Separation of Biologically Active Isomers of (E)‐N‐Meta‐ and Para‐Nitroazastilbenes by the HPLC Technique

Abstract

Results of investigations concerning the chromatography of bromides of (E)‐N‐m‐ and p‐nitrobenzyl‐4′‐hydroxy‐3′‐methoxystilbazoles‐4 are presented. Analyzed compounds, similarly to other azastilbene halogenides show antimicrobial activity. Optimal conditions of chromatographic separation and determination of two mentioned isomers have been elaborated. In the investigation three stationary phases (octadecyl, octyl, and naphthylpropyl), two mobile phases (acetonitrile, dichloromethane) and various flow were considered. The best selectivity and the highest separation factor, α=1.74, were obtained using a naphthylpropyl column and 100% acetonitrile, as the mobile phase. An application of an octadecyl phase, recommended by numerous analysts as standard, allowed only the observation of an existence of two compounds, but did not yield satisfactory results.