A Palladium-Catalyzed Carbonylation Approach to Eight-Membered Lactam Derivatives with Antitumor Activity.

The reactivity of 2-(2-alkynylphenoxy)anilines under PdI2 /KI-catalyzed oxidative carbonylation conditions has been studied. Although a different reaction pathway could have been operating, N-palladation followed by CO insertion was the favored pathway with all substrates tested, including those containing an internal or terminal triple bond. This led to the formation of a carbamoylpalladium species, the fate of which, as predicted by theoretical calculations, strongly depended on the nature of the substituent on the triple bond.

Diversity-oriented synthesis of α-aminophosphonates: a new class of potential anticancer agents.

A small library of structurally diverse α-aminophosphonates has been synthesized by reacting alkyl/aryl aldehydes, alkyl/aryl amines and alkyl/aryl phosphites in one-pot catalyzed by Amberlite-IR 120 resin (acidic). All the synthesized α-aminophosphonates were assayed for their in vitro cytotoxic activities against a panel of five human cancer cell lines including A-549, NCI-H23 (Lung), Colo 320DM (Colon), MG-63 (Bone marrow) and Jurkat (Blood T lymphocytes). Compound 4n having (R)-1-phenylethanamine was found to be the most active amongst all the synthesized α-aminophosphonates against all the five cancer cell lines, most prominent being against Jurkat cell line with an IC50 value of 4 μM.

An efficient synthesis of benzodiazepinyl phosphonates as clostripain inhibitors via FeCl3 catalyzed four-component reaction.

A novel one-pot route for the synthesis of benzodiazepinyl phosphonates (BDPs) has been achieved. FeCl(3) efficiently catalyzed four-component condensation of diamines, acetone and phosphites in the presence of molecular sieves to furnish BDPs as novel chemical entities with good yield. The synthesized BDPs have shown significant protease inhibition activity against clostripain, a disease model for gas gangrene, suggesting that these novel chemical entities could be further explored as cysteine protease inhibitors.

Ionic liquid promoted synthesis, antibacterial and in vitro antiproliferative activity of novel α-aminophosphonate derivatives.

Ionic liquid ethyl ammonium nitrate is used as an excellent catalyst and solvent for three-component one-pot reaction of an aldehydes, amines and diethylphosphite to form novel α-aminophosphonates at room temperature. Among the various catalysts, the preparation of ethyl ammonium nitrate is an environmental friendly, cost effective and recyclable catalyst. Compounds 4b, 4c, 4d, 4f and 4j were found more potent antibacterials against pathogenic microorganisms.