Cylosporins e.g. of formula II ##STR1## in which X is -MeBmt- or -dihydro-MeBmt- andY is -.alpha.Abu-, -Thr-, -Val- or -Nva-,wherein the residue at the 3-position, i.e. the residue Z in formula II, is an optically active, .alpha.-N-methylated .alpha.-amino acid residue of the (D)-configuration, possess pharmaceutical, in particular immunosuppressive, anti-inflammatory and anti-parasitic activity, Intermediate cyclosporin poly-anions having a de-protonated sarcosyl residue at the 3-position, e.g. polyanions of cyclosporins of formula II above wherein X and Y have the meanings given above and Z is -Sar-, in which the said residue Z is de-protonated, are also novel and part of the invention.