Abstract: The invention relates to new ergol-8-ene and ergoline derivatives of the general formula /I/ ##STR1## wherein x y stands for --CH.dbd.C.dbd. or --CH.sub.2 --CH.dbd. group,R stands for hydrogen atom or methyl group,R.sub.1 stands for hydrogen or halogen atom,R.sub.2 stands for lower alkylsulfonyloxy group, phenylsulfonyloxy group optionally substituted with a lower alkyl group, or azido group,R.sub.3 stands for lower alkylsulfonyloxy group or phenylsulfonyloxy group optionally substituted with a lower alkyl group, and acid addition salts thereof. These compounds can be prepared from compounds of the general formula II ##STR2## wherein x y and R are as defined above, by reacting at least two equivalents of a lower alkylsulfonic acid chloride or phenylsulfonic acid chloride substituted with lower alkyl group.

Abstract: The invention relates to novel enkephalin analoge of the general formula IH.sub.2 N-C(NH)-Tyr-A-Gly-Phe-B (I)whereinTyr, Gly and Phe stand for an L-tyrosine, glycine and L-phenylalanine residue, resp.A stands for a D-amino acid residue having a lower alkyl group or a lower thioalkyl group as side chain, andB stands for an amino group or an L-proline amide moiety,and their pharmaceutically acceptable salts. These compounds can be prepared from peptides containing terminal amino group corresponding in amino acid sequence by transforming the terminal amino group to guanidino group in a known way and, if desired, by forming a salt with a pharmaceutically acceptable acid.The novel compounds of the general formula I possess valuable morphine-like (enkephalin-like) opiate activities.