Antitrypanosomal and antileishmanial activities of novel N-alkyl-(1-phenylsubstituted-beta-carboline)-3-carboxamides.

A series of 1-phenylsubstituted beta-carbolines containing an N-butylcarboxamide group at C-3 of beta-carboline nucleus were synthesized and evaluated in vitro against epimastigote form of Trypanosoma cruzi and promastigote form of Leishmania amazonensis. Among all compounds tested, two derivatives (2b and 2d) presented potent activity against both parasites. The most active derivative 2b showed also the higher selectivity index ratio (SI) for L. amazonensis (SI=2,084). The effect of other N-alkylcarboxamide groups at C-3, such as pyrrolidyl, N-cyclohexil and N-benzylcarboxamide on T. cruzi and L. amazonensis activity was also evaluated. Our results pointed the synthesized beta-carboline-3-carboxamide derivatives as potential compounds for new drugs for Chagas' disease and leishmaniasis' treatment.

Comparative study of the trypanocidal activity of the methyl 1-nitrophenyl-1,2,3,4-9H-tetrahydro-beta-carboline-3-carboxylate derivatives and benznidazole using theoretical calculations and cyclic voltammetry.

The cis and trans isomers of methyl 1-(m-nitro)phenyl and 1-(p-nitro)phenyl-1,2,3,4-tetrahydro-9H-beta-carboline-3-carboxylates (compounds 3a,b, 4a and b) were synthesized and evaluated in vitro against epimastigote forms of Trypanosoma cruzi. Among all of the evaluated tetrahydro-beta-carboline derivatives, the compound trans-methyl 1-(m-nitro)phenyl-1,2,3,4-9H-tetrahydro-beta-carboline-3-carboxylate (3b) was found to exhibit significant trypanocidal activity (IC(50)=22.2 microM). Theoretical studies of molecular conformations and electronic properties for the synthesized compounds and benznidazole, as well as, the cyclic voltammetric (CV) behaviors' determination were performed. A comparative study of the trypanocidal activity of the nitrophenyl-tetrahydro-beta-carbolines derivatives and benznidazole, using the results of theoretical calculations and of the cyclic voltammetry experiments, is presented.

Synthesis and antitumoral activity of novel 3-(2-substituted-1,3,4-oxadiazol-5-yl) and 3-(5-substituted-1,2,4-triazol-3-yl) beta-carboline derivatives.

Several novel 1-substituted-phenyl beta-carbolines bearing the 2-substituted-1,3,4-oxadiazol-5-yl and 5-substituted-1,2,4-triazol-3-yl groups at C-3 were synthesized and evaluated for their in vitro anticancer activity. The assay results pointed thirteen compounds with growth inhibition effect (GI(50)<100 microM) for all eight different types of human cancer cell lines tested. The beta-carbolines 7a and 7h, bearing the 3-(2-metylthio-1,3,4-oxadiazol-5-yl) group, displayed high selectivity and potent anticancer activity against ovarian cell line with GI(50) values lying in the nanomolar concentration range (GI(50)=10 nM for both compounds). The 1-(N,N-dimethylaminophenyl)-3-(5-thioxo-1,2,4-triazol-3-yl) beta-carboline (8g) was the most active compound, showing particular effectiveness on lung (GI(50)=0.06 microM), ovarian and renal cell lines. The potent anticancer activity presented for synthesized compounds 7a, 7h, and 8g, together with their easiness of synthesis, makes these compounds promising anticancer agents.