A rapid, efficient, and high-yielding synthesis of 4,4′-(arylmethylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives catalyzed by 12-tungstophosphoric acid (H3PW12O40)

Pyrazolone-type compounds: synthesis andin silicoassessment of antiviral potential against key viral proteins of SARS-CoV-2

“…Generally, the literature on these particular types of compounds is relatively scarce, and the research is mainly focused on the development of novel eco-friendly synthetic methods employing various catalysts, mostly ionic liquids and nanoparticles. [45][46][47][48][49][50][51][52] Following such a trend, the synthesis of pyrazolone analogues a-t was accomplished in the reactions of 5-methyl-2,4-dihydro-3H-pyrazol-3-one with different aromatic aldehydes in the presence of diethanolamine as a catalyst, and in ethanol and under reux. To optimise reaction conditions, the model reaction between benzaldehyde and 5-methyl-2,4-dihydro-3Hpyrazol-3-one was investigated in the presence of various catalysts and solvents (Table 1).…”

“…To our knowledge, crystal data on these particular compounds are insufficient. Moreover, all articles related to these compounds presented the OH-tautomeric forms of both pyrazolone rings, [45][46][47][48][49][50][51][52] including the crystal structure of compound a. 57 Single crystal X-ray analysis shows that the compound consists of a substituted phenyl ring and two 3-methyl-5-pyrazolone rings connected through the benzyl C1 atom.…”

Synthesis of New Pyrimido[4′,5′:3,4]pyrazolo[1,2‐b]phthalazine‐4,7,12‐triones: Derivatives of a New Heterocyclic Ring System

“…Because of these important properties, interest has arisen in our group in the construction of such heterocycles and the exploration of their synthetic pathways [24][25][26][27][28][29][30][31][32][33][34]. In connection with these studies, we report herein our investigations in the synthesis of 2-alkyl-5-aryl-3, 5-dihydro-4H-pyrimido[4 0 ,5 0 :3,4]pyrazolo[1,2-b]phthalaz ine-4,7,12-triones 3a-h, members of a new N-heterocyclic ring system, through the reaction of 3-amino-1-aryl-5,10dioxo-5,10-dihydro-1H-pyrazolo[1,2-b]phthalazine-2-car bonitriles 1a-d with aliphatic carboxylic acids 2a and 2b in the presence of phosphoryl chloride (POCl 3 ) (Scheme 1).…”

Another application of (NH4)42[MoVI72MoV60O372(CH3COO)30(H2O)72] as a highly efficient recyclable catalyst for the synthesis of dihydropyrano[3,2‐c]chromenes

“…Polyoxometalates (POMs) are a large class of metal oxide clusters of early transition metals, typically W(VI), V(V), Mo(VI), Nb(V) and Ta(V), bridged by oxygen atoms. They are of proven value in catalysis, magnetism, materials science and biomedicine, because they are diverse and highly modifiable in size, shape, charge density, acidity and reversible redox potential. A number of very large POM anions have been synthesized and structurally characterized.…”