| 摘要 |
<p>PURPOSE:To obtain the titled substance having physioloigical activity simply and in high yield, by removing the protecting group of N-(N'-protecting alpha-amino acid)-N-carboxyl-alpha,beta-dehydro-alpha-amino acid anhydride with a given reagent in the presence of both a given solvent and a base. CONSTITUTION:The protecting group X1 (e.g. t-butoxycarbonyl group) of a compound shown by formula I (R1 and R2 are H, carboxyl group properly replaced with protecting group which is slightly eliminated under an acidic condition, alkyl group, etc., with the proviso that R1 and R2 are not H at the same time; R3 is H, carbamido properly replaced with a protecting group which is slightly eliminated under an acidic condition, carboxyl, etc.; X1 is alpha-amino group-protecting group of alpha-amino acid) is removed with a given reagent (preferably solvent containing hydrogen chloride gas) in a given solvent (preferably dichloromethane) and reacted in the presence of a given base (preferably N- methylmorpholine) to give a compound shown by formula II.</p> |
