Abstract: There are provided compounds of formula (I), wherein R.sup.1 represents H, OH or alkoxy; R.sup.2 represents H; in addition R.sup.1 and R.sup.2 may together represent a second bond between the carbon atoms to which they are attached; R.sup.3 represents methyl, ethyl, propyl or allyl; R.sup.4 represents H, OH, alkyl, alkoxy, halogen, amino, S-alkyl, NHCHO or NHCO-alkyl; n represents 1 or 2; X represents O, (H, OH), (H, H) or .dbd.NH; and Y represents an optionally substituted cyclohexyl or substituted cyclopentyl group; with various provisos. The compounds are useful, inter alia, as immunosuppressive agents.