title: Synthesis and C(2) -symmetric structure of a cyclotetrapeptide composed of anthranilic acid and leucine.
abstract: A chiral cyclotetrapeptide (1) was synthesized from 2-nitrobenzoic acid and leucine. A single-crystal X-ray of the compound revealed a C(2) -symmetric bowl-shaped structure. The cyclic compound had a unique hydrogen-bonding network composed of three-centered hydrogen bonds and bifurcated hydrogen bonds between NH and CO of anthranilic residue. The NMR spectra and molecular modeling of 1 also suggested the chiral bowl structure.
authors.affiliation: Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, Inageku, Chiba, Japan. akazome@faculty.chiba-u.jp
authors.forename: Motohiro
authors.initials: M
authors.lastname: Akazome
authors.forename: Masashi
authors.initials: M
authors.lastname: Enzu
authors.forename: Koji
authors.initials: K
authors.lastname: Takagi
authors.forename: Shoji
authors.initials: S
authors.lastname: Matsumoto
mesh_terms: D006860:Hydrogen Bonding; D007930:Leucine / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D009842:Oligopeptides / Q000138:chemical synthesis* / Q000737:chemistry*; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism; D062367:ortho-Aminobenzoates / Q000737:chemistry*
chemical_list: D009842:Oligopeptides; D010456:Peptides, Cyclic; D062367:ortho-Aminobenzoates; C031385:anthranilic acid; D007930:Leucine