Inducted axial chirality in the biphenyl core of the C(Super alpha)-tetrasubstituted alpha-amino acid residue Bip and subsequent propagation of chirality in (Bip)(Sub n)/Val oligopeptides

In the dipeptides Boc-Bip-L-Val-OMe and Boc-Bip-D-Val-OMe, and induced axial chiralityh in the biphenyl core of the Bip residue, a conformationally labile, proatropoisomeric C(super alpha, alpha)-disubstituted glycine, is observed by electronic CD and 1H NMR. The findings show that the chiral induction is significantly higher when the Val residue is located at the C-terminal position of Bip.