[Photochemical generation of the cation-radical of bacteriochlorophyll b and the anion-radical of bacteriochlorophyll b and bacteriopheophytin b, components of the photosynthesizing bacteria Rhodopseudomonas viridis]

The mechanism of photochemical redox reaction of bacteriochlorophyll b, bacteriopheophitin b was studied. The oxidation of bacteriochlorophyll b was carried out in ethanole by means of p-benzoquinone. In ESR spectra the singlet line with delta H = 8.4 gs and g = 2.0025 corresponded to cation-radical. The changes within the region of 400-500 nm, 500-600 nm and the band with the maximum at 685 nm corresponded to cation-radical in the absorption spectra. Photoreduction of bacteriochlorophyll b and bacteriopheophitin b was carried out in triet containing phenilhydrosin. Anion-radicals of bacteriochlorophyll b and bacteriopheophitin b observed in the ESR spectra had singlet form with weak and superthin structure and correspondently with delta H = 10 gs, delta H = 12 gs. The spectrophotometric characteristics of the above pigments were obtained.

[Impulse photoconductivity of solutions of chlorophyll and its analogs. II. Effect of medium polarity on the yield of ion-radicals during the photoxidation of chlorophyll a ]

The effect of the dielectric constant epsilon of the solvent on the yield delta n of ion-radicals during photooxidation of chlorophy-l a with n-benzoquinone was studied by the method of impulse photoconductivity. It was shown that in the studied range of dielectric constant valve (epsilon congruent to 5-25) delta n monotonously increased with an increase of epsilon the relationship delta n (epsilon) being of clearly pronounced S-like character with a bend in the region of epsilon congruent to 10. A half-quantitative explanation of the data obtained is presented.

Chemistry and pharmacology of naproxen

The need for a nonsteroidal anti-inflammatory agent effective in rheumatoid arthritis, osteoarthritis, gout, ankylosing spondylitis and related diseases with reduced side effects when compared to existing drugs led us to develop naproxen: d-2-(6'-methoxy-2'-naphthyl)-propionic acid. This new agent is a highly effective anti-inflammatory, analgetic, and antipyretic agent in the rodent administered orally. In a rat paw edema test for anti-inflammatory activity naproxen was 55 times more active than aspirin. Analgetic activity was assessed by three different assay procedures. In the mouse phenylquinone writhing test naproxen was 7 times as effective as aspirin. In the rat yeast-induced paw edema and the rat carrageenin paw edema analgetic assays the test compound was 10 and 20 times more effective than aspirin, respectively. A yeast-induced pyresis model in the rat indicated that naproxen was 22 times more potent than the standard aspirin. The relative potency of naproxen to phenylbutazone and indometacin is presented.

Effects of inducers and epoxide hydrase on the metabolism of benzo(a)pyrene by liver microsomes and a reconstituted system: analysis by high pressure liquid chromatography

The mobilities of 24 potential metabolites of benzo[a]pyrene were examined with high pressure liquid chromatography. Twelve phenols, five quinones, four dihydrodiols, and three oxides were studied. The chromatographic procedure employed allowed the separation and quantitation of benzopyrene metabolites into three major groups consisting of phenols, quinones, and dihydrodiols. Two of the benzopyrene oxides were unstable during chromatography, whereas the third oxide was more stable and chromatographed in the quinone fraction. Treatment of rats with phenobarbital or 3-methylcholanthrene enhanced the metabolism of benzopyrene by liver microsomes and altered the relative amounts of the various metabolites formed. In the absence of epoxide hydrase (EC 4.2.1.63), benzopyrene was metabolized primarily to phenols and quinones but was not appreciably metabolized to dihydrodiols by a solubilized, reconstituted cytochrome P-448 monooxygenase system. Addition of partially purified epoxide hydrase resulted in the formation of benzopyrene dihydrodiols with a concomitant decrease in the formation of phenolic metabolites, indicating that benzopyrene undergoes metabolism via arene oxides that are precursors for dihydrodiols and phenols.