3-(N-n-butyl-N-acetamido)-4-methyl-4-aza-5a-androstan-3-one.

The product was prepared in 85 % yield. The NMR analysis gave a (1.85:1) mixture of two conformers, M.P. 152-154 °C, !H NMR (CDCI3): 8 0.67 (s, 1.95 H), 0.74 (s, 1.05 H), 0.80-1.0 (m, 9 H), 1.07-1.69 (m, 12 H), 1.71-1.91 (m, 5 H), 1.99-2.07 (m, 1 H), 2.12 (s, 1.05 H), 2.14 (s, 1.95 H), 2.42-2.45 (m, 2 H), 2.84-3.0 (m, 0.35 H), 2.91 (s, 3 H), 3.0-3.05 (dd, 1 H, /= 12.3,3.2 Hz), 3.11-3.18 (m, 0.65 H), 2.24-2.29 (m, 0.65 H), 3.68-3.71 (m, 0.7 H), 4.49 (t, 0.65 H, / = 9.9 Hz); 13C NMR (CDCI3): 8 171.43,171.14,170.54, 67.29, 65.53, 62.27, 51,05,46, 36,45.55, 44.55, 44.34, 37.10, 36.31, 33.96, 33.01, 32.75, 30.87, 29.67, 29.22, 28.98, 28.94, 25.18, 24.59, 23.65, 23.17, 22.70, 22.33, 20.49, 20.34, 20.04, 13.66, 12.94, 12.73, 12.29; HRMS: calcd for C25H42N202, 402.3246, found, 402.3234.

SCHEME 7 Additional examples of pharmaceutical compositions are set forth below: EXAMPLE 17 - Composition suitable for injection Ingredient % by Weight of Total Composition EM 378 (a 5a-reductase inhibitor) 0.4 Ethanol 6.4 NaCl 0.8 Water 91.5 Benzyl alcohol 0.9 EXAMPLE 18 - Topical lotion Ingredient % by Weight of Total Composition EM 402 (a 5a-reductase inhibitor) .0 Ethanol 47.5 Propylene glycol 47.5 EXAMPLE 19 - A tablet Ingredient % by Weight of Total Composition EM 378 (a 5a-reductase inhibitor) 46.5 Flutamide (an antiandrogen available from Schering Corp., New Jersey) 46.5 Gelatin 2.0 Lactose 2.5 Starch 2.5 1 EXAMPLE 20 - A topical lotion Ingredient % by Weight of Total Composition EM 402 (a 5a-reductase inhibitor) .0 EM 248 (an antiandrogen) .0 Ethanol r 45.0 Propylene glycol 45.0 The terms and descriptions used herein are preferred embodiments set forth by way of illustration only, and are not intended as limitations on the many variations which those of skill in the art will recognize to be possible in practicing the present invention as defined by the claims.

Claims (32)

WHAT WE CLAIM IS:

1. A method of inhibiting testosterone 5a-reductase activity in a non-human animal in need of such inhibition, said method comprising administering to said animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: R17<x wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or saturated or unsaturated hydrocarbon; wherein R is selected from the group consisting of hydrogen, Cj-C6 alkyl, Cj-Cg hydroxyalkyl, Cj-Cg haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is hydrogen or lower alkyl; and wherein R17fi is tertiary amino or tertiary amido.

2. The method of claim 1 wherein said inhibitor is administered by topical application to the skin.

3. The method of claim 2 wherein said animal is afflicted with a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease. "^t^ormce'AofP't?zERTY 2 6 FEB 2001 RECEIVED - 68 -

4. A method of inhibiting testosterone 5a-reductase activity in a non-human animal in need of such inhibition, said method comprising administering to said animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or C1-C3 saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, CrC6 alkyl, C1-C6 hydroxyalkyl, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is selected from the group consisting of Cj-Cg alkyl, Cj-C6 hydroxyalky, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; and wherein R17fi is hydrogen, hydroxy or a moiety converted to hydroxy in vivo.

5. The method of claim 4 whei administered by topical application to the skin. intellectual j>j20perty ein smIe lOPiRifor is 2 6 FEB 2001 received - 69 -

6. The method of claim 5 wherein said animal is afflicted with a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease.

7. A method of inhibiting testosterone 5a-reductase activity -human animal in need of such inhibition, said method comprising administering to said animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: R17« wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a C1-C3 saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, Cj-C6 alkyl, Cj-Cg hydroxyalkyl, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is hydrogen or lower alkyl; and wherein R17fi is selected from the group carboxamide, tertiary amino and tertiary amido. office of n.z. 2 6 FEB 2001 received - 70 -

8. The method of claim 7 wherein said inhibitor is administered by topical application to the skin.

9. The method of claim 8 wherein said animal is afflicted with a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease.

10. A method of inhibiting testosterone 5a-reductase activity in a in a non-human animal in need of such inhibition, said method comprising administering to said animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: R17« wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or a C1-C3 saturated or unsaturated hydrocarbon; n wherein R is selected from the group consisting of a C2- C6 hydroxyalkyl, C2-C6 haloalkyl, C2-C6 carbonylalkyl r- o 11 i J 1 £U IN-TELLECTUAL PROPERTY C3-C6 epoxyalkyl and unsaturated analogs of tl te fo^^pgfp N z wherein R17a is hydrogen or lower alkyl; and 2 6 FEB 2001 received wherein R178 is selected from the group consisting of acyl, carboxamide, tertiary amino and tertiary amido.

11. The method of claim 10 wherein said inhibitor is administered by topical application to the skin.

12. The method of claim 11 wherein said animal: is afflicted with a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease.

