Abstract: The composition of formula I wherein the substituents have various significances, whereby one of R2 to R4 is ethyl. They can be prepared by fermentation, or by replacement of hydroxy with chloro under simultaneous or concomitant epimerization. They are indicated for use as pharmaceuticals in the prevention or treatment of inflammatory conditions and of conditions requiring immunosuppression, optionally in combination or association with further pharmaceutically active and compatible agents, e.g. macrolactam macrolides such as pimecrolimus.