New 3-tetrazolyl-ß-carbolines and ß-carboline-3-carboxylates with anti-cancer activity.

The synthesis and in vitro anticancer activity of novel ß-carbolines is reported. New tryptamines have been prepared via hetero-Diels-Alder reaction of nitrosoalkenes with indoles and used to prepare functionalized ß-carbolines by the Pictet-Spengler approach. These included 6-substituted-ß-carboline-3-carboxylates and 3-(1H-tetrazol-5-yl)-ß-carbolines, whose synthesis is reported for the first time. Carboline-3-carboxylates derived from l-tryptophan methyl ester were also prepared. The structural diversity that was achieved allowed the discovery of impressive activities against a range cancer cell lines with the selectivity depending on the type of substitution pattern of the ß-carboline core. We have identified at least one ß-carboline derivative with GI50 ≤ 1  µM for each of the following human tumor cell lines: glioblastoma (U251), melanona (UACC-61), breast (MCF-7), ovarian expressing multiple-drug-resistance phenotype 4 (NCI-ADR/RES), renal (786-0), lung (NCI-H460), ovarian cancer (OVCAR-3), leukemia (K-562) and colon (HT29). These results demonstrated that the new ß-carboline derivatives are very promising anticancer agents.

Synthesis and antiviral activity of beta-carboline derivatives bearing a substituted carbohydrazide at C-3 against poliovirus and herpes simplex virus (HSV-1).

Several novel 1,3-disubstituted beta-carboline derivatives bearing a substituted carbohydrazide group at C-3 were synthesized and evaluated for their antiviral activity against vaccinal poliovirus (VP) and herpes simplex virus type 1 (HSV-1). The cytotoxicity and selectivity index of the active compounds were also evaluated. Among the synthesized derivatives, compounds 10 and 11 displayed potent activity against both vaccinal poliovirus and HSV-1 virus. Compound 10 presented the highest selectivity index (SI=2446.8) against HSV-1 virus and low cytotoxicity (CC(50)=1150.0+/-67.3 microM). The virus yield inhibition assay showed that compound 10 was able to inhibit HSV-1 plaque formation before and during the virus adsorption. The characteristic small plaque pattern observed in compound-treated cells suggested that compound 10 inhibited viral dissemination to neighboring cells. A computational study for prediction of ADME properties of the novel synthesized beta-carbolines derivatives was performed by determination of lipophilicity, topological polar surface area (TPSA), absorption (% ABS) and simple molecular descriptors, using Lipinski's rule.