Enantiomeric separation by HPLC of 1,4 dihydropyridines with vancomycin as chiral selector

The macrocyclic antibiotics represent a relatively new class of chiral
selectors in CE, HPLC, and TLC. We have examined the use of the macrocyclic antibiotic
vancomycin as a chiral selector in HPLC for the separation of 1,4-dihydropyridines
(DHPs) calcium antagonists (CAs). Chromatographic data of six 1,4-dihydropyridine
calcium channel blockers obtained on the vancomycin chiral stationary phase (Chirobiotic
V) were compared with those obtained on an 1-acid glycoprotein (AGP) HPLC
stationary phase. Optimization of pH and organic modifier was carried out in order to
modulate the retention properties of each system. All chiral neutral DHPs were resolved
on the AGP column, whereas on Chirobiotic V only basic DHPs showed a split peak. The
analytical chromatographic procedure on Chirobiotic V proved suitable for semipreparative
separation, since the separation factor on the analytical column was high enough to
obtain pure enantiomers with high yields.