Ketene dithioacetals‐source for different heterocycles

Some pyrazoline, isoxazoline and pyrimidine derivatives were synthesized from ketene dithioacetals using appropriate nucleophiles.     

Pyridazine and phthalazine derivatives with potential antimicrobial activity

Fifteen new pyridazine and phthalazine derivatives were prepared (in good to excellent yields) and tested in vitro as antimicrobial compounds. All the compounds have proved to have a remarkable activity against Gram positive germs, the results on Sarciria Luteea being spectacular. Correlation structure ‐ biological activity have been done. Stereo‐ and region‐ chemistry involved in these reactions are discussed.     

Regioselective synthesis of polyheterocyclic scaffolds by sequential [3,3] sigmatropic rearrangements and pyridine hydrotribromide mediated heterocyclization

A number of tetracyclic polyhetero scaffolds have been regioselectively synthesised in 70‐75% yield from 4‐[(3‐aryloxy‐2‐propynyl)oxy]‐6‐methyl‐pyran‐2‐ones via thionation of the lactone carbonyl, sequential Claisen rearrangements and pyridine hydrotribromide mediated heterocyclization.     

Polystyrene‐supported AICI3: A highly active and reusable heterogeneous catalyst for the one‐pot synthesis of dihydropyrimidinones

An environmentally benign Biginelli protocol for the one‐pot synthesis of substituted 3,4‐dihydropyrimidin‐2(1H)‐ones using polystyrene supported aluminium chloride as catalyst has been achieved. This polymeric catalyst is stable and can be easily recovered and reused without obvious change in their efficiency.