DE1170948B - Process for the preparation of 6ª ‡, 16ª ‡ -dimethyl-11ª ‰, 17ª ‡, 21-trihydroxy-4-pregnen-3, 20-dione or. its 21-acetate - Google Patents

Description

Process for the preparation of 6a, 16a-dimethyl-I 1f, 17a, 21-trihydroxy-4-pregnen-3,20-dione or its 21-acetate. The invention relates to a process for the production of 6a, 16a-dimethyl-11ß, 17a, 21-trihydroxy-4-pregnen-3,20-dione or its 21-acetate.

These 6a, 16a-dimethyl steroids are powerful anti-inflammatory and special effective in treating arthritis and related diseases as they are used to Exercise of their cortisone-like effect administered only in very low doses need to be, thereby largely eliminating unwanted side effects will.

The starting material used is a 16a-methyl-3ß, 17a, 21-trihydroxy - 5 - pregnen - 20 - an - 3 - tosylate-21-acylate, which according to the process of the invention with methyl ethyl ketone and a weak base, e.g. B. potassium acetate, in a known manner to the corresponding 16a-methyl-3,5-cyclo-6ß, 17a, 21-trihydroxy - pregnane - 20 - an - 21- acylate of the all- common formula CH20R C = O OH _____CH3 OH in which R is an acyl radical, is implemented. The 16a-methyl-3,5-cyclo-6ß, 17a, 21-trihydroxy-pregnan-20-one-21-acylate obtained is treated with an oxidizing agent such as chromium trioxide in a manner known per se to form the corresponding 16a - methyl - 3,5-cyclo-17a, 21-dihydroxy-pregnane-6,20-dione-21-acylate of the general formula implemented, in which R has the above meaning. The 16a-methyl-3,5-cyclo-17a, 21-dihydroxy-pregnane-6,20-dione-21-acylate obtained becomes the 21-alcohol, namely 16a-methyl-3,5-cyclo, in a manner known per se -17a, 21-dihydroxy-pregnane-6,20-dione, hydrolyzed, which is represented by the formula is pictured.

The 16a-methyl-3,5-cyclo-17a, 21-dihydroxy-pregnane-6,20-dione obtained is converted into 16a-methyl-3,5-cyclo-17a with formaldehyde in the presence of a strong acid in a manner known per se , 20; 20,21-bis-methylenedioxy-pregnan-6-one of the formula implemented. The in itself. Treatment of the 16a-methyl-3,5-cyclo-17a, 20; 20,21-bis-methylenedioxy-pregnan-6-one obtained in a known manner with methyl magnesium gives a mixture of the isomers of 6e, 16a-dimethyl-3,5 -cyclo-6e-hydroxy-17a, 20; 20,21-bis-methylenedioxy-pregnane of the formula which is rearranged to remove the OH group in the 6-position in a manner known per se by acid treatment, a 6,16a-dimethyl-3ß-hydroxy-17a, 20; 20,21 - bis -methylenedioxy-5-pregnen- 3ß-acylate of the general formula arises, in which R has the above meaning.

The 6,16a-dimethyl-3ß-hydroxy-17a, 20; 20,21-bis-methylenedioxy-5-pregnen-3ß-acylate is pregnen in a manner known per se to 6,16a-dimethyl-3ß-hydroxy-17a, 20; 20,21-bis-methylenedioxy-5-pregnen of the formula hydrolyzed. The 6,16a-dimethyl-3ß-hydroxy-17a, 20; 20,21-bis-methylenedioxy-5-pregnen is converted with cyclohexanone and aluminum isopropoxide in a manner known per se to 6a, 16a-dimethyl-17a, 20; 20,21-bismethylenedioxy-4-pregnen-3-one of the formula implemented. By the known action of an aqueous organic acid on 6a, 16a - dimethyl - 17a, 20; 20,21-bis-methylenedioxy-4-pregnen-3-one forms 6a, 16a - dimethyl - 17a, 21 - dihxdroxy - 4 - pregnen-3,20-dione of the formula The 6a, 16a-dimethyl-17a, 21-dihydroxy-4-pregnen-3,20-dione obtained is microbiologically produced with the aid of a strain of Curvularia lunata in a manner known per se to form 6a, 16a-dimethyl-11β, 17a , 21-trihydroxy-4-pregnen-3,20-dione is oxidized. This compound is powerful anti-inflammatory and particularly effective in treating arthritis and related diseases. Curvularia lunata can e.g. By the Northern Regional Research Laboratory (No. 2434), Peoria, 111., or from natural sources, e.g. B. earth, be isolated in a known manner.

