Preparation of a New β-Cyclodextrin-bonded Chiral Stationary Phase with Thiocarbamated Benzamide Spacer for HPLC

A new β-cyclodextrin-bonded chiral stationary phase (TCDP) with a thiocarbamated benzamide spacer was prepared and evaluated on HPLC by separating a series of chiral pesticides and drugs. TCDP resolved all 24 analytes (11 triazoles, 8 flavanones and 5 β-blockers), and 18 of them were completely separated. The enantioresolution ranges were 1.45 - 3.33 for triazoles, 0.35 - 2.45 for flavanones and 1.26 - 1.58 for β-blockers. Among them the best resolution of tebuconazole was up to 3.33 within 13 min. Bitertanol (two chiral centers) and triticonazole with cis/trans isomers were separated into four peaks, respectively. TCDP could also completely resolve myclobutanil (Rs = 1.68), which was difficult to be separated on other CD-CSPs. Common CDSP only resolved a few analytes. The results showed that the thiocarbamated benzamide spacer of TCDP may provide a synergistic effect of hydrogen bonding and coordination. The spacer deserved full utilization, by which may avoid troublesome derivatization at low cost.