Improvements in Acylated Steroids

1,159,490. Steroid 17-esters. BOOTS PURE DRUG CO. Ltd. 18 Jan., 1967 [9 Feb., 1966; 15 Dec., 1966], Nos. 30018/68 and 30019/68. Divided out of 1,158,492. Heading C2U. Compounds of the Formula (I) (wherein A represents >CH 2 , >C = CH 2 , >CH(R‹-#), or >CH(R‹-α) where R‹ is acyloxy, fluorine, chlorine or methyl; R1 is hydrogen, fluorine or methyl optionally substituted by one or more fluorine atoms; R2 is alkyl; and R3 is hydrogen, fluorine or chlorine) are prepared (a) by reduction of the corresponding 11-keto compounds (which are novel when A is >CH 2 , except for the #1'4 compounds where R3 is hydrogen while R1 is methyl or fluorine) using NaBH 4 , KBH 4 , or LiAl(OR4) 3 H where R4 is alkyl, (b) by dehydrogenation of the corresponding 1,2-saturated compound using 2,3 - dichloro - 5,6 - dicyano - benzoquinone or, provided that R‹ is not acyloxy when A is one of the CHR‹ groups above, using enzymes from cultures, e.g. of Corynebacterium simplex. Bacillus sphaericus or Septomyxa affinis, and (c) by reduction of the corresponding 9α - bromo or chloro - 11#- hydroxy compound (provided that R‹ (where A is CHR‹) and R3 are not chlorine, using chromous acetate in the presence of an alkanethiol. The aforementioned 11-keto compounds are prepared by acylation of the corresponding 17α-hydroxy compounds, or by dehydrogenation of the corresponding 1,2-saturated compounds which themselves are obtained from corresponding 17α-hydroxy compounds. 21-Desoxyprednisone is obtained (using chromic acid and manganous ions) from 21-desoxyprednisolone or its 11α-OH epimer, the latter two compounds being obtained from 1,2- dehydro - 17α - hydroxy - progesterone; all these compounds are obtainable by dehydrogenation of their respective analogues containing only a #4-double bond. 21-Desoxycortisone is obtained (using chromic acid and manganous ions) from 21-desoxyhydrocortisone which in turn is obtained from progesterone, either directly using Cephalothecium roseum, or via 11α or #-hydroxyprogesterone or 17α - hydroxyprogesterone. 11- Hydroxylation may be effected using Rhizopas nigricans, Cunninyhamella blakeslieana, Aspergillus ochraceus, Absidea spp., or Curvularia spp. 9α - Bromo - 21 - desoxyprednisolone 17α- propionate is obtained from 1,9(11)-bisdehydro - 17α - hydroxyprogesterone via either 1,9(11) - bisdehydro - 17α - propionyloxy - progesterone or 21 - desoxy - 9α - bromoprednisolone- 17α-propionate.