| abstract |
A compound represented by the following formula [I] or an optically active analogue thereof or a salt (in which the bond shown by the dotted line in the five-membered ring means that the five-membered ring can be any cyclopentenic ring having a double bond, and this bond is saturated and, in the case of the cyclopentene ring, X is OH, Y is = O and Z is H, whereas in the case of the cyclopentane ring, X is = O, Y is OH and Z is OH, R is the residue after removal of 2H -g groups of SH-containing compounds). |