Synthesis and biological evaluation of N-antipyrine-4-substituted amino-3-chloromaleimide derivatives.

This paper describes the synthesis of new cyclic imides obtained by reaction with N-antipyrine-3,4-dichloromaleimides and different aromatic amines. The analgesic activity of the synthesized compounds was initially investigated against the writhing test in mice, followed by analysis of the most promising compounds in this model and in the formalin-induced model. The results indicate that the compounds containing the electron-withdrawing substituents in the para position of the substitute ring exerted more potent analgesic activity in mice, being much more potent than the prototype N-antipyrine-3,4-dichloromaleimide and some reference drugs. Some compounds exhibited activity against human opportunistic and pathogenic fungi, with MIC values of between 40 and 100 µg/mL (91.74 and 236.96 µM), and it was verified that only a few compounds presented potential for cytotoxic activity.

Evaluation of antifungal activity of Piper solmsianum C. DC. var. solmsianum (Piperaceae).

We have studied the crude methanolic extract (CME), some fractions (hexane, dichloromethane and ethyl acetate) and four pure compounds: eupomatenoid-3 (1), eupomatenoid-5 (2), conocarpan (3) and orientin (4), from Piper solmsianum, for possible antifungal activity against 12 pathogenic fungi. The minimal inhibitory concentration (MIC) was determined and the experiments showed that the CME exhibited antifungal action against all the dermatophytes tested, with MIC values of between 20 microg/ml to 60 microg/ml. Similar activity also was verified for the hexane, dichloromethane and ethyl acetate fractions. However, the starting material (CME), and all the fractions, did not exert inhibitory effect against hyaline hyphomycetes and were only discretely active against the zigomycetes and yeasts. Compounds 2, 3 and 4 also exhibited pronounced activity against all the dermatophytes tested (MIC< or =1 to 9 microg/ml) with potency as high as the standard antifungal drug (ketoconazole). Compound 3 also exhibited activity against all the yeasts tested. In conclusion, the antifungal activity of P. solmsianum seems to be related mainly to the presence of compounds 2, 3 (neolignans) and 4 (flavonoid), however it was verified that another active compound, as yet unidentified, exists in the plant.