13. A method of inhibiting testosterone 5a-reductase activity in a non-human animal in need of such inhibition, said method comprising administering to said animal a therapeutically effective amount of an inhibitor of testosterone 5a-reductase having the molecular formula: wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is hydrogen or a Q-C3 hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, a Q-C alkyl, C^-Cg hydroxyalkyl, CT-C6 haloalkyl, C2-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated an; loss?w§r?ffitns; RECEIVED - 72 - wherein Rj is selected from the group consisting of lower alkyl, cycloalkyl and a moiety which, together with R^, and the nitrogen atom depicted at R178, is a 5-7 membered heterocyclic ring having a single nitrogen hetero atom; and wherein Rb is selected from the group consisting of a moiety which, together with Rg and the nitrogen atom depicted at R17fi, is a 5-7 membered heterocyclic ring having a single nitrogen atom, -CORc, -CONR^, -CSNRcRd, -S02Rc, -P03RcRd(Rc and Rd being hydrogen, lower alkyl or lower haloalkyl).

14. The method of claim 13 wherein said inhibitor is administered by topical application to the skin.

15. The method of claim 14 wherein said animal is afflicted with a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease.

16. A method according to any one of claims 1 to 15 of inhibiting testosterone 5a-reductase activity comprising administering to a non-human animal in need of such treatment a therapeutically effective amount of the 5a-reductase inhibitor substantially as herein described with reference to any example thereof. intellectual property office of n.z. 2 6 FEB 2001 received -73 -

17 A use of an inhibitor of testosterone 5a-reductase having the molecular formula: R4 R6 wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or Cj-C3 saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, CT-C6 alkyl, C1-C6 hydroxyalkyl, CT-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is hydrogen or lower alkyl; and wherein R17fi is tertiary amino or tertiary amido; in the manufacture of a medicament for inhibiting testosterone 5a-reductase activity. .

18. A use of claim 17 wherein said inhibitor is administered by topical application to the skin.

19. A use of claim 18 to treat a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatmprn- nf said skin disease. intellectual property office of n.7- 2 6 FEB 2001 received -74-

20. A use of an inhibitor of testosterone 5a-reductase having the molecular formula: wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or C1-C3 saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, Cj-Cg alkyl, Cj-C6 hydroxyalkyl, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is selected from the group consisting of Cj-C6 alkyl, Cj-C6 hydroxyalky, CT-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; and wherein R178 is hydrogen, hydroxy or a moiety converted to hydroxy in vivo; in the manufacture of a medicament for inhibiting testosterone 5a-reductase activity.

21. A use of claim 20 wherein administered by topical application to the skin. intellectual property saidPFfMhibitots.zis 2 6 FEB 2001 RECEIVED -75-

22. A use of claim 21 to treat a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease.

23. A use of an inhibitor of testosterone 5a-reductase having the molecular formula: wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a Cj-Gj saturated or unsaturated hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, C}-C6 alkyl, C|-C6 hydroxyalkyl, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; wherein R17a is hydrogen or lower alkyl; and wherein R17g is selected from the group carboxamide, tertiary amino and tertiary amido; in the manufacture of a medicament for inhibiting testosterone: > a-re^uctase"activity. received office of n.z. -76-

- - 24. A use of claim 23 wherein said inhibitor is administered by topical application to the skin.

25. A use of claim 24 to treat a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease.

26. ^ use °f 311 inhibitor of testosterone 5a-reductase having the moleculai formula: R4 R6 wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is a hydrogen or a saturated or unsaturated u j u intellectual prope hydrocarbon; office of n.z. wherein R is selected from the group consisting of i 2 6 FEB $301 C6 hydroxyalkyl, C2-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the wherein R17a is hydrogen or lower alkyl; and received forggomg; -77- wherein R17S is selected from the group consisting of acyl, carboxamide, tertiary amino and tertiary amido; in the manufacture of a medicament for inhibiting testosterone 5a-reductase activity. •

27. A use of claim 26 wherein said inhibitor is administered by topical application to the skin.

28. A use of claim 27 to treat a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease.

29. A use of an inhibitor of testosterone 5a-reductase having the molecular formula: intellectual property office of n.z. 2 6 FEB 2001 RECEIVED wherein the dotted line is an optional pi bond; wherein R4 is hydrogen or methyl; wherein R6 is hydrogen or a CJ-C3 hydrocarbon; wherein R7 is selected from the group consisting of hydrogen, a C|-C6 alkyl, Cj-Cg hydroxyalkyl, Cj-C6 haloalkyl, C2-C6 carbonylalkyl, C3-C6 cydopropylalkyl, C3-C6 epoxyalkyl and unsaturated analogs of the foregoing; -78- wherein Rg is selected from the group consisting of lower alkyl, cycloalkyl and a moiety which, together with and the nitrogen atom depicted at R178, is a 5-7 membered heterocyclic ring having a single nitrogen hetero atom; and wherein R^, is selected from the group consisting of a moiety which, together with R., and the nitrogen atom depicted at R17S, is a 5-7 membered heterocyclic ring having a single nitrogen atom, -CORc, -CONR^d, -CSNR^j, -S02Rc, -P03RcRd(Rc and Rd being hydrogen, lower alkyl or lower haloalkyl); in the manufacture of a medicament for inhibiting testosterone 5a-reductase activity.

30. A use of claim 29 wherein said inhibitor is administered by topical application to the skin.

31. A use of claim 30 to treat a skin disease whose progress is aided by activation of androgen receptors, and wherein said topical application is for the treatment of said skin disease.

32. A use of any one of claims 17 to 31 substantially as herein described with reference to any example thereof. intellectual property office of N.Z. 2 6 FEB 2001 received END