HPLC enantiomeric resolution of novel aromatase inhibitors on cellulose- and amylose-based chiral stationary phases under reversed phase mode

The chiral resolution of seven aromatase inhibitors (four triazole derivatives (Ia, Ib, Ic, and Id) and three tetrazole derivatives (IIa, IIb, and IIc)) was achieved on Chiralcel OJ-R cellulose tris (4-methyl benzoate)], Chiralcel OD-RH cellulose tris (3,5-dimethylphenyl carbamate)], and Chiralpak AD-RH amylose tris (3,5-dimethylphenyl carbamate)] chiral stationary phases. The mobile phases used were A: 2-PrOH-MeCN (90:10, v/v); B: 2-PrOH-MeCN (50:50, v/v); C: MeCN-H(2)O (50:50, v/v); D: MeCN-H(2)O (80:20, v/v); and E: MeCN-H(2)O (95:05, v/v). The flow rate was 0.5 mL/min for all the mobile phases. The resolution capability of these chiral stationary phases were in the order Chiralpak AD-RH > Chiralcel OD-RH > Chiralcel OJ-R. The values of alpha and Rs of the resolved enantiomers of the aromatase inhibitors varied from 1.02-5.63 and 1. 12-6.72, respectively.