PURPOSE: To readily and efficiently obtain 7-substituted prostaglandins by subjecting aldehydes which are new intermediates to addition reaction with acetylenes and binding an α-chain having a cycloalkylene group thereto.
CONSTITUTION: Acetylenes expressed by formula II {R5 is H, stannyl or organosilyl; R6 is H, 1-10C alkyl, aralkyl, aryl, stannyl, organosilyl or cation; (k), (l), (m) and (n) are 0-6; 0≤[(k)+(n)]≤4; 0≤[(l)+(m)]≤6} are added to new aldehydes expressed by formula I [R1 to R3 are H or protecting group; R4 is (substituted)1-10C alkyl, alkenyl or (substituted)5- to 6-membered ring cycloalkyll to afford the objective 7-substituted prostaglandins expressed by formula III [R7 is H, stannyl or organosilyl; R8 is H, 1-10C alkyl, aralkyl, aryl, stannyl or organosilyl]. The compounds expressed by formula I are readily obtained by passing, e.g. a compound expressed by formula IV through a compound expressed by formula V.
SHIMADA TOYOMICHI
YASUDA ARATA
