Biomedical subjects
Publications and source records attributed to R Calvino.
Synthesis, antibacterial activity and stability in acid solution of potassium salts of 6-(3-methyl-4-furoxancarboxyamido)penicillanic acid and 6-(4-methyl-3-furoxancarboxyamido)penicillanic acid are reported.
A new class of methylfuroxans and methylfurazans arylthio, arylsulphinyl and arylsulphonyl substituted, characterized by vasodilating and antiaggregatory properties, is described. Vasodilating activity, tested on rabbit aortic rings percontracted with 1 microM noradrenaline, is enhanced by N-oxidation of the furazan ring and is maximized by increase of the sulphur atom oxidation level. Compounds 4-methyl-3-(p-methoxyphenylsulphonyl) furoxan 6c, 3-phenyl-4-phenylsulphonylfuroxan 10, 4-phenyl-3-phenylsulphonylfuroxan 11 and 3,4-bis(phenyl-sulphonyl)furoxan 12 (EC50 values ranging between 0.055-1.07 microM), seem to be promising since they show the highest potency as well as maximal efficacy, causing complete reversal of noradrenaline induced contraction. The structure-activity relationship, observed in the platelet aggregation test, is substantially similar to that reported for the vasodilating activity, in line with the general profile of these drugs as putative NO-mimetic derivatives.
Synthesis of aryl and heteroarylazocyanides, azoxyesters and azoxysulphones, was carried out by the action of appropriate reagents on the corresponding nitroso derivatives and arylazoxyamides were obtained by hydrolysis of the corresponding azoxycyanides. Cytotoxic activity was assessed utilizing cultured P388 leukemia cells. Most of the compounds tested showed a marked cytotoxicity at concentrations below 1 micrograms/ml.