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Updated: Feb 14, 2026

Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile
Published on: October 30, 2018
Modifying oligoalanine conformation by replacement of amide to ester linkage
Takahiro Hongen1, Tohru Taniguchi1, Kenji Monde1
1Frontier Research Center for Advanced Material and Life Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan.
Abstract:
Oligo(lactic acid) is an ester-analogue of short oligoalanine sequence and adopts a rigid left-handed helical structure. In this study, oligo(lactic acid) was incorporated into oligoalanine sequences and their conformations were studied by vibrational circular dichroism and electronic circular dichroism spectroscopy. The results suggested that oligo(lactic acid) moiety in these sequences maintains a left-handed helix and increases the conformational propensity of the oligoalanine moiety to form a left-handed polyproline type II-like helix. The importance of the chirality of oligo(lactic acid) moiety for the oligoalanine conformation was also studied. The results obtained in this study should be useful in developing ester-containing oligopeptides that function better than normal peptides.
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