Patent GB-1072094-A (GB)
Title: Steroid triazoles
IPC: C07D249/16
Filed: 1964-06-11
Abstract: Novel steroids of the formula <FORM:1072094/C2/1> (wherein the 6(7)-dotted line indicates that this bond is saturated or unsaturated; R1 is hydrogen, b -chlorine, b -hydroxy or keto but is b -chlorine only when X is halogen and is hydrogen only when X is hydrogen; R2 is hydrogen, a -chlorine, a -fluorine or a -methyl; R3 is hydrogen, a -fluorine, a -methyl, a -hydroxy, b -methyl or methylene; R4 is hydrogen, chlorine, fluorine, hydroxy, acyloxy or a dihydrogen phosphate group or alkali metal salt thereof; R5 is hydrogen, alkyl, aralkyl, cycloalkyl, aryl or heterocyclic; X is hydrogen or halogen), the 16-acetals and -ketals of those compounds in which R3 is a -OH derived from carbonyl compounds of the formula P.CO.Q (wherein each of P and Q is hydrogen, alkyl or aryl or, together with the carbon atom to which they are attached, cycloalkyl), the corresponding compounds in which R5 is on the 11- or the 31-nitrogen atom, and the acid-addition salts of these compounds; are prepared (1) when R5 is other than H and is on the 21-nitrogen, by converting the appropriate 17a ,21-dihydroxy-4-pregnene- (or 4,6-pregnadiene)3,20-dione to the 17a ,20:20,21-bismethylenedioxy derivative, reacting this with an alkyl formate and sodium hydride in an inert atmosphere to form the 2-hydroxymethylene compound, converting this with nitrous acid to the 2-hydroxyimino compound, reacting this with a mono-substituted hydrazine to give the corresponding 3-hydrazone, dehydrating this to form the triazine ring, and removing the bis-ketal protecting group with formic acid; (2) when R5, when present, is on the 21-nitrogen, by refluxing the 2-hydroxyimino-3-keto compound formed in (1) with hydrazine or a mono-substituted hydrazine to form the triazine ring directly, and removing the protecting group as in (1); (3) when R5, when present, is on the 11- or 31-nitrogen atom, by converting the appropriate 17a ,21-dihydroxy-4-pregnene-3,11,20-trione to the 17a ,20:20,21-bismethylenedioxy derivative, converting this to the corresponding D 5-3-ethyleneketal, converting this with a per-organic acid to the 5a ,6a -epoxide, treating this with formic acid to give the 3,6,11-trioxo-5a -pregnane compound, refluxing with morpholine to produce the corresponding D 2-3-morpholino -6,11-dioxo-compound, refluxing with an azide to form the triazine ring, reducing the 6-keto group to the 6b -ol, dehydrating to the corresponding D 5 compound, isomerizing this to the D 4 compound, reducing to the 11b -ol and removing the side chain protecting group; (4) when R5 is as in (3) and a D 6-6-methyl group is also required, reacting the 6-keto-triazine formed as in (3) with methyl magnesium iodide to give the 6b -hydroxy-6a -methyl compound, dehydrating to the D 5-compound, refluxing with selenium dioxide to give the 4-hydroxy derivative, reducing the 11-keto group, removing the side chain protecting group and heating with an alkali metal alkoxide.  Mixtures of 11, 21 and/or 31 isomers prepared as above or by alkylation of N-unsubstituted compounds may be separated by chromatography.  The following methods of preparation are also described (a) the D 5-compound prepared as in (3) is converted to the 5a ,6a -epoxide, this with a methyl Grignard reagent gives the 6b -methyl-5a -hydroxy compound, this is dehydrated to the D 4-6b -methyl compound and this is epimerized to the 6a -methyl compound; or the 5a ,6a -epoxide with hydrohalic acid gives the 6b -halo-5a -hydroxy compounds which are dehydrated to the D 4-6b -halo-compounds which with chloranil give the D 4,6-6-halo-compounds; or the D 5-compound with HF gives the 5a ,6a -difluoro compound and this is treated with a strong base and neutralized to give the D 4-6a -fluoro compound or reacted with phenyliodosochloride to give the 5a ,6a -dichloro compound which similarly gives the D 4-6a -chloro