The 6a, 16a-dimethyl-11ß, 17a, 21-trihydroxy-4-pregnen-3,20-dione obtained can by treatment with acetic anhydride in a manner known per se in transfer the 21-acetate, which by recrystallization from benzene petroleum ether is cleaned; this gives practically pure 6a, 16a-dimethyl-I 1β, 17a, 21-trihydroxy-4-pregnen-3,20-dione-21-acetate.

In the general formulas given above, R denotes a Acyl radical, e.g. B. the benzoyi, acetyl or propionyl radical. Example a) 16a-Methyl-3,5-cyclo-6ß, 17a, 21-trihydroxypregnan-20-one-21-acetate A mixture of 16.6 mg of 16a-methyl-3ß, 17a, 21-trihydroxy-5-pregnen-20-one-3-tosylate-21-acetate, 1 ml of methyl ethyl ketone, 21 mg of potassium acetate and 0.2 ml of water is refluxed for 18 hours heated. The methyl ethyl ketone is evaporated in a stream of nitrogen and the residue triturated with water, then dissolved in benzene-ethyl acetate. The organic layer is washed with saturated sodium bicarbonate solution and water, dried and evaporated to dryness. An oil is obtained. A max @ '= 2.75 to 2.90 #L, 5.74 #t (sh) and 5.78 V .. The residual oil is made to crystallize from acetone, to pure acetone solvate of 16a-methyl-3,5-cyclo-6ß, 17a, 21-trihydroxy-pregnan-20-one-21-acetate to deliver.

= 2.85 to 2.97 #t, 5.74 v. (sh), 5.81 and 5.91 V. Analysis for C2414360.5 - C3Hs0: Calculated ... C = 70.01, H = 9.15; found ... C = 69.80, H = 8.84. b) 16a-methyl-3,5-cyclo-17a, 21-dihydroxypregnane-6,20-dione-21-acetate in a solution of 50 mg 16a-methyl-3,5-cyclo-6ß, 17a, 21-trihydroxy = pregnan-20-one-21-acetate in 0.5 ml of pyridine, a solution of 50 mg of chromium trioxide in 0.5 ml of pyridine is added and the mixture is left to stand at 20 ° C. for about 15 hours. The reaction mixture is diluted with hot benzene and filtered through diatomaceous earth. The benzene filtrate is washed successively with 1N hydrochloric acid, water, sodium bicarbonate solution and water, dried, filtered and concentrated to dryness. On crystallization from ethyl acetate, the residue gives petroleum ether 16a-methyl-3,5-cyclo-17a, 21-dihydroxy-pregnane-6,20-dione-21-acetate. .i ccHcb = 5.74 #t (sh), 5.79 [. and 5.95 u .. c) 16a-methyl-3,5-cyclo-17a, 21-dihydroxy-pregnane-6,20-dione In a solution of 363 mg 16a-methyl-3,5-cyclo-17a, 21- dihydroxy-pregnane-6.20-dione-21-acetate in 20 ml of purified methanol is added 0.42 ml of 2.16 N sodium methylate solution in methanol. The solution is stirred for 8 minutes, then made weakly acidic with acetic acid and diluted with water. The precipitate is filtered off. The hydrolyzed product, 16a - methyl - 3,5 - cyclo-17a, 21-dihydroxy-pregnane-6,20-dione, is washed thoroughly with water and made available as such for the next stage of the process. d) 16a-methyl-3,5-cyclo-17a, 20; 20,21-bismethylenedioxy-pregnan-6-one In a mixture of 0.280 g of 16a-methyl-3,5-cyclo-17a, 21-dihydroxy-pregnan -6,20-dione in 11 ml of chloroform, a solution, premixed at 0 ° C., of 2.8 ml of concentrated hydrochloric acid and 37% formaldehyde, which contains little methanol, is added. The two-phase system is stirred for 24 hours at 20 ° C. under nitrogen. The chloroform layer is separated and the aqueous layer is extracted twice with 25 ml of chloroform each time. The combined chloroform extracts are washed with saturated sodium bicarbonate solution and water, dried and concentrated to dryness. The residue is rinsed twice with 20 ml of methanol each time, then dissolved in benzene and chromatographed on magnesium silicate, known under the trade name Florosil. The column is eluted successively with 1, 3, 5 and 7.5% acetone in n-hexane. The crystal fractions from the 50% acetone, which give a negative tetrazolium blue test, are combined and converted from methanol to form practically pure 16a-methyl-3,5-cyclo-17a, 20; 20,21-bis-methylenedioxy-pregnan-6-one recrystallized. e) Isomer mixture of 6e, 16a-dimethyl-3,5-cyclo-6e-hydroxy-17a, 20; 20,21-bis-methylenedioxy-pregnane In a solution of 150 mg of 16a-methyl-3,5-cyclo-17a , 20; 20,21-bis-methylenäioxy-pregnan-6-one in 25 ml of ether, 1 ml of 3 molar methyl magnesium solution in ether is added dropwise. The mixture is refluxed for 2 hours, cooled and excess Grignard reagent is decomposed with saturated ammonium chloride solution. The ether layer is separated off and the aqueous layer is extracted with chloroform. The combined organic extracts are washed with water, dried and concentrated. The residue, which probably represents an isomer mixture of 6e, 16a-dimethyl-3,5-cyclo-6e-hydroxy-17a, 20; 20,21-bis-methylenedioxy-pregnane, is provided for the next step without purification.

