Heterogeneous catalyst SiO-LaCl·7HO: characterization and microwave-assisted green synthesis of α-aminophosphonates and their antimicrobial activity.

Silica-supported lanthanum (III) chloride (SiO-LaCl·7HO) was prepared and characterized by infrared spectroscopy, X-ray diffraction analysis, scanning electron microscope, energy-dispersive X-ray spectroscopy, thermogravimetric analysis and differential thermal analysis techniques. The catalytic activity of this silica-supported lanthanum (III) chloride was investigated in a one-pot three-component Kabachnik-Fields reaction. A library of new α-aminophosphonates was prepared employing various benzothiazole and thiadiazole amines, different substituted aldehydes and diethylphosphite under solvent-free conditions using conventional/microwave methods with good to excellent yields (85-97%).

and antioxidant activity profiles of urea and thiourea derivatives of 5-hydroxytryptophan.

A series of new urea and thiourea derivatives of 5-hydroxy tryptophan was designed and synthesized from 5-hydroxy tryptophan () by treating various isocyanates and isothiocyanates in the presence of triethylamine (TEA) as a base. The antioxidant activities of the newly synthesized compounds were evaluated by using different assays such as 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide (HO) and superoxide. The results obtained from the studies revealed that the compounds , , , and exhibited the significant high content of antioxidant activity.