METHOD OF ISOMERIZATION OF EQUILIN Russian patent published in 2001 - IPC

FIELD: chemical industry. SUBSTANCE: described is method of isomerization of equilin or derivative thereof into delta (8,9)-dehydro estrone delta(8,9)DHE, is H, alkyl, acyl or silyl (alkil)₃, R₂ is H₁ and R₃ is OH, O-alkyl or O-silyl (alkil)₃ or R₂ and R₃ together are 0, or R₂ and R₃ together are acetal or cycloacetal group. Equilin or derivative thereof is reacted with lithium salt of ethylene diamine or lithium amide in dimethyl sulfoxide. Method makes it possible to prepare pure delta (8,9)DHE under no acid conditions. Yield of dalta (8,9) is 95%. EFFECT: more efficient isomerization method. 6 cl, 8 ex