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Green protocols for the syntheses of 3,3′-arylidenebis-4-hydroxycoumarins and dimethyl ((substituted phenyl) (phenylamino)methyl) phosphonates have been first time developed using biocatalyst, CAL-B (lipase). These are carried at room temperature under stirring and are convenient and cost effective. The developed protocols are environmentally acceptable and are giving better to excellent yields of the titled products.

Substituted phenacyl chlorides (1a–f) were cyclocondensed with nucleophiles thiourea (2a) and thiobenzamide (2b) in presence of baker’s yeast (Saccharomyces cerevisiae) as whole-cell enzyme source in acetonitrile at room temperature to obtain 4-(4-substituted phenyl)thiazol-2-amines (3a–f) and 4-(substituted phenyl)-2-phenylthiazoles (4a–f), respectively. Moreover, substituted phenacyl chlorides also reacted with nucleophiles 2-amino-1,3,4-thiadiazole (2c), o-phenylenediamine (2d), 1-amino-2-mercapto-5-phenyl triazole (2e), and pyridin-2-amine (2f) at room temperature in presence of baker’s yeast to give fused heterocycles 6-(4-substituted phenyl)-2-phenylimidazo[2,1-b][1,3,4]thiadiazoles (5a–f), 2-(4-substituted phenyl)quinoxalines (6a–f), 6-(4-substituted phenyl)-3-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines (7a–f), and 2-(4-substituted phenyl)H-imidazo[1,2-a]pyridines (8a–f), respectively. The experimental conditions for these cyclocondensations were optimized to obtain the biodynamic heterocycles in high yield. The unique features of this work are use of baker’s yeast as a cheap and readily available natural source of biocatalyst, noticeable rate acceleration, convenient route to products, cost effectiveness, and scalability.

We report synthesis and in vivo antihyperglycemic evaluation of new 3-substituted phenyl-2-(4-(tetrazolo[1,5-a]quinolin-4-ylmethoxy)phenyl)thiazolidin-4-ones (8a–l). The title 4-thiazolidinones were synthesized by one-pot cyclocondensation of new 4-(tetrazolo[1,5-a]quinolin-4-ylmethoxy)benzaldehyde (5), anilines, and mercaptoacetic acid in PEG-400. The required aldehyde (5) was also synthesized, starting from 2-chloroquinoline-3-carbaldehyde via a successive multistep route. The newly synthesized products were thoroughly characterized based on their spectral data. Amongst them, compounds 8a–g, j exhibited notable in vivo antihyperglycemic activity. Compounds 8f, g showed percentage improvement in oral glucose tolerance of 18.9 and 20.7, respectively, compared with 28.3 for the reference metformin.

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.