Synthesis and antiviral activity of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) against peste des petits ruminant virus (PPRV)

AN ECO-FRIENDLY ONE-POT SYNTHESIS OF 4,4'-(ARYLMETHYLENE)BIS(1H-PYRAZOL-5-OLS) USING [Et3NH][HSO4] AS A RECYCLABLE CATALYST

“…The results showed that reactions in solvents take more time and also the yields are low compared to the solvent-free conditions (Table 1, entries [13][14][15][16][17][18]. Water has been identified as an ideal solvent because it is abundant, inexpensive, non-flammable and environmentally benign 40,41 .…”

“…The condensation of aldehydes with two equivalents of 3-methyl-1-phenyl-5-pyrazolone is a conventional chemical approach to 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols). Many catalysts have been used for this transformation such as xanthan sulfuric acid 4 , phosphomolybdic acid 5 , silica sulfuric acid 6 , 3-aminopropylated silica gel 7 , sodium dodecyl sulfate 8 , [Cu(3,4-tmtppa)](MeSO 4 ) 4 9 , PEG-SO 3 H 10 , cellulose sulfuric acid 11 , lithium hydroxide monohydrate 12 , 1,3,5-tris(hydrogensulfato) benzene 13 , sulfuric acid ([3-(3-silicapropyl)sulfanyl]propyl)ester 14 , ethylenediammonium diacetate 15 , [Sipmim]HSO 4 16 , TEBA 17 , ceric ammonium nitrate 18 , silica-bonded S-sulfonic acid 19 , 2-hydroxyethylammonium acetate 20 , 1,3-disulfonic acid imidazolium tetrachloroaluminate 21 and 1-sulfopyridinium chloride 22 . Catalyst-free protocol and the electrocatalytic procedure were also applied to the preparation of 4,4'-(arylmethylene)bis(1H-pyrazol-5-ols) [23][24][25][26] .…”

Fluorous Supported Synthesis of Pyrazolone Derivatives From Allylic Alcohols Using a Palladium-Catalyzed Strategy

“…After stirring at room temperature for 48 h, the crude reaction mixture is diluted in CH 2 Cl 2 (30 mL), washed three times with water and dried over anhydrous sodium sulphate. After filtration, the mixture was evaporated in vacuo, and then dissolved in 10 …”

Poly(4-vinylpyridine)-supported dual acidic ionic liquid: an environmentally friendly heterogeneous catalyst for the one-pot synthesis of 4,4'-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols)

“…16 Moreover, the corresponding 4,4'-(arylmethylene)bis(1H-pyrazol-5-ols) are used as insecticides, 17 pesticides, 18 dyestuffs, 19 and the chelating and extracting reagents for different metal ions. 20 One-pot tandem Knoevenagel-type condensation/Michael reaction between aromatic aldehydes with 2 equivalents of 3-methyl-l-phenyl-5-pyrazolone is one of the most pivotal preparation methods of 4,4'-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols).…”