Abstract: The N-substituted dimeric cyclopeptide derivatives of formula ##STR1## in which A is a peptide residue having one to four amino acid residues; R.sup.1 is lower alkyl, phenyl or phenyl(lower)alkylene; R.sup.2 is lower alkyl, cyclo(lower)alkyl or lower alkoxycarbonyl(lower)alkylene; and R.sup.3 is a neutral amino acid side chain and a method for the preparation of the compounds of formula I are disclosed. The compounds of formula I are useful for treating microbial infections. Pharmaceutical compositions also are disclosed.

Abstract: The N-substituted cyclopeptide derivatives of formula I ##STR1## in which R.sup.1 is lower alkyl, R.sup.2 is lower alkyl or cyclo(lower)alkyl, R.sup.3 is a neutral amino acid side chain and Y is a peptide residue having three to nine amino acid residues and a method for the preparation of the compounds of formula I are disclosed. The compounds of formula I are useful antibacterial and antifungal agents. Pharmaceutical compositions also are disclosed.

Abstract: The N-substituted dimeric cyclopeptide derivatives of formula ##STR1## in which A is a peptide residue having one to four amino acid residues; R.sup.1 is lower alkyl, phenyl or pheny(lower) alkylene; R.sup.2 is lower alkyl, cyclo(lower)alkyl or lower alkoxycarbonyl(lower)alkylene; R.sup.3 is a neutral amino acid side chain and a method for the preparation of the compounds of formula I are disclosed. The compounds of formula I are useful for treating microbial infections. Pharmaceutical compositions also are disclosed.

Abstract: The N-substituted cyclopeptide derivatives of formula I ##STR1## in which R.sup.1 is lower alkyl, R.sup.2 is lower alkyl or cyclo(lower)alkyl, R.sup.3 is a neutral amino acid side chain and Y is a peptide residue having three to nine amino acid residues and a method for the preparation of the compounds of formula I are disclosed. The compounds of formula I are useful antibacterial and antifungal agents. Pharmaceutical compositions also are disclosed.

Abstract: A process for preparing the LH- and FSH-releasing hormone of the formula Ih-- pyr-- His-- Trp-- Ser-- Tyr-- Gly-- Leu-- Arg-- Pro-- Gly-- NH.sub.

Abstract: Pyridylmethyl esters of N-(phenoxyalkanoyl)peptide derivatives are disclosed. The derivatives are characterized by having a phenoxyalkanoyl group and a pyridylmethyloxy group-joined together by a peptide group. They possess antihyperlipoproteinemic activity. In addition, methods for their preparation and use are disclosed.

Abstract: .alpha.-Hydrazinocarboxamide and .alpha.-(.alpha.'-acylhydrazino)-carboxamide derivatives of formula I ##STR1## in which R.sup.1 and R.sup.2 each are lower alkyl or R.sup.1 and R.sup.2 together with the nitrogen atom to which they are joined form a piperidino or morpholino radical; R.sup.3 is hydrogen, lower alkanoyl, benzoyl, p-nitrobenzoyl, p-aminobenzoyl, p-chlorobenzoyl, isocyanoacetyl, or protected amino acyl radicals, for example, N-formylglycyl or ##STR2## (N-carbobenzoxyglycylglycyl); R.sup.4 is lower alkyl, CHR.sup.7 COOR.sup.8 or CH.sub.2 CH.sub.2 COOR.sup.8 wherein R.sup.7 is hydrogen or phenyl and R.sup.8 is hydrogen or lower alkyl; R.sup.5 is hydrogen or lower alkyl; or R.sup.4 and R.sup.5 together with the carbon atom to which they are joined form a cyclohexylidene radical; and R.sup.6 is a cyclohexyl or CHR.sup.9 COY wherein R.sup.9 is hydrogen or benzyl and Y is hydroxyl, lower alkoxy or amine, with the provisos that when Y is hydroxyl then R.sup.

Abstract: Pyridylmethyl esters of N-(phenoxyalkanoyl)peptide derivatives are disclosed. The derivatives are characterized by having a phenoxyalkanoyl group and a pyridylmethyloxy group-joined together by a peptide group. They possess antihyperlipoproteinemic activity. In addition, methods for their preparation and use are disclosed.

Abstract: A process for preparing the LH- and FSH-releasing hormone of the formula Ih--pyr--His--Trp--Ser--Tyr--Gly--Leu--Arg--Pro--Gly--NH.sub.2which is isolated as the hydrochloride salt and optionally converted to other pharmaceutically acceptable salts or to pharmaceutically acceptable metal complexes.

Abstract: The tripeptide derivatives of formulaH--L--Pro--N(R.sup.1)CH(R.sup.2)CO--Y--R.sup.3 (1)in which R.sup.1 is hydrogen, lower alkyl or NR.sup.4 R.sup.5 wherein R.sup.4 and R.sup.5 each are lower alkyl, R.sup.2 is hydrogen or lower alkyl, R.sup.3 is amino, lower alkylamino, di(lower)alkylamino or amino(lower)alkylamino and Y is one of the amino acid residues Gly or D-Ala with the proviso that when R' is NR.sup.4 R.sup.5 wherein R.sup.4 and R.sup.5 are as defined herein and R.sup.2 and Y are as defined herein, R.sup.3 is lower alkylamino, di(lower)alkylamino or amino(lower)alkylamino, .Iadd.and with the further proviso that when R.sup.1 is hydrogen, R.sup.2 is hydrogen or lower alkyl and Y is Gly then R.sup.3 is amino(lower)alkylamino, .Iaddend.and a method for their preparation are disclosed. The tripeptide derivatives of formula 1 possess central nervous system activity and methods for their use are given.