Efficient synthesis of unnatural dipeptides based on cis-2,5-disubstituted pyrrolidine

Abstract

The well-defined unnatural dipeptides based on cis-2,5-disubstituted pyrrolidine backbone were synthesized from commercially available starting materials meso-diethyl-2,5-dibromoadipate, (S)-(-)-1-phenylethylamine, and phenylalanine. The configurations of all the chiral centers in these unnatural dipeptides are confirmed by X-ray crystal diffraction analysis.

Facile Synthesis of Novel Chiral Bicyclic Thioureas and Their Crystal Structures

“…In our previous research work [27,28], we established a facile synthetic route to enantiopure unsymmetric cis-2, 5-disubstituted pyrrolidines containing hydroxyl-diamino skeleton (Figure 1), and herein we wish to report an efficient synthesis of novel chiral bicyclic thioureas based on the skeleton of these enantiopure pyrrolidines.…”

“…Melting points are Goodness-of-fit on F 2 1.068 O2-H2---S2 2.329 O2-H2---S2 161. 28 uncorrected and expressed in degree Celsius. Optical rotations analyses were performed on a Perkin-Elmer Model 343 Polarimeter.…”