compound; (b) the 6b -ol prepared as in (3) is converted to the 6b -acetoxy compound, the 11-keto group is reduced, the 11b -ol is dehydrated to the D 9(11)-compound, this is converted to the 9a -bromo-11b -ol, this to the 9b ,11b -epoxide, this to the 9a -fluoro-11b -ol, this to the 11-one, the 6b -acetoxy group is hydrolysed, the 6b -ol dehydrated and the D 5-product used in any of the appropriate processes detailed above; (c) the 9b ,11b -epoxy-6b -acetoxy compound of (b) is hydrolysed, the 6b -ol is oxidized and the 6-one is treated by methods described above to give finally the D 4,6-6-methyl-9a -fluoro-11b -hydroxy compound; (d) the D 9(11)-compound of (b) is converted to the 9a ,11b -dichloro compound and the product converted to compounds of the invention by methods described above; (e) the D 5-3-ketal of (3) is heated with hydrazine to give the corresponding 11-unsubstituted compound, and this is subjected to the further processes of (3); (f) acylations and hydrolyses are described, e.g. removal of N- and/or 21-acyl groups with sodium methoxide in methanol; N,21-diacylation and subsequent hydrolysis with aqueous acetic acid to remove the N-acyl group selectively; (g) 21-ols are converted to 21-unsubstituted products via 21 mesylates (with previous N-carbamoylation) and 21-iodo compounds; or to 21-fluoro products, the 21-mesylates and alkali fluorides giving a mixture of the required 21-fluorides and 17a ,21-epoxy compounds which are separated by chromatography; or to 21-chloro products; (h) 16-ols are prepared by microbiological hydroxylation, e.g. with Streptomyces roseochromogenous, of 16-unsubstituted compounds; (i) 16a ,17a -acetals and ketals are prepared from the diols and aldehydes or ketones; (j) 21-phosphates are prepared from the 21-iodo compounds, and are converted to alkali metal salts; (k) 11-ols are oxidized to 11-ones; and (l) acid-addition salts are prepared. Many of these processes can be applied to the preparation of starting materials not containing the triazine ring.  6a  - Fluoro - 11b ,21 - dihydroxy - 4,17(20)-pregnadien - 3 - one 21 - acetate is prepared by reacting the 3-anol ethyl ether of methyl 3,11-diketo-4,17(20)-pregnadien-21-oate with perchloryl fluoride to give methyl 6(a  and b )-fluoro-3,11 - diketo - 4,17(20) - pregnadien - 21 - oate, and hydrolysing, reducing and acetylating this. The corresponding 6a -chloro compounds are prepared by similar methods, using N-chlorosuccinimide. These products and the corresponding 6-unsubstituted compound are heated with selenium dioxide to give the corresponding 16a -ols, these are reacted with thionyl chloride to give 20-chloro-21-acetoxy-11b -hydroxy-4,16-pregnadien-3-one or the corresponding 6a -halo compound, these are converted to the corresponding 20,21-epoxy compounds, these with HF and subsequent acetylation give 21-acetoxy-16a -fluoro - 11b  - hydroxy - 4,17(20 - pregnadien - 3 - one and the corresponding 6a -halo compounds, these are oxidized to the corresponding 17a -hydroxy - 21 - acetoxy - 20 - keto compounds, these before or after side-chain protection, are converted by chloranil to 17a ,20:20,21-bismethylenedioxy - 16a  - fluoro - 11b  - hydroxy-4,6-pregnadiene-3,20-dione and the corresponding 6a -halo compounds.  The corresponding 6a -methyl compounds are prepared similarly.  The 6a -halo compounds may also be prepared by converting 11-keto-progesterone to 6-dehydro-11-keto-progesterone oxidizing this to 6a ,7a -oxido-11-keto-progesterone, converting this to the 6-halo-6-dehydro-11-keto-progesterones and converting these to methyl 6-halo-3,11-diketo-4,6,17(20)-pregnatrien-21-oates which are then processed as above.  The preparation of phenyl azide from phenyl hydrazine hydrochloride is also described.  The [3,2-d]-triazolo-steroids of the invention, which are stated to possess anti-inflammatory activity, may be made up into solid or liquid pharmaceutical compositions with suitable carriers.