title: Robust turn structures in α3β cyclic tetrapeptides induced and controlled by carbo-β3 amino acid.
abstract: Designing cyclic tetrapeptides (CTPs), which fold into desired structures, is often a challenging task. While it is difficult to synthesize them, they are also prone to adopt multiple conformations. In this paper we report the synthesis and conformational studies of CTP mimics, having nonconstrained α(3)β motif, that exhibit stable β- and γ-turn structures. We also demonstrate the transformation of β-turn to γ-turn structure in similar CTPs by inverting the chirality of β(3) carbon in C-linked-carbo-β(3)-amino acid (Caa) from R to S.
authors.affiliation: Division of Medicinal and Process Chemistry, SAIF, Central Drug Research Institute, Lucknow-226001, India.
authors.forename: Anindra
authors.initials: A
authors.lastname: Sharma
authors.forename: Shrikant
authors.initials: S
authors.lastname: Sharma
authors.forename: Rama P
authors.initials: RP
authors.lastname: Tripathi
authors.forename: Ravi Sankar
authors.initials: RS
authors.lastname: Ampapathi
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D015195:Drug Design; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D010456:Peptides, Cyclic / Q000138:chemical synthesis*; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary
chemical_list: D000596:Amino Acids; D010456:Peptides, Cyclic