By stepwise synthesis from . the amino end 3-benzylthiopropionyl-tyrosyl-phenylalanine methyl ester (IV) was prepared, converted into the hydrazide (V) and azide and condensed with glutaminyl-asparaginyl-S-benzy1cysteine methyl ester. From the obtained pentapeptide ester derivative VI the hydrazide VII and the azide were prepared. The latter was coupled with prolyl-NY-tosylo-
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.