Patent GB-1103988-A (GB)
Title: A process for the preparation of des-a-steroids
IPC: C07C309/73
Filed: 1965-03-29
Abstract: The invention comprises compounds of the formula <FORM:1103988/C2/1> <FORM:1103988/C2/2> <FORM:1103988/C2/3> wherein R10 represents a hydroxy or esterified hydroxy group, R2 represents a hydrogen atom or a lower alkyl group or R10 together with R2 represents an oxo, lower alkylenedioxy or 17b  - hydroxy - 17a  - (lower alkanoic acid) lactone group, R31 represents a hydrogen atom or a lower alkyl, hydroxy or esterified hydroxy group, X represents a hydrogen or halogen atom or a lower-alkyl, lower alkylthio or lower alkanoyl thio group in the 6- or 7-position, compounds of the formula <FORM:1103988/C2/4> wherein R32 represents a hydrogen or fluorine atom or a lower alkyl, hydroxy or esterified hydroxy group, R5 represents a hydrogen or halogen atom, R60 represents a hydrogen or halogen atom or a lower-alkyl, hydroxy or esterified hydroxy group, 20-ketals thereof, 16a ,17b -ketals and acetals of those compounds in which R32 and R60 each represent a hydroxy group, derivatives thereof in which the 20-oxo group is reduced to a 20-hydroxy group and the corresponding derivatives in which said 20-hydroxy group is esterified, compounds having the formula <FORM:1103988/C2/5> wherein R32, X and R60 are as defined above, OA represents a hydroxy or esterified hydroxy group, 17a ,20;20,21-bis-(methylenedioxy) derivatives of those compounds in which OA and R60 each represent a hydroxy group, 17a ,21-ketals and acetals of those compounds in which OA and R60 each represent a hydroxy group, 16a ,17a -ketals and acetals of those compounds in which R32 and R60 each represent a hydroxy group, derivatives thereof in which the 20-keto group is reduced to a 20-hydroxy group and the corresponding derivatives in which the 20-hydroxy group is esterified, compounds of the formula <FORM:1103988/C2/6> wherein R10 and R31 are as defined above, X0 represents X other than halogen, EO represents hydroxy or esterified hydroxy and R21 represents a hydrogen atom or a lower alkyl, lower alkenyl or lower alkynyl group, compounds having the formula <FORM:1103988/C2/7> wherein R32, R5, R60, X0 and EO are as defined above, 20-ketals thereof, 16a ,17a -ketals and acetals of those compounds in which R32 and R60 each represent a hydroxy group, derivatives thereof in which the 20-oxo group is reduced to a 20-hydroxy group and the corresponding derivatives in which said 20-hydroxy group is esterified, compounds of the formula <FORM:1103988/C2/8> wherein R32, R60, OA, X0, and EO are as defined above, 17a ,20;20,21-bis(methylene dioxy) derivatives of those compounds in which OA and R60 each represent a hydroxy group, 17a ,21-ketals thereof and acetals of those compounds in which R60 and OA each represent a hydroxy group, 16a ,17a -ketals and acetals of those compounds in which R32 and R60 each represent a hydroxy group, derivatives of those compounds in which the 20-keto group is reduced to a 20-hydroxy group and the corresponding derivatives in which said 20-hydroxy group is esterified, and a process for the preparation of 9b ,10b -des-A-androstan (or pregnan)-5-ones, which process comprises catalytically hydrogenating a des-A-androst (or pregn)-9-en-5-one.