Water-induced switching of beta-structure to polyproline II conformation in the 4s-aminoproline polypeptide via H-bond rearrangement

TitleWater-induced switching of beta-structure to polyproline II conformation in the 4s-aminoproline polypeptide via H-bond rearrangement
Publication TypeJournal Article
Year of Publication2010
AuthorsSonar, MV, Ganesh, KN
JournalOrganic Letters
Volume12
Issue23
Pagination5390-5393
Date PublishedDEC
ISSN1523-7060
Abstract

4S-Aminoproline polypeptide 2 forms unusual beta-structure in trifluoroethanol that switches to the polyproline II (PPII) form in aqueous medium. while 4R-aminoproline peptide 1 retains PPII form in both solvents. This first instance of a polyproline derivative showing a beta-structure is attributed to competitive pH-dependent (4-NH3+/NH2) stereoelectronic effect (4R vs 4S) and the overriding importance of stercospecific intra/intermolecular H-bonding in (2,4)-cis-4S-aminoproline in contrast to (2,4)-trans-4R-aminoproline oligomers.
DOI10.1021/ol1021993
Type of Journal (Indian or Foreign)Foreign
Impact Factor (IF)5.250
Divison category: 
Organic Chemistry