Synthesis of 2-Mercapto-(2-Oxoindolin-3-Ylidene)Acetonitriles from 3-(4-Chloro-5H-1,2,3-Dithiazol-5-Ylidene)Indolin-2-ones

Alkylidene oxindoles are important functional moieties and building blocks in pharmaceutical and synthetic chemistry. Our interest in biologically active compounds focused our studies on the synthesis of novel oxindoles, bearing on the exocyclic double bond at the C8, CN, and S groups. Extending the potential applications of Appel’s salt, we developed a new synthetic approach by investigating the reactions of C5-substituted 2-oxindoles with 4,5-dichloro-1,2,3-dithiazolium chloride (Appel’s salt) to give original (Z)-3-(4-chloro-5H-1,2,3-dithiazol-5-ylidene)indolin-2-one derivatives, and new 2-mercapto-(2-oxoindolin-3-ylidene)acetonitriles via a dithiazole ring-opening reaction. The work described in this article represents further applications of Appel’s salt in the conception of novel heterocyclic rings, in an effort to access original bioactive compounds. Fifteen new compounds were prepared and fully characterized.

Microwave-assisted kinetic resolution of homochiral (Z)-cyclooct-5-ene-1,2-diol and (Z)-2-acetoxycyclooct-4-enyl acetate using lipases

Over the last decade, the use of biocatalysts has become an attractive alternative to conventional chemical methods, especially for organic synthesis, due to their unusual properties. Among these enzymes, lipases are the most widely used, because they are cheap, easily available, cofactor-free, and have broad substrate specificity. Combined to microwave heating in non-aqueous medium, recent results suggest that irradiation may influence the enzyme activity. This Communication reports the benefits of lipases and the microwave irradiation on the kinetic resolution of racemic homochiral (Z)-cyclooct-5-ene-1,2-diol and (Z)-2-acetoxycyclooct-4-enyl acetate. In order to best achieve the kinetic resolution, different parameters were studied including the type of lipase, the temperature, the impact of microwave power compared to conventional heating. Optimization of the reaction parameters lead to the obtainment of highly enriched or enantiopure diols and diesters in a clean, efficient and safe way.

Synthesis and antitumoral activity of novel thiazolobenzotriazole, thiazoloindolo[3,2-c]quinoline and quinolinoquinoline derivatives

The biological evaluation of some novel thiazoloindolo[3,2-c]quinoline, 8-substituted-11H-indolo[3,2-c]quinolines is described. These compounds were obtained via Graebe-Ullmann thermal cyclization from appropriated N-arylated benzotriazoles. 7H-4,7-Diaza-benzo[de]anthracene, a reaction by-product structurally closed to the pyridoacridine skeleton was also identified. All thiazolobenzotriazole intermediates were tested in vitro for their capacity to inhibit the growth of two breast cancer cell lines, MCF-7 and MDA-MB-231. In parallel, the newly synthesized skeletons were evaluated for DNA interaction, topoisomerases' inhibition, and cytotoxicity against HL60 and HL60/MX2 human leukemia cells. Most compounds showed a potent growth inhibitory effect on all the tested cell lines, with IC(50) in the muM range.

Microwave-assisted Synthesis of Novel Thiazolocarbazoles and Evaluation as Potential Anticancer Agents. Part III

Novel 6-substituted thiazolocarbazole derivatives have been synthesized under microwave irradiation via the corresponding imino-1,2,3-dithiazoles. In vitro antitumor potential of these polyheterocyclic compounds was evaluated. Among all the tested thiazolocarbazoles, compound 10 is the most effective in inhibiting cell growth.

Microwaves in drug discovery and multi-step synthesis

The interest of microwaves in drug discovery and multi-step synthesis is exposed with the aim of describing our strategy. These studies are connected with our work on the synthesis of original heterocyclic compounds with potential pharmaceutical value. Reactions in the presence of solvent and solvent-free synthesis can be realised under a variety of conditions; for some of these selected results are given, and where available, results from comparison with the same solvent-free conditions but with classical heating are given.