Synthesis and RP HPLC studies of biologically active semicarbazides and their cyclic analogues 1,2,4-triazol-3-ones

Monika Pitucha; Joanna Matysiak; Bogdan Senczyna

doi:10.1007/s00706-011-0715-z

Synthesis and RP HPLC studies of biologically active semicarbazides and their cyclic analogues 1,2,4-triazol-3-ones

Monatsh Chem. 2012;143(4):657-667. doi: 10.1007/s00706-011-0715-z. Epub 2012 Jan 28.

Authors

Monika Pitucha¹, Joanna Matysiak², Bogdan Senczyna²

Affiliations

¹ Department of Organic Chemistry, Medical University of Lublin, Lublin, Poland.
² Department of Chemistry, University of Life Sciences in Lublin, Lublin, Poland.

Abstract

Abstract: The retention behaviour of semicarbazides and their cyclic analogues 1,2,4-triazol-3-ones, has been investigated by RP-8, RP-18 and IAM HPLC. The structures of new derivatives were proved by elemental analyses, IR, ¹H NMR and ¹³C NMR spectroscopy. The compounds showed regular retention behaviour in three chromatographic systems; their log k values decreased linearly with the increasing concentration of an organic modifier in the mobile phase. The ratio of the intercept (log k_w) to the slope of compounds is constant and the same for both groups of compounds on C18 and IAM stationary phases. Differences between log k_w values from the octadecyl stationary phase of corresponding cyclic and linear derivatives are constant, and they are related to the mechanism of synthesis of 1,2,4-triazol-3-ones from linear substrate semicarbazides, which was confirmed by modelling studies. Good correlations between log k_w parameters obtained by RP-8 or RP-18 and determined by the computational approach log P were found.

Keywords: 1,2,4-Triazol-3-one; IAM chromatography; Lipophilicity; RP HPLC; Semicarbazide.