摘要
11β-Hydroxy-androst-4-en-3,17-dione(1a),androst-4,9(11)-dien-3,17- dione-(2a),androst-4-en-3,11,17-trione(3a),11α-methoxy-androst-4-en-3,17-dione (4a)and 11β-metboxy-androst-4-en-3,17-dione(Sa)were selectively reduced to the corresponding 17β-OH derivatives in one step without the protection of 3- oxo(and 11-oxo,in the case of 3a)group with the yields ranging from 65% to 79%.In these reactions,the ditute NaBH_4(or KBH_4)solution in methanol was added dropwise to the 3,17-dioxo-steroids solution in methanol-benzene-pyridine, while the reaction mixtures were well stirred at -5～5℃.Acid(such as gtacial acetic acid)was added to quench the reactions.The resulted testosterone derivatives(1b～5b)were purified by flash chromatography. This method appties to the reduction of other 3,17-dioxo-steroids such as△~1 -3-one,△^(1.4)-3-one,△^(4.6)-3-one,△^(1.4.6)-3-one containing compounds.
11β-Hydroxy-androst-4-en-3,17-dione(1a),androst-4,9(11)-dien-3,17- dione-(2a),androst-4-en-3,11,17-trione(3a),11α-methoxy-androst-4-en-3,17-dione (4a)and 11β-metboxy-androst-4-en-3,17-dione(Sa)were selectively reduced to the corresponding 17β-OH derivatives in one step without the protection of 3- oxo(and 11-oxo,in the case of 3a)group with the yields ranging from 65% to 79%.In these reactions,the ditute NaBH_4(or KBH_4)solution in methanol was added dropwise to the 3,17-dioxo-steroids solution in methanol-benzene-pyridine, while the reaction mixtures were well stirred at -5～5℃.Acid(such as gtacial acetic acid)was added to quench the reactions.The resulted testosterone derivatives(1b～5b)were purified by flash chromatography. This method appties to the reduction of other 3,17-dioxo-steroids such as△~1 -3-one,△^(1.4)-3-one,△^(4.6)-3-one,△^(1.4.6)-3-one containing compounds.
