New vitamin K3 (menadione) analogues: synthesis, characterization, antioxidant and catalase inhibition activities

Abstract

In this study, derivatives of new vitamin K3 were synthesized by the reactions of 2-methyl-1,4-naphthoquinone1with some heterocyclic ring substituted nucleophiles: 1-piperonylpiperazine2, 1-(2-furoyl)piperazine5, 1-(2-aminoethyl)piperidine8, 1-(2-aminoethyl)pyrrolidine10and 2,6-dimethyl morpholine12in chloroform/triethylamine (TEA) or ethanol at room temperature. Their structures were characterized by Fourier transform infrared spectroscopy (FT-IR),H-1 nuclear magnetic resonance (H-1 NMR), attached proton test nuclear magnetic resonance (APT-NMR) and mass spectrometry (MS). Newly synthesized vitamin K3 derivatives (3,4,6,7,9,11,13,14) have shown catalase inhibition activity and compound 13 has displayed remarkable potency against catalase enzyme. These compounds were also tested for their antioxidant capacity in vitro by CUPRAC method.