Conformational studies of Phe-rich foldamers by VCD spectroscopy and ab initio calculations.

Content Provider	Semantic Scholar
Author	Longhi, Giovanna Abbate, Sergio Lebon, Fr'ed'eric Castellucci, Nicola Sabatino, Piera. Tomasini, Claudia
Copyright Year	2012
Abstract	Employing VCD spectroscopy, we demonstrate that the structural behavior of the oligomers Boc-(L-Phe-L-Oxd)(n)-OBn is similar from n = 2 to n = 6; ab initio calculations for the n = 1 case provide physical insight into the conformational properties. Further information is gained by IR, (1)H NMR, and ECD spectroscopies. ECD spectra suggest the presence of different conformations between n = 1 on one side and longer chain foldamers on the other side. VCD and absorption IR spectra in methanol solutions can be interpreted as indicative of a PPII structure. In the case of Boc-L-Phe-L-Oxd-OBn, VCD spectra in CCl(4) and detailed DFT computational analysis allow one to demonstrate that the most populated conformers exhibit backbone dihedral angles similar to those of a PPII geometry. This is a remarkable outcome, as we had previously demonstrated that the Boc-(L-Ala-D-Oxd)(n)-OBn series folds in a β-band ribbon spiral that is a subtype of the 3(10) helix.
Starting Page	333
Ending Page	337
Page Count	5
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://www.canli.dicp.ac.cn/Gruop%20Seminars%20Pdf/20120721-byzhang.pdf?origin=publication_detail
PubMed reference number	22716234v1
Alternate Webpage(s)	https://doi.org/10.1021/jo300688n
DOI	10.1021/jo300688n
Journal	The Journal of organic chemistry
Volume Number	77
Issue Number	14
Language	English
Access Restriction	Open
Subject Keyword	Alanine Bortezomib/Cyclophosphamide/Dexamethasone Regimen Gain Methanol Phenylalanine Solutions Vertebral column butyloxycarbonyl-phenylalanyl-leucyl-phenylalanyl-leucyl-phenylalanine
Content Type	Text
Resource Type	Article