Synthesis and antiinflammatory activity of some 2-substituted 4- and 7-benzoxazoleacetic and alpha-methylacetic acids

4- and 7-benzoxazoleacetic and alpha-methylacetic acids substituted in the 2 position with phenyl and substituted phenyl groups have been synthesized and tested on the carrageenan-induced rat paw edema assay. The only compound found to have significant activity, albeit of a low order, was 2-phenyl-alpha-methyl-7-benzoxazoleacetic acid.

Synthesis of substituted thiobenzoxazoles/benzothiazoles: inhibition of cellular respiratory and monoamine oxidase activities and anticonvulsant property

Several 2-(substituted alkoxy/hydrazinocarbonyl acetanilidothio)benzoxazoles/benzothiazoles were synthesized and characterized by their sharp melting points, elemental analyses, and IR spectra. All thiobenzoxazoles/benzothiazoles possessed low anticonvulsant activity, which was reflected by the 10-40% protection afforded by these compounds against pentylenetetrazol-induced convulsions. All thiobenzoxazoles/benzothiazoles inhibited selectively the nicotinamide adenine dinucleotide (NAD)-dependent oxidation of pyruvate, DL-isocitrate, and alpha-ketoglutarate by rat brain homogenates. NAD-independent oxidation of succinate remained unaltered. All 2-(substituted hydrazinocarbonyl acetanilidothio)benzoxazoles/benzothiazoles inhibited monoamine oxidase activity of rat brain homogenates. Greater monoamine oxidase inhibition was observed with thiobenzothiazoles than with the corresponding thiobenzoxazoles/benzothiazoles was found to be unrelated with their ability to inhibit cellular respiratory and monoamine oxidase activities of rat brain homogenates.

Effects of 4-nitrobenzofurazans and their N-oxides on synthesis of protein and nucleic acid by murine leukemia cells

A series of benzo-2,1,3-oxadiazoles (benzofurazans) and their N-oxides (benzofuroxans) inhibit incorporation of precursors into nucleic acids and protein by murine leukemia cells. At slighly higher levels, substantial single- and double-strand DNA breakage was observed. At still higher concentrations, inhibition of phosphorylation of uridine and thymidine was found. Structure-activity relationships show that only compounds bearing appropriate substitutions at positions 4 and 7 were effective inhibitors of biosynthetic pathways. Such compounds appear to interact with a wide variety of biological systems and may be useful in elucidating modes of macromolecule synthesis.

Effects of some antitumor agents on growth and glycolytic enzymes of the flagellate Crithidia

Some antitumor agents known to specifically inhibit certain tumor cell enzymes were examined for activity against glycolytic enzymes and growth of the insect trypanosomatid, Crithidia fasciculata. The cytoplasmic enzymes hexokinase, alpha-glycerophosphate dehydrogenase, malic dehydrogenase, and glucose-6-phosphate dehydrogenase were tested. Agaricic acid (2-hydroxy-1,2,3-nonadecane tricarboxylic acid) was highly inhibitory (50 to 100%) to malic and alpha-glycerophosphate dehydrogenases at approximately 3 x 10(-5)m; 2-(p-hydroxyphenyl)-2-phenylpropane (2 x 10(-4)m), and 5,6-dichloro-2-benzoxazolinone (5 x 10(-4)m) were less effective (50% inhibition) against them. The antiprotozoal agents primaquine (4 x 10(-4)m) and Melarsoprol (8 x 10(-4)m) were 30 to 40% inhibitory. Agaricic acid, 2-(p-hydroxyphenyl)-2-phenylpropane, and 5,6-dichloro-2-benzoxazolinone inhibited growth of Crithidia at less than 10(-4)m. Eight other test compounds from the Cancer Chemotherapy National Service Center (CCNSC) were not toxic to cell growth, although two (4-biphenylcarboxylic acid and 1-[p-chlorobenzyl]-2-ethyl-5-methyl-indole-3-acetic acid) inhibited Crithidia alpha-glycerophosphate dehydrogenase below 1 mm. All of the compounds used specifically inhibited cancer cell alpha-glycerophosphate dehydrogenase. The corresponding enzyme in pathogenic African trypanosomes is important in their terminal respiration. C. fasciculata may be useful in preliminary evaluation of chemotherapeutic agents as potential trypanocides.