NO140104B - ANALOGICAL PROCEDURE FOR THE PREPARATION OF 17BETA-HYDROXY-16,16-DIMETHYLESTR-4-EN-3-ON WITH THERAPEUTIC ACTIVITY - Google Patents

Description

The present invention relates to the production of 17 8-hydroxy-16,16-dimethylestr-4-en-3-one with the formula:

which has an antiandrogenic effect and the ability to suppress the secretion of sebum.

This antiandrogenic effect of this steroid compound

The solution is remarkable because the corresponding 16-monomethyl-steroid, a compound produced several years ago and which be-

written in Example 7 of US Patent 3,049,555, has the opposite biological effect: the compound is androgenic. The monomethyl steroid also promotes anabolism, a potentially complicating side effect that the dimethyl steroid produced according to the invention is not burdened with. Androgenic and anabolic action likewise yields another steroid which, were it not for an unexpected difference in activity, might be considered closely related, namely the compound 17'0-nydroxyspiro[cyclopropane-1,16'-estr-4-ene]- 3'-one, which is described in example 9 of US patent 3,280,156.

In the table below are the results of standardized tests for the detection of anabolic and androgenic activity,

and shows the unexpected absence of such an effect, which distinguishes 17g-hydroxy-16,16-dimethylestr-4-en-3-one. The procedure was essentially as described by Saunders and Drill, Proe. Soc.

Exp. Biol. Med., 94, 646 (1957). Male rats of the species Badger were castrated at the age of 22 to 24 days, and each group of 5 or more animals was given, 19-21 days later, the test compound in question dissolved or suspended in corn oil by intramuscular administration in equal doses distributed over 7 consecutive days. Typically, the first total intramuscular dose was 5 mg of compound in 0.7 ml of corn oil. Another group of 5 or more animals given corn oil alone in the same manner served as control samples. One day after the end of the treatment, the animals were sacrificed and (1) the seminal vesicles and ventral prostate glands and (2) the levator ani muscle were dissected free of adjacent tissue. Fluid was squeezed from the bladders (but not the prostate or the muscles), after which the bladders and muscles were dried and weighed. A compound is considered androgenic if the mean weight of the bladders in the group of animals treated is significantly greater (P to 0.01) than the corresponding weight for the control group, and when there is a proportional increase in the mean prostate weight of treated animals vis-a-vis control animals. A compound is anabolic if the mean weight of the levator ani muscles of the group of treated animals is significantly greater (P > 0.01) than the corresponding weight of the control group. Compounds that are found to be active are tested again at ever smaller doses to determine the degree of effectiveness. In the table, the compound 170-hydroxy-16,16-dimethylestr-4-en-3-one is called "dimethyl", "monomethyl" refers to 17g-hydroxy-160-methyl-estr-4-en-3-one and "cyclopropyl" refers to 17<1>g-hydroxy-spiro[cyclopropane-1,16<1->estr-4-ene]-3'-one. Each steroid was administered intramuscularly. continued, of table

The antiandrogenic utility of 17Ø-hydroxy-16,16-dimethylestr-4-en-3-one is evident from the results of an experiment which involved inhibiting testosterone-stimulated growth of the seminal vesicles and prostate glands in castrated immature male rats. The procedure is as follows: 20 male rats of the Charles River strain are castrated at the age of 22 days and divided into two equal groups so that each animal in each group has its control animal in the other." When the rats are 36 days old, a mixture of 8 mg of testosterone is implanted , 8 mg "Carbowax" (polyethylene glycol), and 16 mg "Flexo Wax C Light" (non-crystalline hydrocarbon wax with melting point 60-64°C), under the skin of each rat, dorsally in the neck region.

One begins on the day of implantation and administers the compound to be tested - dissolved or suspended in sesame seed oil, corn seed oil, or another physiologically unreactive carrier medium - subcutaneously to each animal in a group at a dose of 10 mg/kg daily for 24 consecutive days. The amount of carrier or mixing medium is so large that a 180 g rat receives approx. 0.1 ml at the beginning of the experiment and - with increasing body weight - approx. 0.2 ml at the end. Each animal in the second group simultaneously receives daily subcutaneous injections of mixing medium which is likewise adapted to body weight and these animals serve as control animals. One day after the treatment, the animals are killed, the seminal vesicles and ventral prostate glands are removed and these are dissected free of extraneous tissue. Fluid is squeezed from the bladders (but not the prostate), after which the glands are dried and weighed. A compound is considered antiandrogenic if the mean weight of the bladders in the treated animal group is significantly less (P at 0.01) than the corresponding weight in the control group animals, and a proportional decrease in the mean prostate weight is found for treated animals vis-a-vis control animals. 17g-Hydroxy-16,16-dimethylestr-4-en-3-one was active in this test.

