Liquid chromatographic resolution of biphenyl dimethyl dicarboxylate (DDB)and its analogues on a chiral stationary phase

Racemic biphenyl dimethyl dicarboxylate (DDB) and its analogues have been s uccessfully resolved on a commercial HPLC chiral column, (3R,4S)-Whelk-O 1. In general, cyclic amide analogues of DDB, which were derived from pyrroli dine or piperidine, showed greater enantioselectivity and greater retention than the corresponding N,N-dialkylamide or N-alkyl amide or ester analogue s. From these results, it was concluded that the carbonyl oxygen of the DDB analogues plays an important role as a hydrogen bond acceptor, though the steric bulkiness of the amide functionality of DDB analogues may be another factor governing chiral recognition. The conformational stability of the t wo enantiomer of DDB and its analogues was also found to be high enough for the two enantiomers to be resolvable on (3R,4S)-Whelk-O 1.