Showing papers by "Giuseppe Paglietti published in 1997"

Quinoxaline chemistry. Part 7. 2-[aminobenzoates]- and 2-[aminobenzoylglutamate]-quinoxalines as classical antifolate agents. Synthesis and evaluation of in vitro anticancer, anti-HIV and antifungal activity.

Abstract: Thirty-three quinoxalines bearing an aminobenzoyl or aminobenzoylglutamate group on position 2 and various substituents on position 3,6,7 of the heterocycle were prepared in order to evaluate in vitro anticancer activity. Preliminary screening performed at NCI showed that most derivatives exhibited a moderate to strong growth inhibition activity on various tumor panel cell lines between 10(-5) and 10(-4) Molar concentrations. Interesting selectivities were also recorded between 10(-8) and 10(-6) M. Among the series examined one compound (29) which was the most active also exhibited both in vitro anti-HIV protection and antifungal activity while in other two (31, 37) the antifungal activity was prevailing.

Quinoxaline chemistry. Part 8. 2-[Anilino]-3-[carboxy]-6(7)-substituted quinoxalines as non classical antifolate agents. Synthesis and evaluation of in vitro anticancer, anti-HIV and antifungal activity.

Abstract: Thirty quinoxalines bearing a substituted anilino group on position 2, a carboethoxy or carboxy group on position 3 and a trifluoromethyl group on position 6 or 7 of the heterocycle were prepared in order to evaluate in vitro anticancer activity. Preliminary screening performed at NCI showed that most derivatives exhibited a moderate to strong growth inhibition activity on various tumor panel cell lines between 10(-5) and 10(-4) molar concentrations. Interesting selectivities were also recorded between 10(-8) and 10(-6) M for a few compounds. One single compound exhibited good activity against Candida albicans.

Quinoxaline Chemistry. Part 6. Synthesis and Evaluation of Antiulcer and Gastroprotective Activity of 2‐(Arylmethylmercapto‐, Arylmethylsulfinyl‐, Piperazinyl‐3‐R‐substituted) Quinoxalines.

Abstract: Thirty compounds possessing quinoxaline structure bearing either substituted arylmethylmercapto-, arylmethylsulfinyl group or a piperazinyl moiety in position 2 were prepared in order to evaluate an antiulcer and gastroprotective activity in rat pylorus ligature, in comparison with omeprazole and ranitidine at the dose of 100 mg/kg after oral administration. Among the compounds of the first group one third showed a moderate activity being about half potent as omeprazole whereas in the second group compound 5b exibited an activity superior to that of ranitidine accompanied with the lowest incidence of lesions and mortality and another compound (5i) was equiactive as ranitidine.

Reactions of Benzotriazoles with Diethyl Ethoxymethylenemalonate; Ethylation and Michael Addition. Comparison with Other Esters and N‐ Heterocycles.

Abstract: Benzotriazole and its 5-methyl-and 5-nitro derivatives react with diethyl ethoxymethylenemalonate by ethylation at each of the ring N-atoms and through Michael addition, to give the isomeric esters ethyl (E/Z) 3-[5(6)-R-benzotriazol-1-yl]propenoates. Benzotriazole and its 5-nitro derivative react similarly with ethyl acetoacetate but N-ethyl derivatives are obtained in lower yields. Other 1,2,3-triazoles derivatives and indole were ineffective in this reaction while benzimidazole produced similar results but accompanied with a small amount of a benzimidazoline addition product, whose structure has been determined by crystallo-graphic analysis.