f) 6,16a-dimethyl-3ß-hydroxy-17a, 20; 20,21-bismethylenedioxy-5-pregnen-3ß-acetate A solution of 150 mg of the isomer mixture of 6e, 16a-dimethyl-3,5-cyclo-6e-hydroxy-17a, 20; 20,21-bis-methylenedioxy-pregnen in 2 ml of 10% sulfuric acid in acetic acid Stirred for about 15 hours at 20 ° C. and the mixture is diluted with ice water. The solid is filtered off, washed thoroughly with water and dried. 6.16a is obtained - Dimethyl - 3ß - hydroxy - 17a, 20; 20,21 - bismethylenedioxy-5-pregnen-3ß-acetate. g) 6,16a-Dimethyl-3ß-hydroxy-17a, 20; 20,21-bismethylenedioxy-5-pregnen The above 6,16a-dimethyl-3ß-hydroxy-17a, 20; 20,21-bis-methylenedioxy-5-pregnene obtained. 3ß-acetate is made by dissolving in 0.5 ml of methanol. Added 50 mg of potassium carbonate and refluxing on the steam bath for one hour. The mixture is cooled, diluted with 1 ml of water and methanol in a stream of nitrogen freed by evaporation. Of the filtered precipitate is thorough Washed with water and from aqueous methanol to 6,16a-dimethyl - 3ß - hydroxy - 17a, 20; 20,21 - bis - methylenedioxy-S-pregnen recrystallized.

h) 6a, 16a-dimethyl-17a, 20; 20,21-bis-methylenedioxy-4-pregnen-3-one A solution of 5 ml of toluene and 100 mg of 6,16a-dimethyl-3β-hydroxy-17a, 20; 20.21 - bis - methylenedioxy-5-pregnen are mixed with 0.25 ml of cyclohexanone and 125 mg of redistilled aluminum isopropoxide. The mixture is heated on the reflux condenser for 45 minutes, 0.25 ml of a solution of potassium tritartrate is added and the toluene and cyclohexanone are removed by steam distillation. The cooled aqueous suspension is extracted with chloroform. When the chloroform is concentrated in vacuo, an oil is obtained which is triturated with petroleum ether to remove the traces of cyclohexane. The residue is thoroughly dried in vacuo and upon crystallization from benzene-heptane 6a, 16a-dimethyl-17a, 20; 20,21-bis-methylenedioxy-4-pregnen-3-one.

i) 6a, 16a-dimethyl-17a, 21-dioxy-4-pregnen-3,20-dione A solution of 70 mg 6a, 16a-dimethyl-17a, 20; 20,21-bis-methylenedioxy-4-pregnen-3-one in 7 ml of 50% acetic acid is heated on the steam bath under nitrogen for 8 hours. The solution is concentrated to dryness in vacuo. The residue is dissolved in chloroform and washed with saturated sodium bicarbonate solution. The filtered chloroform solution is concentrated to a small volume and then spread out on paper strips. The paper is immersed in a formamide-methanol solution (1: 2) and air-dried at room temperature for 15 minutes. The strips are developed with benzene as the mobile phase and air dried. The paper chromatogram is exposed to UV light, with several spots in the chromatogram fluorescing. The largest of these spots which react positively to tetrazolium blue is eluted with ethyl acetate. The ethyl acetate solution is washed with water, dried and concentrated to a small volume. Petroleum ether precipitates 6a, 16a-dimethyl-17a, 21-dihydroxy-4-pregnen-3,20-dione. k) 6a, 16a-Dimethyl-llß, 17a, 21-trihydroxy-4-pregnen-3,20-dione A medium of the following composition is produced Glucose .................. ...... 20 g Digested enzymatic lactalbumin ("Edamin") ....... 20 g corn mash liquor. . . . . . . . . . . . 5 ml made up with water. . . . . . . . . 1 1 This medium is poured into suitable vessels in proportions of 50 ml. The pH is adjusted to 6.5 using 1 molar potassium hydroxide solution and sterilized at 120 ° C. for 12 minutes.

