The Bip method, based on the induced circular dichroism of a flexible biphenyl probe in terminally protected -Bip-Xaa*- dipeptides, for assignment of the absolute configuration of beta-amino acids.
An induced axial chirality of the biphenyl core of the Bip (2',1':1,2;1'',2'':3,4-dibenzcyclohepta-1,3-diene-6-amino-6-carboxylic acid) residue in the terminally protected dipeptides Boc-Bip-beta-Xaa*-OMe (beta-Xaa* = L-beta(3)-HAla, L-beta(3)-HVal, L-beta(3)-HLeu, L-beta(3)-HPro, trans-(1S,2S)-ACHC, trans-(1R,2R)-ACHC, trans-(1S,2S)-ACPC, trans-(1R,2R)-ACPC) resulted in an induced circular dichroism, revealing the usefulness of the Bip method for a reliable and fast assignment of the absolute configuration of chiral beta-amino acids. Remarkably, the Bip method was also applied to the unique spin-labeled, cyclic, beta-amino acids cis/trans-beta-TOAC and trans-POAC. In particular, this study allowed the assignment of the unknown absolute configurations of the enantiomers of the latter compound.
Dutot
Laurence
L
ILV, UMR CNRS 8180, University of Versailles, 78035 Versailles, France.
Wright
Karen
K
Gaucher
Anne
A
Wakselman
Michel
M
Mazaleyrat
Jean-Paul
JP
De Zotti
Marta
M
Peggion
Cristina
C
Formaggio
Fernando
F
Toniolo
Claudio
C
D000596:Amino Acids / Q000737:chemistry*; D001713:Biphenyl Compounds / Q000737:chemistry*; D002942:Circular Dichroism / Q000379:methods*; D004151:Dipeptides / Q000737:chemistry*; D008968:Molecular Conformation; D011487:Protein Conformation; D017550:Spectroscopy, Fourier Transform Infrared; D013237:Stereoisomerism
D000596:Amino Acids; D001713:Biphenyl Compounds; D004151:Dipeptides