One-pot rapid synthesis of thiazole-substituted pyrazolyl-4-thiazolidinones mediated by diisopropylethylammonium acetate

Abstract

A convenient one-pot, rapid and scalable synthetic protocol has been developed for recently reported anti-inflammatory agents, thiazole-substituted pyrazolyl-4-thiazolidinones. Quantitative multicomponent cyclocondensation of 3-(4-methyl-2-substituted thiazol-5-yl)-1-phenyl-1H-pyrazole-4-carbaldehydes (5a, b), amines and mercaptoacetic acid has been carried out in safer medium, diisopropylethylammonium acetate, at room temperature. The optimisation details of the developed novel protocol are recorded.

Synthesis, antimicrobial, and antioxidant activities of new pyridyl‐ and thiazolyl‐bearing carbohydrazides

“…The obtained 4‐methyl‐2‐(2‐propylpyridin‐4‐yl)thiazole‐5‐carboxylate ( 3 ) and excess of hydrazine hydrate were refluxed in ethanol for 4 hr to furnish a key intermediate, 4‐methyl‐2‐(2‐propylpyridin‐4‐yl)thiazole‐5‐carbohydrazide ( 4 ), with 78% yield. The condensations of aromatic aldehydes ( 5a‐l ) and 4‐methyl‐2‐(2‐propylpyridin‐4‐yl)thiazole‐5‐carbohydrazide ( 4 ) were performed in diisopropylethylammonium acetate (DIPEAc) to obtain the corresponding substituted ( E )‐ N ′‐benzylidene‐4‐methyl‐2‐(2‐propylpyridin‐4‐yl)thiazole‐5‐carbohydrazides ( 6a ‐ l ) with 80–90% yields. The products obtained were purified by recrystallization in ethanol.…”

Synthesis, Anticancer and Antimicrobial Evaluation of New (E)‐N′‐Benzylidene‐2‐(2‐ethylpyridin‐4‐yl)‐4‐methylthiazole‐5‐carbohydrazides

“…The condensation of aromatic aldehydes ( 5 a‐n ) and 2‐(2‐ethylpyridin‐4‐yl)‐4‐methylthiazole‐5‐carbohydrazide ( 4 ) were carried in diisopropylethylammonium acetate (DIPEAc) to obtain the respective substituted ( E )‐ N ′‐benzylidene‐2‐(2‐ethylpyridin‐4‐yl)‐4‐methylthiazole‐5‐carbohydrazides ( 6 a‐n ) with better to excellent yields. The DIPEAc is displaying dual role as a medium and catalyst in acceleration of the condensation of the acid hydrazide and aldehydes to furnish the corresponding substituted carbohydrazides ( 6 a‐n ) rapidly . The products obtained were purified by crystallization and their structures have been elucidated by spectral analyses (Incorporated in supporting information file) and the physical data is presented in Table .…”

Application of a novel Deep Eutectic Solvent as a capable and new catalyst for the synthesis of tetrahydropyridines and 1,3-thiazolidin-4-ones

“…Speci cally, ve-membered heterocycles with two heteroatoms have received particular attention, having proven utility in medicinal chemistry [31]. 1,3-Thiazolidin-4-ones are important class of compounds due to their biological pro les like anti-tubercular [32], anti-microbial [33], anti-in ammatory [34], anti-histaminic [35], anti-hepatitis [36], HIV inhibitors [37], anti-hyper-glycemic [38], anti-hypertensive [39], anti-convulsant [40], anti-fungal [41], anti-oxidant [42], and anti-proliferative [43] activity.…”