Synthesis and comparative molecular field analysis (CoMFA) of argentatin B derivatives as growth inhibitors of human cancer cell lines.

Synthesis, characterization, anticancer activity, and comparative molecular field analysis (CoMFA) of 14 argentatin B (1) analogs are described. The effect of argentatin B derivatives on the growth of K562 (leukemia), PC-3 (prostate), U251 (CNS), and HCT-15 (colon) human cancer cell lines was determined using the sulforhodamine B test. The most active compound in this series, 2-formyl-(16beta,24R)-16,24-epoxy-25-hydroxycycloart-1-en-3-one (12), was about 35-50 times more potent than argentatin B (1).

3D-QSAR, synthesis, and antimicrobial activity of 1-alkylpyridinium compounds as potential agents to improve food safety.

Cetylpyridinium chloride (CPC), an alkylpyridinium compound has been recently approved by the US Food and Drug Administration to reduce bacterial contamination in poultry. Although CPC is very effective and has a very good safety record, its relatively high lipophilicity may limit its use in high fat containing foods such as beef. In this study we present the CoMFA analysis (3D-QSAR) of the antimicrobial activity of 60 N-alkylpyridinium compounds against different bacteria.

Comparison of CoMFA models for Salmonella typhimurium TA98, TA100, TA98 + S9 and TA100 + S9 mutagenicity of nitroaromatics.

Comparative Molecular Field Analysis (CoMFA) was applied to a comprehensive data set of heterogeneous nitroaromatics tested in Salmonella typhimurium TA98 and TA100 with and without S9 microsomal activation. The four CoMFA models developed agree with postulated mechanisms of mutagenicity, and explain over 70% of the corresponding mutagenic variance The standard deviation coefficient contours common in the four models included high electronic density regions equivalent to C4-C5 in the pyrene ring, and an electron deficient site equivalent to C6. These areas are associated with high mutagenicity.

Regiospecificity of peroxyl radical addition to (E)-retinoic acid.

The regiochemistry of peroxyl radical addition to (E)-retinoic acid (RA) was investigated. Peroxyl radicals, generated by reaction of 13-hydroperoxy-(9Z,11E)-octadecadienoic acid with hydroxo(porphyrinato)iron(III) in Tween 20 micelles, were reacted with RA. The major, and virtually exclusive, RA oxidation product was 5,6-epoxy-RA which was identified on the basis of cochromatography with the synthetic synthetic oxirane (in a reverse phase HPLC system), electronic absorption spectroscopy, high-field 1H-NMR, and EI mass spectrometry.

Nonenzymatic reduction of tetrachloro-1, 4-benzoquinone by reduced nicotinamide adenine dinucleotide phosphate in an aqueous system.

NADPH was shown to reduce tetrachloro-1,4-benzoquinone (TCBQ) to tetrachloro-1,4-benzene diol which was identified on the basis of cochromatography with synthetic standard in a reverse phase HPLC system, electronic absorption spectroscopy, and mass spectrometry. Conversely, NADPH was shown to undergo TCBQ-dependent oxidation as evidenced by uv spectroscopic analysis. ESR spectroscopy demonstrated that NADPH-dependent reduction of TCBQ proceeds through the intermediacy of a semiquinone radical intermediate.