Synthesis and Characterization of Metabolites and Potential Impurities of the Antiulcerative Drug Tenatoprazole

Tenatoprazole (Ulsacare^®) is a recently developed antiulcerative drug used for the treatment of both erosive and nonerosive gastroesophageal reflux disease. During the bulk synthesis of tenatoprazole, we have observed four impurities (tenatoprazole N‐oxide, tenatoprazole sulfone N‐oxide, N‐methyl tenatoprazole, and desmethoxy tenatoprazole) and two metabolites (tenatoprazole sulfide and tenatoprazole sulfone). The present work describes the synthesis and characterization of these impurities.     

ZrOCl2·8H2O: An Efficient Catalyst for One-Pot Synthesis of α-Amino Phosphonates Under Solvent-Free Conditions

A highly efficient protocol has been developed for the three-component reaction of an amine, an aldehyde, and diethyl phopshite catalyzed by ZrOCl₂·8H₂O, an environmentally friendly catalyst, at ambient temperature. The catalyst exhibited remarkable activity and tolerated a wide variety of functional groups, providing the desired amino phosphonates in excellent yields under solvent-free conditions. Alternatively, the reaction rate can be significantly enhanced by carrying out the reaction in a monomode microwave reactor as a promoter.     

Biochemical and Kinetic Study of Laccase from Ganoderma cupreum AG-1 in Hydrogels

In the present study, three different types of hydrogels i.e., (poly (?acrylamide)/alginate (P (AAm)/Alg), poly (acrylamide-N-isopropylacrylamide) (P (AAm-NIPA)), and poly (acrylamide-N-isopropylacrylamide)/alginate (P (AAm-NIPA)/Alg)) were synthesized by acrylamide, alginate, and N-isopropylacrylamide for the entrapment of laccase. The hydrogel-entrapped and free laccase showed optimum temperature of 50 °C for the oxidation of ABTS, but the entrapped laccase showed high temperature, pH, and storage stability as compared to the free enzyme. The K _m values of free laccase, (P (AAm)/Alg)-L, (P (AAm-NIPA))-L, and (P (AAm-NIPA)/Alg)-L were found to be 0.13, 0.28, 0.33, and 0.50 mM, respectively. The V _max values of free laccase, (P (AAm)/Alg)-L, (P (AAm-NIPA))-L, and (P (AAm-NIPA)/Alg)-L were found to be 22.22?×?10², 5.55?×?10², 5.0?×?10², and 4.54?×?10² mM/min, respectively. The entrapped laccase hydrogels were used for the decolorization of Reactive Violet 1 dye, with 39 to 45 % decolorization efficiency till the 10th cycle.     

A short and efficient synthesis of furo[2,3-b]indoles

Application of Wittig olefination-Claisen rearrangement protocol for the short synthesis of furo[2,3-b]indoles is described.     

A Facile Diversity‐Oriented Multicomponent One‐Pot Synthesis of 3‐Amino‐6,7‐dihydrobenzo[c]thiophen‐4(5H)‐one Derivatives from α‐Oxo‐N,S‐ketene Acetal

A convenient one‐pot multicomponent method for the preparation of 3‐amino‐6,7‐dihydrobenzo[c]thiophen‐4(5H)‐one derivative has been developed. Reaction of 1,3‐cyclohexanedione and phenyl isothiocynate gave α‐oxo‐N,S‐ketene acetal that were reacted in situ with 2‐chloromethylquniazoline‐4‐one derivatives, in the presence of sodium hydride to afford the target compound in reasonable overall yields.     

Latex-mediated synthesis of ZnS nanoparticles: green synthesis approach

A low-cost, green synthesis of ZnS nanoparticles is reported using 0.3 % latex solution prepared from Jatropha curcas L. ZnS nanoparticles were characterized by X-ray diffraction, selected area electron diffraction, transmission electron microscopy, energy dispersive analysis of X-rays, UV–vis optical absorption and photoluminescence techniques. Fourier Transform Infrared Spectroscopy was performed to find the role of cyclic peptides namely curcacycline A (an octapeptide), curcacycline B (a nonapeptide) and curcain (an enzyme) as a possible reducing and stabilizing agents present in the latex of J. curcas L. The average size of ZnS nanoparticles was found to be 10 nm. Latex of J. curcas L. itself acts as a source of sulphide (S⁻²) ions that are donated to Zn ions under present experimental conditions. Source of sulphide (S⁻²) ions is still unclear, but we speculate that cysteine or thiol residues present in enzyme curcain may be donating these sulphide (S⁻²) ions.     

Acoustical Studies of Schiff Bases in 1,4-dioxane and Dimethylformamide at 308.15K

Variousworkershavereportedthepreparation,chemicalandphysicalpropertiesofvariousSchiffbases犤1-5犦.Schiffbasesareknowntobeimportantduetotheirapplicationsintheprepa-rationofdyes,liquidcrystalsandpowerfulcorrosionin-hibitors.Furthermore,theyareusedinthemecha…