Jarmila Chovancová

Synthesis, antimicrobial activity and bleaching effect of some reaction products of 4-oxo-4H-benzopyran-3-carboxaldehydes with aminobenzothiazoles and hydrazides

The synthesis of the biologically active novel systems derived from reaction of 3-formylchromones with three types of amino derivatives, 6-R2-2-aminobenzothiazoles, 6-amino-2-R3-thiobenzothiazoles and hydrazide derivatives (derived from cyanoacetic, isonicotine, salicylic and gallic acids) was carried out. The structures of the prepared compounds have been proved by elemental analysis, 1H NMR and IR spectra. Antimicrobial activity was studied against the following microorganisms--bacteria G+ (Staphylococcus aureus 29/58, Bacillus subtilis 18/66), G- (Escherichia coli 326/71, Pseudomonas aeruginosa); yeasts: Candida albicans, Saccharomyces cerevisiae; moulds: Microsporum gypseum, Aspergillus niger, Scopulariopsis brevicaulis; and against typical and atypical mycobacteria: Mycobacterium tuberculosis (H37Rv), Mycobacterium kansasii (PFG 8), Mycobacterium avium (My 80/72), Mycobacterium fortuitum (1021). The hereditary bleaching effect on the plastid system of Euglena gracilis, a unique phenomenon of the biological activity of chromone derivatives, is reported. The bleaching test on E. gracilis is used for detecting extranuclear mutations.

Reaction of 3-formylchromones with aromatic amino carboxylic acids

Abstract 2-Alkoxy-3-(arylaminomethylene)chroman-4-ones and 3-(aryliminomethyl)chromones were prepared by acid catalyzed reaction of 3-formylchromones with aromatic amino carboxylic acids in alcoholic reaction media. The results of the kinetic study have confirmed that 3-(aryliminomethyl)chromones are formed from 2-alkoxy-3-(arylaminomethylene)chroman-4-ones. The dependence of the reaction rate on reactant structure, the reaction media and the concentration of catalyst has been studied. In contrast to the alcoholic media reaction, the same reaction in dry aprotic reaction media yielded only 2-hydroxy-3-(arylaminomethylene)chroman-4-ones. No 3-(aryliminomethyl)chromones were isolated in that case.

MICROWAVES ASSISTED GABRIEL SYNTHESIS OF PHTHALIDES

Abstract Cesium acetate was found to be the best catalyst for the synthesis of 3-benzylidenephthalide from phthalic anhydride and phenylacetic acid. Reasonable to good yields of different 3-arylmethylenephthalides were isolated from the microwave Gabriel synthesis, even when phenylthio- and 2-(3-)thienyl- acetic acids were used as the starting material.

Evaluation of Effect of Microwave Irradiation on Syntheses and Reactions of Some New 3-Acyl-methylchromones

The 3-Acyl-2-R-methylchromones (R = H, ArO, C6H4(CO)2N) were prepared in good yields by different methods from 2-hydroxyaroylacetone derivatives. Some subsequent reactions of these compounds with hydroxylamine and 3-formylchromones are described. The effect of microwave irradation on some condensation reactions was studied.