DEPOT-STEROID ESTERS

Steroid esters of the Formula I I wherein the A, B, C, and D rings can be substituted in the usual manner, R10 is hydrogen or methyl; R13 is alkyl of 1-3 carbon atoms; R17 is 17 alpha -alkynyl or alkadiinyl of up to 4 carbon atoms or 17 beta -acetyl, Z is X-OH, Y-CO-OH, X-O-CO-Y-CO-OH, X-O-CO-R, Y-CO-OR, X-O-CO-Y-CO-OR, or X-O-SO2-R; X is a straight-chain or branched alkylene of 1-6 carbon atoms, optionally interrupted by O or S atoms, wherein the chain or branches can be substituted by -OH, -O-CO-R, or -O-SO2-R; Y is a direct bond, a straight-chain or branched carbon chain of 1-3 atoms, optionally interrupted by an O or S atom if Y is linked to the steroid residue via -O-CO-; of 1-16 atoms if Y is linked to X via -O-CO; or 1,4-phenylene, 1,4-cyclohexylene, or 1,3-cyclopentylene optionally substituted by alkyl of 1-2 carbon atoms, or groups analogously 1,2- and 1,3-disubstituted, respectively; and R is an optionally substituted alkyl of up to 22 carbon atoms, have longer acting activity than the corresponding unesterified steroids and higher activity than the corresponding long chain esters.