| 摘要 |
PURPOSE:To selectively obtain an E type prostaglandin containing a cis double bond in an alpha chain useful for treating peripheral circulatory disorders, etc., by reducing an E type prostaglandin having a triple bond in an alpha chain with formic acid in the presence of a specific catalyst. CONSTITUTION:An E type prostaglandin having a triple bond of formula I (R is H, 1-4C alkyl, etc.; R<4> and R<5> are H or hydroxyl group-protecting group; A, R<6> and R<7> are arbitrary group not participating in reaction; B is C-C single bond or A; Y is ethynylene) or its ester is reacted with formic acid in the presence of a zero-valent vibalent Pd complex or complex salt [e.g. tris(dibenzylideneacetone)dipalladium (0) chloroform] to give the objective compound of formula II (R' is H when R is H, etc., and is 1-4C alkyl when R is 1-4C alkyl). Except a case where the Pd complex or the complex salt is mixed with a phosphine, a phosphine such as triethylphosphine is prederably added to the reaction system. |