The partial media in the individual vessels are now with an aqueous Suspension of spores of the strain Curvularia lunata (Northern Regional Research Laboratory No.2434) and inoculated at 28 ° C in a rotating shaker 48 Hours incubated.

10 mg each of the 6a, 16a-dimethyl-17a, 21-dihydroxy-4-pregnen-3,20-dione obtained in the previous step are introduced into each vessel in the form of a dimethylformamide solution (100 mg (ml). The incubation is carried out during The whole broth is then extracted three times with equal volumes of ethyl acetate; the extracts are combined and finally concentrated. 3,20-dione is filtered off, mp = 239-242 ° C; maz @ H = 242 m [.; e = 15 300. analysis for C2311,3,05.:. ... Calculated C = 70.74, H = 8.78; found ... C = 70.83, H = 8.66 The obtained 6a, 16a-dimethyl-11, 17a, 21-trihydroxy-4-pregnen-3,20-dione is obtained by Treatment with acetic anhydride and pyridine is converted into the 21-acetyl derivative, which is purified by recrystallization from benzene petroleum ether. Practically pure 6a, 16a-dimethyl-llß, 17a, 21-trihydroxy-4-pregnen-3,20-dione is obtained. 21-acetate, mp = 193 up to 197 ° C; dm "; @H = 241 m @, L; F = 14,900. Analysis for C.2sHss0s: Calculated ... C = 69.41, H = 8.39; found ... C = 69.42, H = 8.39.

Claims (3)

Claims: 1. Process for the production of 6a, 16a-dimethyl-11 ß, 17a, 21-trihydroxy-4-pregnen-3,20-dione or its 21-acetate, thereby g e n n -z e i c h n e t that a 16α-methyl-3β, 17a, 21-trihydroxy-5-pregnen-20-one-3-tosylate-21-acylate can be obtained in a manner known per se reacted with a weak base in methyl ethyl ketone, the 16a - methyl obtained - 3,5 - cyclo - 6ß, 17a, 21 - trihydroxypregnan-20-one-21-acylat oxidized in the 6-position, the 16a-methyl-3,5-cyclo-17a, 21-dihydroxy-pregnane-6,20-dione-2l = acylate obtained hydrolyzed, the 21-hydroxy compound obtained with formaldehyde in the presence of a strong acid, the 16a-methyl-3,5-cyclo-17a, 20; 20,21-bis-methylenedioxy-pregnan-6-one reacted with methyl magnesium, the resulting mixture of isomers of 6e, lba-dimethyl-3,5-cyclo-6e-hydroxy-17a, 20; 20,21-bis-methylenedioxy-pregnane rearranged by acid treatment, in the obtained 6,16a-dimethyl-3ß-hydroxy - 17a, 20; 20,21-bis-methylenedioxy-5-pregnen-3-acylate is the 3ß-acylate group hydrolyzed and the 3ß-hydroxy group formed with aluminum isopropylate and cyclohexanone oxidizes the compound so formed with an aqueous organic Acid into the corresponding 6a, 16a-dimethyl -17a, 21- dihydroxy- 4- pregnen - 3.20- dion transferred, the latter microbiologically with the help of a strain of Curvularia lunata oxidized and the 6a, 16a-dimethyl-11ß, 17a, 21-trihydroxy-4-pregnen-3,20-dione obtained optionally acetylated in the 21-position using acetic anhydride. 2. The method according to claim 1, characterized in that there is used for the oxidation of 16a - methyl - 3,5 - cyclo - 6ß, 17a, 21 - trihydroxypregnan -20-one-21-acylate chromium trioxide in the presence of pyridine. 3. The method according to claim 1, characterized in that the hydrolysis of the 21-position ester group is carried out using sodium methylate. Documents considered: German Auslegeschrift No. 1030 830; Journ. Chem. Soc., 1957, p. 665 and 1938, p. 759; Journ. At the. Chem. Soc., Vol. 77 (1955), p. 763, and Vol. 80 (1958), p. 1517.