New tetrapeptides, process for preparing them and the new intermediates thus obtained, their application as medicinal products and compositions containing them

摘要

The invention relates to new compounds of formula: <IMAGE> in which R represents a hydrogen atom or an alkyl radical containing 1 to 5 carbon atoms, X represents a L-phenylalanine, L-tyrosine or L-tryptophan residue, Y an L-histidine, L-arginine or L-lysine residue, U an L-leucine, L-alanine, L-valine or L-isoleucine residue, B represents a pyridyl radical and A a hydrogen atom or a group for protecting the amine functional group of X, in all their possible diastereoisomeric forms as well as their addition salts with acids. The subject of the invention is also a process for preparing the products of formula I and the new intermediates thus obtained, their application as medicinal products and compositions containing them.