Definition: Androstanes in which ring contractions have occurred or which are lacking carbon-18. Compounds with any degree of unsaturation are included. Androstanes which are lacking carbon-19 are ESTRANES.
Chinese Med J 2(3):177;1976; Contraception 1979;20(6):549; Int J Gynaecol Obstet 1978-1979;16(6):573; Scientia Sinica 18(2):262;1975; Steroids 33(1):85;1979; Yao Hsueh Hsueh Pao 1979;14(8):502