To obtain the subject new compound which is selective estrogen receptor modulator and useful for treating estrogen-related disorder such as postmenopausal syndrome, osteoporosis or hyperlipemia.

This compound is represented by formula I (R is H, a 1-4C straight-chain or branched chain alkyl; dotted line represents an arbitrary double bond and when the arbitrary double bond exists, H in parentheses does not exist), e.g. 3-α-hydroxy-8-methoxy-3aα-methyl-2,3,3a4,5,10bα-hyxahydro-1H- benzo[b]indeno[5,4-d]thiophen, etc. Furthermore, the compound of formula I includes its stereoisomer. The compound of formula II in the compound of formula I is obtained by reacting a solution of 3αβ-methyl-8-methoxy-1H- benzo[b]indeno[5,4-d]thiophen-3-one with sodium hydrogen boride.