Fluorescent dyes emitting red light are frequently used in conventional and super-resolution microscopy of biological samples, although the variety of the useful dyes is limited. We describe the synthesis of rhodamine-based fluorescent dyes with absorption and emission maxima in the range of 621-637 and 644-660 nm, respectively and demonstrate their high performance in confocal and stimulated e...

A new polymer acid catalyst, sulfonated hyperbranched poly(arylene oxindole), 5-OH-SHPAO, was prepared for selective cellulose hydrolysis. Its superior catalysis, showing high glucose selectivity at almost full cellulose conversion, is attributed to the presence of an hydroxyl group next to the sulfonic acid, therefore mimicking the separate acid-base pair in the cellulase active site.

the complexation of alkali metal cations by the water-soluble p-sulfonic acid calix(4)arenewas thermodynamically characterized using spectrophotometeric data which are consistentwith the formation of a 1:1 complex resulting from electrostatic interactions between thesulfonato groups and alkali metal cations. in this study, we determined the formationconstants (log k) of the complexes and have c...

easily synthesized1-methyl-3-(2-oxyethyl)-1h-imidazol-3-ium-borate sulfonic acid {[moei]-bsa} as a novel catalyst efficiently promoted the synthesis of quinoxaline derivatives via condensation of various diamines with 1,2-dicarbonyl compounds at room temperature conditions in ethanol. this research provides a new method for the synthesis of quinoxalines in good to excellent yields with little c...

The present investigation deals with synthesis of new acid dyes from 4-amino-1-(4-sulfophenyl)-3-methyl-5-pyrazolone and phenol derivatives and their metal complexes (Cu (II) and Fe (II)). The phenol derivatives include 4-chlorophenol, 4-nitrophenol, 4-hydroxybenzene sulfonic acid, 2-nitrophenol-4-sulfonic acid, resorcinol and bisphenol A and bisphenol S. The newly synthesized dyes were applied...

A propanetricarboxylic acid ornamented multi-CeIII encapsulated phospho(III)tungstate [H2N(CH3)2]4Na4H2[Ce4(HP)W4(H2O)14(H2PTCA)2O18][(HPIII)2W22O76]·16H2O (1, H3PTCA = 1,2,3-propanetricarboxylic acid) was obtained by a facile one-step reaction of Na2WO4·2H2O, H3PO3, Ce(NO3)·6H2O, itaconic (H2ICA) and dimethylamine hydrochloride. Notably, the polyanion 1 possesses neotype [(HPIII)2W22O76]12‒ fr...

one-pot multicomponent reaction between isatin, barbituric acid, and 6-amino-1,3-dimethyl uracil was investigated in the presence of sulfonic acid functionalized nanoporous silica (sba-pr-so3h) and resulted in the formation of spirooxindole dipyrimidines. spirooxindole unit is found in many natural products and biologically active molecules and 1,4-dihydropyridines are an important class of com...

A systematic study of acid organocatalysts for the polyaddition of poly(ethylene glycol) to hexamethylene diisocyanate in solution has been performed. Among organic acids evaluated, sulfonic acids were found the most effective for urethane formations even when compared with conventional tin-based catalysts (dibutyltin dilaurate) or 1,8-diazabicyclo[5.4.0]undec-7-ene. In comparison, phosphonic a...

Sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H) as a new nanoporous acid catalyst was used in the one-pot synthesis of polyhydroquinolines derivatives via the Hantzsch four component condensation reaction of aldehydes, b-ketoesters, dimedone and ammonium acetate under solvent free conditions with short reaction time in excellent yields. SBA-P...