in this report, synthesis, characterization and application of silica perchloric acid nanosphere as a novel and heterogeneous catalyst is described. these nanospheres have been characterized by xrd, ft-ir, bet and tga spectra and also by sem and tem images. the results show that it has a spherical shape and the particles size are between 75 and 100 nm. the catalytic activity has been investigat...

This article describe the applicability of 1,4-disulfopiperazine-1,4-diium chloride ([Piper-(SO3H)2].2Cl) as a green, versatile and Brönsted acidic ionic catalyst in the promotion of the synthesis of phthalazine derivatives via one-pot three component reaction between aromatic aldehydes, 1,3-diketone derivatives and phthalhydrazide under solvent-free reaction cond...

Hepatitis A virus (HAV) 3C enzyme is a picornaviral cysteine proteinase involved in the processing of the initially synthesized viral polyprotein and is therefore important for viral maturation and infectivity. Although it is a cysteine proteinase, this enzyme has a topology similar to those of the chymotrypsin-like serine proteinases. Since the enzyme recognizes peptide substrates with a gluta...

Sulfonated magnetic nanoparticles (SO3H-Fe3O4@SiO2 MNPs) have been explored as an efficient, cost-effective, and recyclable nanocatalyst for the facile synthesis of 3,4-dihydro-2H-indazolo[1,2-b]phthalazin-1,6,11(13H)-triones through a one-pot three-component reaction between aldehydes, dimedone, and phthalhydrazide under mild and green (solvent-f...