Convenient green preparation of dipeptides using unprotected α-amino acids
摘要:
Dipeptides and amides were obtained in high yields from N-carbobenzyloxy a-amino acids and 3-phenylpropanoic acid with unprotected a-amino acids via the corresponding mixed carbonic carboxylic anhydrides using ethyl chloroformate and triethylamine by an ecological and convenient method in which the protection of C-terminals is not needed. (C) 2016 Elsevier Ltd. All rights reserved.
The coupling reactions of 3-phenylpropanoic acid and N-carboxybenzyl α-aminoacids with unprotected α-aminoacids containing hydrophilic side chains such as aliphatic alcohol, aromatic alcohol, thiol, carboxylic acid, and amide afforded the corresponding amides in 66–96% yield without racemization via the corresponding mixed carbonic carboxylic anhydrides under basic conditions through an ecological
Condensation of carboxylic acids 1 and 5 with unprotected α-amino acids 2 via activation by ethyl chloroformate and triethylamine proceeded effectively to afford the corresponding amides in 50–99% yields. Tripeptide 7c was obtained in 42% yield from the dipeptide 6c in a similar manner.
Convenient Peptide Synthesis Using Unprotected α-Amino Acids Containing Another Hydrophilic Moiety under Basic Conditions
作者:Takuya Noguchi、Seunghee Jung、Nobuyuki Imai
DOI:10.1246/cl.2012.577
日期:2012.6.5
Carboxylic acids 1 and 7 reacted effectively with unprotected α-amino acids 2 containing another hydrophilic moiety under basic conditions via activation by ethyl chloroformate and triethylamine to afford the corresponding amides in 74–99% yields.