title: A racemization test in peptide synthesis using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM).
abstract: Racemization of the C-terminal amino acid (Ala) has been studied in various solvents during coupling between 4-methoxybenzyloxycarbonyl (Z(OMe))-Gly-L-Ala-OH and phenylalanine benzyl ester (H-Phe-OBzl) with 4-(4,6-dimethoxy-1,3,5-thiazin-2-yl)-4-methylmorpholinium chloride (DMT-MM). The reaction occurred without substantial racemization in AcOEt, tetrahydrofuran (THF), N,N-dimethylformamide (DMF), CH3CN, and 2-PrOH, while a slight racemization was observed in dimethyl sulfoxide (DMSO), EtOH, and MeOH. The extent of racemization may correlate with the polarity of the solvents.
authors.affiliation: Faculty of Pharmaceutical Sciences and High Technology Research Center, Kobe Gakuin University, Japan. kunisima@kgu-p.pharm.kobegakuin.ac.jp
authors.forename: Munetaka
authors.initials: M
authors.lastname: Kunishima
authors.forename: Akiko
authors.initials: A
authors.lastname: Kitao
authors.forename: Chiho
authors.initials: C
authors.lastname: Kawachi
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Shin
authors.initials: S
authors.lastname: Iguchi
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Hioki
authors.forename: Shohei
authors.initials: S
authors.lastname: Tani
mesh_terms: D002851:Chromatography, High Pressure Liquid; D009025:Morpholines / Q000737:chemistry*; D009842:Oligopeptides / Q000138:chemical synthesis*; D012997:Solvents / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: C467606:4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride; D009025:Morpholines; D009842:Oligopeptides; D012997:Solvents