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The surface of SBA-15 was functionalized using diphenylphosphine and then it was treated with butane sultone and sulfuric acid to obtain Brønsted acid HO3S-phosphonium based ionic liquid functionalized SBA-15 with 4-methylbenzenesulfonate (p-TS–) as a counteranion. [HO3S-PhospIL@SBA-15], efficiently catalyzed synthesis of 2-amino-3-cyano-4,6-diarylpyridine derivatives through the reaction of chalcones, malononitrile, and ammonium acetate in good yields at 50°C in EtOH. [ABSTRACT FROM PUBLISHER]

Modified β-casein (mβ- CN) was investigated as an efficient additive for thermal reversibility of human carbonic anhydrase II ( HCA II) at p H 7.75. The mβ- CN was obtained via modification of β-casein (β- CN) acidic residues using Woodward's reagent K. The effects of mβ- CN on the reversibility and stability of HCA II were determined by differential scanning calorimetry, UV-vis, and 1-anilinonaphthalene-8-sulfonic acid fluorescence spectroscopic methods. The mβ- CN, as an additive, enhanced thermal reversibility of HCA II by 33%. Together, our results indicated that mβ- CN is very efficient in decreasing thermal aggregation and enhancing the stability of HCA II. Using theoretical studies, we propose that the mechanism for thermal reversibility is mediated through formation of a salt bridge between the Woodward part of mβ- CN and the Zn ion of HCA II. [ABSTRACT FROM AUTHOR]

Abstract: A highly efficient and green system is introduced to chemical synthesis. Magnetic nanoparticle-supported propylsulfamic acid deposited onto hydroxyapatite [γ-Fe2O3-HAp-(CH2)3-NHSO3H] synthesized as a unique heterogeneous acid catalyst of excellent activity and recyclable for at least 10 reaction runs without significant loss of activity. The facile recovery of the catalyst is carried out by applying an external magnet device. It is both “green” and efficient. The catalyst was fully characterized by spectroscopic, magnetic, adsorptive and thermal techniques (TEM, SEM, FTIR, TGA, XRD, BET, elemental analysis (CHNOS) and VSM). [ABSTRACT FROM AUTHOR]

Abstract: Treatment of aqueous formic acid (85%) with structurally diverse amines in the presence of a catalytic amount of sulfonic acid supported on hydroxyapatite-encapsulated-γ-Fe2O3 [HAp@-γ-Fe2O3] (0.9mol.%) as a heterogeneous, reusable and highly efficient catalyst gave the corresponding formamides in good to excellent yields at room temperature. The magnetically catalytic system was recovered by-passing time consuming filtration operation by using an external magnet device. In addition to facility, this methodology, it also enhances product purity and promises economic as well as environmental benefits. [Copyright &y& Elsevier]

A variety of monospiro-2-aminopyran derivatives such as (IV), (VII), and (X) (24 examples) are synthesized via three-component coupling of isatin (I) or ninhydrin (VIII) with malononitrile (II) and 1,3-dicarbonyl compounds. [ABSTRACT FROM AUTHOR]