Modified d-retro cyclic hexapeptide somatostatin analogs, process for their preparation and pharmaceutical compositions containing them.

摘要

The compounds are best summarized by formula:

wherein
Y is (CH2)m wherein m is 0, 1 or 2 or sulfur such that the sulfur may be in any position along the chain;
R1 and R2 are independently loweralkyl, benzyl, substituted benzyl where the substituent may be one or two of loweralkyl, halogen, hydroxy, amino, nitro or loweralkoxy; and loweralkyl substituted with a 5- or 6-membered hetercyclic ring;
R3 is 3-indolylmethyl or substituted 3-indolylmethyl wherein the substituent may be loweralkyl, loweralkoxy, or halogen;
R4 is loweralkyl, hydroxyloweralkyl, benzyl, carboxyloweralkyl, aminoloweralkyl or substituted benzyl wherein the substituent may be loweralkyl, loweralkoxy, hydroxy, halogen, amino or nitro;
R5 is hydrogen, loweralkyl, benzyl, or substituted benzyl wherein the substituent is loweralkyl, loweralkoxy, hydroxy, halogen, amino or nitro; and the two asymmetric centers marked with an asterisk (*) may be either D or L, provided the two centers of asymmetry are not the same, while the other asymmetric centers are D.
The term "loweralkyl" when used in the instant application is intended to represent those alkyl groups either straight or branched chain, which have from 1-5 carbon atoms. Examples of such alkyl groups are methyl, ethyl, propyl, iso-propyl, butyl, sec-butyl, pentyl and the like.