A convenient approach to synthesis of benzoxazol-2-ylglycine and benzothiazol-2-ylglycicne derivatives

Abstract

Introduction of pharmacophore heterocyclic moieties into the peptide chain is of particular interest because it results in a promising new bioregulators [1] with a significant anticonvulsant, neuropathic and analgesic activity [2–6], and also oxytocin antagonists [7]. However, the functionalization of α-amino acids with electron-acceptor heterocycles is a challenging task, due to their ease of decarboxylation. This substantially limits the use of such amino acids in peptide synthesis. In this work, we developed a convenient approach to the synthesis of glycine derivatives, which were modified at the α-position with benzoxazol-2-yl and benzothiazol-2-yl moieties. For the first time we used for this purpose available 2-phenyl-4-dichloromethylene-5(4H)-oxazolone [8], which was involved into the reactions sequence: I → III → V or VII. The reaction I → III has been previously described by an example of 2-aminothiophenol [9], and all the other reaction were investigated by us for the first time. The DOI: 10.1134/S1070363213060364