Turkish Journal of Chemistry, cilt.30, sa.4, ss.505-514, 2006 (SCI-Expanded)
The N-alkyl derivatisation and photochemical dimerisation of 3 o-, m-, and p-nitro substituted 4-azachalcones (1-3) yielded 3 new o-, m-, and p-nitro substituted (.E)-N-decyl-4-azachalconium bromides, (2E)-1-(2-nitrophenyl)-3-(N—decyl-4-pyridmium bromide)-2-propen-1-one (4), (2E)-1-(3-nitrophenyl)-3-(N-decyl-4-pyridinium bromide)-2-propen-1-one (5), and (2E)-1-(4-nitrophenyl)-3-(N-decyl-4-pyridinium bromide)-2-propen-1-one (6), and 3 new dimers in solution, $(1beta,2alpha)$-di-(3-nitrobenzoyl)-$(3beta,4alpha)$-di-(4-pyridinyl)cyclobutane (7), $(1beta,2alpha)$-di-(4-nitrobenzoyl)-$(3beta,4alpha)$-di-(4-pyridinyl)cyclobutane (8a), and $(1beta,2alpha)$-di-(4-nitrobenzoyl)-$(3beta,4alpha)$-di-(4-pyridinyl)cyclobutane (8b), stereoselectively. The monomeric compounds showed good antimicrobial activity against test micro-organisms. The most sensitive microorganisms were Gram-positive bacteria. The monomers also showed high antioxidant activity, while the dimerisation products 7-8a,b were less active. Compound 6 was found to have similar or even higher activity when compared to the standard antipxidants Trolox and vitamin C, respectively. The possible dimerisation products of compounds 1-3 were calculated theoretically. Experimental and theoretical calculations showed that5-truxinic type dimer is the most stable isomer.