Tryptophan-derived NK1 antagonists: Conformationally constrained heterocyclic bioisosteres of the ester linkage

Article abstract of DOI:10.1021/jm00006a011

The 3,5-bis(trifluoromethyl)benzyl ester of N-acetyl-L-tryptophan 1 (L- 732,138) has been identified previously as a potent and selective substance P receptor antagonist. A series of analogs which introduced a 6-membered heterocyclic ring into the backbon