Ruthenium(II)-Catalyzed Dearomatized C-H Activation and Annulation Reaction of Vinylnaphthols with Alkynes: Access to Spiro-Pentacyclic Naphthalenones.

The ruthenium(II)-catalyzed annulation of vinylnaphthols and alkynes is described. The reaction proceeds through C-H activation, dearomatization, and alkyne insertion. This reaction affords spiro-pentacyclic naphthalenones that have biological significance in good yields.

Ruthenium(II)-Catalyzed Synthesis of Spirobenzofuranones by a Decarbonylative Annulation Reaction.

The first decarbonylative insertion of an alkyne through C-H/C-C activation of six-membered compounds is reported. The Ru-catalyzed reaction of 3-hydroxy-2-phenyl-chromones with alkynes works most efficiently in the presence of the ligand PPh3 to provide spiro-indenebenzofuranones. Unlike previously reported metal-catalyzed decarbonylative annulation reactions, in the present decarbonylative annulation reaction, the annulation occurs before extrusion of carbon monoxide.

Cytotoxic and apoptosis-inducing effects of novel 8-amido isocoumarin derivatives against breast cancer cells.

Isocoumarin is a lactone, a type of natural organic compound that is used as synthetic intermediates of several natural products and pharmaceutical compounds explored for their potential therapeutic applications like antifungal, antimicrobial, anti-inflammatory, and anticancer activities. In our previous work, we were the first group to report the use of amide C-N bond of isatins as the oxidizing directing group for the synthesis of 8-amido isocoumarin derivatives. Whereas in our present work, we have screened the cytotoxic effects of novel 8-amido isocoumarin derivatives (S1-S10) in human breast cancer MCF-7 and MDA-MB-231 cells. Our novel results revealed that N-(3-(4-methoxyphenyl)-1-oxo-4-(4-propylphenyl)-1H-isochromen-8yl)acetamide (S1) and N-(4-(3,5-difluorophenyl)-1-oxo-3-(p-tolyl)-1H-isochromen-8-yl) acetamide (S2) are the two potent compounds among the rest synthesized isocoumarin derivatives that are cytotoxic against MCF-7 and MDA-MB-231 cells, whereas less toxic to the non-tumorigenic IOSE-364 cells. Flow cytometry studies have confirmed the induction of apoptotic effects of compounds by Annexin V/PI double staining. We also observed the cytotoxic effects of S1 and S2, as evaluated by DAPI-PI immunostaining and H&E staining. The morphological alterations consistent with apoptotic blebs were observed in both cancer cells treated with compounds assessed by scanning electron microscopy. Overall, this present study strongly demonstrates that 8-amido isocoumarin derivatives have potent cytotoxic and apoptotic effects in breast cancer cells.

Ru(II)-Catalyzed and Ligand-Controlled C-H Activation and Annulation via 1,2-Phenyl Shift: Synthesis of Quaternary Carbon-Centered Pyrimidoindolones.

A novel Ru(II)-catalyzed C-H activation and annulation reaction of N-arylpyrazol-5-ones and diaryl/arylalkyl-substituted alkynes is developed. Unlike the reported metal-catalyzed C-H activation and annulation reactions, in the present bidentate amine-ligand controlled C-H activation and annulation reaction, the annulation occurs via a 1,2-aryl shift to afford quaternary carbon-centered pyrimidoindolones.