The new series of N-, S-, O-substituted 1,4-naphthoquinone and S-, O-substituted 1,4-benzoquinone compounds were synthesized via vinylic substitution. Compounds 3 and 4 were synthesized from the reaction of 1 with 2. Compounds 6, 7 and 8 were synthesized from reaction of 1 with 5. Compounds 10 and 11 were obtained from the reaction of 1 with 9. Compounds 13 and 14 were synthesized from the reaction of 1 with 12. Compounds 16 and 17 were obtained from the reaction of 15 with 2. Photochemical and electrochemical properties of N-, S-, O-substituted quninone compounds were determined by using fluorescence spectroscopy and cyclic voltammetry. Crystal structure of 2-(7-sulphanyl-4-methyl-coumarinyl)-3-(1-ethoxy)-1,4-naphthoquinone 13 was determined by X-ray diffraction method.

Polyhalogenated-2-nitro-1, 3-butadienes are important synthetic precursors for a variety of polyfunctionalized bioactive heterocycles. Herein, we report the reactions of 1, 1, 3, 4, 4-pentachloro-2-nitro-1, 3-butadiene 1 and 4-bromo-1, 1, 3, 4-tetrachloro-2-nitro-1, 3-butadiene 2 with amino and thiol containing nucleophiles to obtain highly functionalized (E)-polyhalodiene-2-nitro-1, 3-butadiene derivatives. Most of these reactions were found to be highly selective resulting in good to high yields of the products. All new compounds have been characterized by nuclear magnetic resonance spectroscopy (NMR), mass spectrometry (MS) and Fourier transform infrared spectroscopy (FT-IR) spectroscopic data. Single crystal X-ray structure analysis of compound 8c is reported.

In this study, derivatives of new vitamin K3 were synthesized by the reactions of 2-methyl-1,4-naphthoquinone 1 with some heterocyclic ring substituted nucleophiles: 1-piperonylpiperazine 2, 1-(2-furoyl)piperazine 5, 1-(2-aminoethyl)piperidine 8, 1-(2-aminoethyl)pyrrolidine 10 and 2,6-dimethyl morpholine 12 in chloroform/triethylamine (TEA) or ethanol at room temperature. Their structures were characterized by Fourier transform infrared spectroscopy (FT-IR), ¹H nuclear magnetic resonance (¹H NMR),attached proton test nuclear magnetic resonance (APT-NMR) and mass spectrometry (MS). Newly synthesizedvitamin 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