title: Silica-supported fluoroboric acid (HBF(4)-SiO(2)) catalyzed highly productive synthesis of thiomorpholides as activators of l-asparaginase as well as the antioxidant agent.
abstract: An efficient solvent-free procedure for the synthesis of thiomorpholides in the presence of a catalytic amount of solid-supported fluoroboric acid (HBF(4)-SiO(2)) is described. The advantages of this method are high yields, short reaction times, ease of product isolation, low cost, and the catalyst can be recycled for a number of times without significant loss of activity. Three thiomorpholides possessing electron-donating group (4c, 4g, and 4h) were exhibiting excellent stimulatory activities against Erwinia carotovoral-asparaginase. The most potent activator, compound 4h displayed the following kinetic parameters, K(m)=75microM and V(max)=1000micromolmg(-1)min(-1) and K(A)=0.985microM. Furthermore, these compounds (4g, 4h, 4c, 4f, 4a, and 4d) have also shown promising 2,2'-diphenyl-1-picrylhydrazyl (DPPH) reducing antioxidant activity (21-36%) at 1mM concentration as compared to standard butylated hydroxyl anisole (72% at 1mM).
authors.affiliation: Medicinal Chemistry Research Laboratory, School of Chemical Sciences, Solapur University, Solapur 413 255, India. bandgar_bp@yahoo.com
authors.forename: Babasaheb P
authors.initials: BP
authors.lastname: Bandgar
authors.forename: Shrikant S
authors.initials: SS
authors.lastname: Gawande
authors.forename: Suchita C
authors.initials: SC
authors.lastname: Warangkar
authors.forename: Jalinder V
authors.initials: JV
authors.lastname: Totre
mesh_terms: D000975:Antioxidants / Q000138:chemical synthesis* / Q000494:pharmacology; D001215:Asparaginase / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism; D001713:Biphenyl Compounds / Q000138:chemical synthesis* / Q000494:pharmacology*; D001881:Borates / Q000737:chemistry*; D002384:Catalysis; D020536:Enzyme Activators / Q000138:chemical synthesis / Q000494:pharmacology; D004885:Erwinia / Q000201:enzymology; D009025:Morpholines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D010851:Picrates / Q000138:chemical synthesis* / Q000494:pharmacology*; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D001426:Bacterial Proteins; D001713:Biphenyl Compounds; D001881:Borates; D020536:Enzyme Activators; D009025:Morpholines; D010851:Picrates; C028971:thiamorpholine; D012822:Silicon Dioxide; C004931:1,1-diphenyl-2-picrylhydrazyl; D001215:Asparaginase; C098759:fluoroboric acid