The anti-sebum effect of 17g-hydroxy-16,16-dimethylestr-4-en-3-one appears from results from standard tests with regard to the ability to reduce the amount of hair grease in rats, carried out essentially as described by F.J. Ebling in Proe. Roy. Soc. Med., 62, 890 (1969). 17Ø-hydroxy-16,16-dimethylestr-4-en-3-one was active subcutaneously in a dosage of 5 mg/kg in this experiment.

The therapeutically active compound 17B-hydroxy-16,16-dimethylestr-4-en-3-one is prepared according to the present invention by acid hydrolysis of a compound with the general formula:

where the alkyl group contains 1-5 carbon atoms and where the dotted line indicates the possible presence of a double bond under the assumption that the second alkyloxy group is optional and is present only when the 2-3 bond is saturated..

Examples of acids that are suitable for the hydrolysis are

strong mineral acids (hydrochloric acid, sulfuric acid.), sulphonic acids and strong organic acids (e.g. trichloroacetic acid). Solvents in which the steroid dissolves, such as tetrahydrofuran, acetone or lower alkanols (such as methanol) are used. The reaction is usually carried out at room temperature and pressure.

The invention will appear more clearly from the following examples.

The quantities of substances are in parts by weight when parts by volume are not specified, and the ratio between parts by weight and parts by volume is like that between grams and milliliters.

Production of starting materials

Example A

A solution of 377 parts of 3-methoxy-16,16-dimethyl-estra-1,3,5(10)-trien-17-one and 30 parts of sodium tetrahydroborate(1-) in 12,000 parts of 2-propanol was heated at boiling point during reflux overnight. The resulting solution was cooled, acidified with a slight excess of acetic acid, concentrated to ca. 1/10 volume by vacuum distillation and then diluted with sufficient water to cause precipitation. After cooling, the precipitate was filtered off, washed with water, dried in air and recrystallized from a mixture of dichloromethane and ethyl acetate. The isolated product is 3-methoxy-16,16-dimethylestra-1,3,5(10)-trien-170-ol which melts at 130-133°C and is further characterized by a specific rotation, at 27°C in 1.09 chloroform solution, at +72.5° (relative to sodium's D line).

Example B

A solution of 314 parts of 3-methoxy-16,16-dimethylestra-1,3,5(10)-trien-17B-ol in 4500 parts of tetrahydrofuran was added to a stirred solution of 4000 parts of tert-butyl alcohol in 105,000 parts redistilled liquid ammonia. Sufficient sodium metal was added portionwise with constant stirring to maintain a deep blue color for 2 hours, whereupon the ammonia was distilled off and the residue steam distilled. A granular solid was filtered from the cooled distillate, washed with water and dried at 60°C in vacuum. The isolated product is 3-methoxy-16,16-dimethylestra-2,5(10)-dien-178-ol which melts in the range 140-147°C.

Example C

A solution of 350 parts of 3,3-dimethoxy-16,16-dimethyl-estr-5(10)-en-17-one in tetrahydrofuran was mixed with 500 parts of lithium aluminum hydride at -10°C for 5 minutes. 900 parts of ethyl acetate were added followed by 50 parts of water, 50 parts by volume of 4M sodium hydroxide and 150 parts of water. The reaction mixture was filtered, the solvent distilled and the residue recrystallized from pentane to 3,3-dimethoxy-16,16-dimethylestr-5(10)-en-170-ol which melts at approx. 99-101°C.

Production of end products

Example 1

About 5 parts 18% hydrochloric acid. About. 1 1/2 hours later, the resulting solution was diluted with 200 parts of water and the mixture was cooled. Insoluble solids were filtered off, washed with water, dried in air and recrystallized from a mixture of methanol and ethyl acetate to give 17g-hydroxy-16,16-dimethylestr-4-en-3-one melting at 172-175° C.

Example 2

The entire quantity of 3,3-dimethoxy-16,16-dimethylestr-5(10)-en-17g-ol prepared in Example C was dissolved in 4000 parts of methanol. 500 parts by volume of 6N hydrochloric acid were added to the solution at room temperature and stirred. After 3 hours the acid was neutralized with sodium hydroxide, the solution was concentrated and diluted portionwise with water. The solid that formed was filtered off, washed with water and dried in air. The solid was recrystallized twice from ethyl acetate to give 170-hydroxy-16,16-dimethylestr-4-en-3-one, mp ca. 167-175°C.

Claims (1)

Analogous process for the preparation of 17g-hydroxy-16,16-dimethylestr-4-en-3-one with therapeutic activity and with the formula: characterized by acid hydrolysis of a compound with the general formula: where the alkyl group contains 1-5 carbon atoms and where the dotted line indicates the possible presence of a double bond under the assumption that the second alkyloxy group is optional and is present only when the 2-3 bond is saturated.