Dilute mixtures of hexanal in synthetic air (up to 100 ppm) were photolyzed with fluorescent UV lamps (275-380 nm) in air at 298 K. The main photooxidation products, identified and quantitatively analyzed by FTIR spectroscopy, were butene, CO, vinylalcohol and ethanal. The photolysis rates and the absolute quantum yield Φ were found to be slightly dependent on the total pressure. At 100 Torr, Φ100 = 0.43 ± 0.02, whereas at 700 Torr the total quantum yield was Φ700 = 0.38 ± 0.02. These results may be explained by the collisional deactivations of photoexcited molecules. Two decomposition channels were identified: the radical channel C5H11CHO → C5H11 + HCO, and the molecular channel C5H11CHO → C4H8 + CH2=CHOH, having the relative yields of 27 and 73 % at 700 Torr. The product CH2=CHOH tautomerizes to ethanal.

New computational insights into the mechanism of the Boyland-Sims oxidation of arylamines with peroxydisulfate (S(2)O(8)(2-)) in an alkaline aqueous solution are presented. The key role of arylnitrenium cations, in the case of primary and secondary arylamines, and arylamine dications and immonium cations, in the case of tertiary arylamines, in the formation of corresponding o-aminoaryl sulfates, as prevalent soluble products, and oligoarylamines, as prevalent insoluble products, is proposed on the basis of the AM1 and RM1 computational study of the Boyland-Sims oxidation of aniline, ring-substituted (2-methylaniline, 3-methylaniline, 4-methylaniline, 2,6-dimethylaniline, anthranilic acid, 4-aminobenzoic acid, sulfanilic acid, sulfanilamide, 4-phenylaniline, 4-bromoaniline, 3-chloroaniline, and 2-nitroaniline) and N-substituted anilines (N-methylaniline, diphenylamine, and N,N-dimethylaniline). Arylnitrenium cations and sulfate anions (SO(4)(2-)) are generated by rate-determining two-electron oxidation of primary and secondary arylamines with S(2)O(8)(2-), while arylamine dications/immonium cations and SO(4)(2-) are initially formed by two-electron oxidation of tertiary arylamines with S(2)O(8)(2-). The subsequent regioselectivity-determining reaction of arylnitrenium cations/arylamine dications/immonium cations and SO(4)(2-), within the solvent cage, is computationally found to lead to the prevalent formation of o-aminoaryl sulfates. The formation of insoluble precipitates during the Boyland-Sims oxidation of arylamines was also computationally studied.

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The bacteriostatic activity of some of alkyl substituted (E)-?-(benzoyl)acrylic acids was shown earlier. The aim of this study was to investigate the antiproliferative action of 19 alkyl-, or halogeno-, or methoxy-, or acetamido-substituted (E)-?-(benzoyl)acrylic acids, against human cervix carcinoma, HeLa, cells. Target HeLa cells were continuously treated with increasing concentrations of substituted (E)-?-(benzoyl)acrylic acids during two days. The MTT test was used for assessment of the antiproliferative action of this group of compounds. Treatment of HeLa cells with 4-methyl-, 4-fluoro-, 4-chloro-, 4-bromo- and 4-methoxy- derivatives of (E)-?-(benzoyl) acrylic acid leads to the expression of cytostatic activity against HeLa cells (IC50 were in the range from 31.40 mM). Their antiproliferative action was less than that of the basic compound (E)-?-(benzoyl)acrylic acid whose IC50 was 28.5 mM. The 3,4-di-methyl-, 2,4-dimethyl- and 2,5-dimethyl-derivatives as well as the 4-ethyl- and 3,4-di-chloro- and 2,4-dichloro-derivatives, have stronger cytostatic activity than the correspoding monosubstituted and parent compound. Their IC50 were 18.5 mM; 17.5 mM; 17.0 mM; 17.5 mM; 22.0 mMand 18 mM, respectively. The 4-iso-propyl- and 4-n-butyl- derivatives exerted higher cytostatic activity than the compounds with a lower number of methylene -CH2. groups in the substitutent. Their IC50 were 14.5 mM and 6.5 mM respectively. The 2,5-di-iso-propyl- and 4-tert-butyl-derivatives expressed the most strong antiproliferative action against the investigated HeLa cells, IC50 being 4.5 mM and 5.5 mM, respectively. The investigated compounds affected the survival of HeLa cells, expressing a strong structure-activity relationship of the Hansch type.