摘要 |
Analogs of oxytocin of general formula I <IMAGE> where all amino acids are L-isomers and X is phenylalanine or phenylalanine substituted in the p-position by alkyl, ethoxy, amino, substituted amino, or nitro group, suitable for medical applications, and a method for their preparation consisting in the cyclization of linear octapeptides of general formula II <IMAGE> where X has the aforesaid meaning and Act is a group activating the carboxylic group of S-carboxyethylhomocysteine residue, e.g. an active ester. Two methods may be used for the preparation of [2-p-aminophenylalanine] deamino-6-carba-oxytocin, either the reduction of [2-p-nitrophenylalanine]- deamino-6-carba-oxytocin or deprotection of [2-p- benzyloxycarbonylaminophenylalanine] deamino-6-carba-oxytocin. |