title: Fast and efficient peptide bond formation using bis-[alpha,alpha-bis(trifluoromethyl)-benzyloxy]diphenylsulfur. Part I.
abstract: This study towards the development of sulfurane-based coupling agents shows that bis-[alpha,alpha-bis(trifluoromethyl)-benzyloxy]diphenylsulfur (BTBDS) can facilitate rapid amide bond formation between Nalpha-urethane-protected l-amino acids and l-phenylalanine ethyl ester in the absence of an external base. The corresponding dipeptide esters were obtained in excellent yields and with no detectable racemization, as judged by analysis of the formed dipeptides by chiral-phase HPLC. In addition, BTBDS-mediated condensation of benzoyl-l-phenylalanine with l-phenylalanine ethyl ester was also investigated. The results indicate that sulfuranes can be useful for application in racemization-sensitive systems, such as segment condensation.
authors.affiliation: Division of Organic and Bioorganic Chemistry, MBB, Scheele Laboratory, Karolinska Institute, Stockholm, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Slaitas
authors.forename: E
authors.initials: E
authors.lastname: Yeheskiely
mesh_terms: D000577:Amides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010455:Peptides / Q000138:chemical synthesis* / Q000737:chemistry*; D013457:Sulfur Compounds / Q000737:chemistry*
chemical_list: D000577:Amides; D010455:Peptides; D013457:Sulfur Compounds; C473827:bis-(alpha,alpha-bis(trifluoromethyl)-benzyloxy)diphenylsulfur