Synthesis, N-alkyl and dimerization derivatives and biological activities of methoxy substituted azachalcones

In this work, methoxy substituted azachalcones (1-9), which are analogs of the natural chalcone-type compounds, their N-octyl, N-decyl and N-dodecyl derivatives (10-27) and photochemical [2+2] cyclo addition products (28-39) were synthesized. Although compounds 1, 4, 7-9 were found to be known, compounds 2, 3, 5, 6, 10-39 were synthesized for the first time in this study. Identification of compounds 1-39 were done by spectroscopic methods using NMR (1H NMR, 13C NMR, APT, COSY), FT-IR, UV, LC-MS/MS and elemental analysis techniques. In order to explain the photochemical reactions, theoretical calculations were performed by using Hyperchem 7.5 programme, and products were found to be in harmony with the results obtained from the calculations.In the antimicrobial activity studies of compounds 1-39, compounds 1-9 and 22 showed antimicrobial activity against Gram-positive bacteria and fungi. Compounds 10-21 and 23-27, which are N-octyl, N-decyl, and N-dodecyl derivatives, showed high antimicrobial activities against all test microorganisms, and it is seen that activities were increased with carbon chain elongation. Photochemical dimer products 28-39 were not effective against the tested microorganisms. Only compound 38 showed activity against Gram positive bacteria.As a result of antioxidant activity studies on the compounds 1-27, it is estimated that antioxidant activity of these compounds were not very good. The best activity was determined with compound 23.