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A one-pot three-component approach for the synthesis of dihydrofuro[3,2-c]coumarins was developed via the reaction of aryl/hetryl aldehydes, substituted phenacyl bromides and 4-hydroxycoumarin using N,N-diisopropyl ethyl ammonium acetate as the promoting medium.

The synthesis of 14-aryl 14H-dibenzo[a,j]xanthenes is achieved by a simple condensation reaction between β-naphthol with aryl or alkyl aldehydes in an effective synergetic catalytic system created by combining basic bleaching earth clay and PEG-600. The advantages of the present method include catalyst recyclability, superior product yield, a shorter reaction time and the avoidance of hazardous reagents. Synthesized xanthene derivatives were also screened for their antibacterial activity against Staphylococcus aureus (MTCC 96) and Pseudomonas aeruginosa (Wild).

Herein, a fast and convenient protocol for the synthesis of new isoniazid fused chromeno[4,3-b]quinolin was achieved through biomimetic catalysis by cyclodextrin in the water at 60–65 °C. The present investigation involves attractive characteristics such as the use of water as the reaction medium, one-pot conditions, short reaction periods, easy work-up/purification and reduced waste production. This method provides a green route for the synthesis of targeted scaffolds and also a wide substrate scope for several substituted aldehydes to provide good yields of the corresponding products. Furthermore, the catalyst can be easily recovered by simple filtration and reused several times without any substantial loss in activity. Our study also discloses the antimicrobial screening of new chromeno[4,3-b]quinolin-isonicotinamides against four bacterial and three fungal strains.

The present work describes eco-friendly multicomponent protocol for the synthesis in excellent yields of structurally diverse benzylpyrazolyl coumarin 5 (a–s) involving the reaction of 4-hydroxycou...

In the present study, we have developed an efficient and green method for the synthesis of pyrano[2,3-d]pyrimidine-2,4,7-triones employing β-cyclodextrin as a catalyst in aqueous media from substituted aldehydes, barbituric acid and meldrum acid. The reactions were performed under mild conditions to afford biologically active target molecules in excellent yields. All the synthesized compounds are evaluated for their in vitro anticancer activity against HePG-2 (Human liver cancer cell line) and MCF-7 (Human breast cancer cell line). Among them 4c, 4j, 4k, 4l and 4m were active and potent anticancer agents.

Natural products from medicinal plants, either as pure compounds or as standardized extracts, provide unlimited opportunities for new drug leads because of unmatched availability of chemical diversity. The present study is performed to investigate the presence of phytochemicals for using selected medicinal plant such as Abrus precatorius (L.) Soxhlet apparatus was used for the organic solvent extraction. Abrus precatorius (L.) an important medicinal plant is enriched with remarkable highly potent anti-inflammatory, antimicrobial, antioxidant, antifertility, antispermatogenic activity. Metabolites are identified by high resolution mass spectrometry (HR-LCMS). These metabolites are found in various drug compounds used for drug industry as well as in Ayurveda, folk, Homeopathy, Sidha and Unani.

A library of new sulfonyl decahydroacridine-1,8-diones has been efficiently synthesized by the one-pot three-component reactions of 4-(p-tolyl sulfonoxy) benzaldehyde, dimedone, and amines in choli...

The inhibition of D-alanine-D-alanine ligase (Ddl) prevents bacterial growth, which makes this enzyme an attractive and viable target in the urgent search for novel effective antimicrobial drugs. In this work, a series of novel coumarin-linked pyrazoline inhibitors of D-alanine-D-alanine ligase were synthesized and evaluated as inhibitors of Escherichia coli DdlB ligase in order to target resistant strains of bacteria using environmentally benevolent β-cyclodextrin as a supramolecular catalyst via one-pot four component synthesis in water as a green reaction media. All the newly synthesized compounds have been characterized by elemental analysis and various spectroscopic methods. The new procedure has noteworthy advantages including easy work-up, short reaction times, high yields of products and column-free synthesis. The synthesized compounds were evaluated in vitro for their antimicrobial activity. Among the synthesized compounds, namely 3-(5-(4-hydroxy-3-methoxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl)-2H-chromen-2-one (5f) was found to be the most potent D-alanine-D-alanine ligase enzyme inhibitor, with an IC50 value 106 μM, and the compound 3-(5-(p-tolyl)-4,5-dihydro-1H-pyrazol-3-yl)-2H-chromen-2-one (5g) was found to be the second-most potent inhibitor of the DdlB enzyme, with an IC50 value 111 μM against the standard D-cycloserine. In addition, SAR study provided evidence that the –OH, –CH3 and –OCH3 groups at the 4- and 3-position of the coumarins linked to the pyrazolines scaffold increased enzymatic inhibition, while the molecular docking study of most active compounds 5a, 5g, and 5j against DdlB enzyme of E. coli exhibited good binding properties. This work thus highlights the coumarin-linked pyrazoline motif as a very promising tool for the development of novel antimicrobial compounds acting through an interesting bactericidal mechanism of action.

Plant metabolites with therapeutic values provide enormous scope for novel drug leads. In this context several traditional medicinal plants are targeted for phytochemicals identification and characterization worldwide. The current investigation was undertaken to identify metabolites present in seeds of Abrus precatorius (L.), a medicinal plant with potent anti-inflammatory, antimicrobial, antioxidant, antifertility, and antispermatogenic activity. Ethanol extracted seed metabolites were identified by LC-ESI-Q-TOF-MS system equipped with a G4220B pump, G4226A auto sampler and G1316C, and a diode array detector. Metabolites profiling yielded large sets of data were analyzed by METLIN Mass Spectral Database. Metabolomics analysis revealed presence of Desethyletomidate, Butabarbital, 4-aminohippurate, 20α-Dihydroprogesterone glucuronide, Phenethylamine, Etomidate, Oxyquinoline, Norfloxacin, Phenylethylmalonamide (PEMA), and Dihydro streptomycin with typical plants metabolites. The masses of these uncommon metabolites were 216.08, 212.11, 222.09, 492.27, 121.09, 244.12, 145.05, 319.12, 206.10 and 567.28 respectively. These metabolites contribute to various drug preparations used to treat human ailments.

A series of dihydropyranochromenes and chromenopyrimidine-2,5-diones having chromene scaffold were synthesized via efficient multicomponent protocol in aqueous β-cyclodextrin. The reaction is free ...

Simple and green synthetic procedures constitute an important goal in organic synthesis. The combination of multicomponent reactions (MCRs) and unconventional solvents has become a new research direction, which enables simultaneous growth of both MCRs and green solvents toward ideal organic synthesis. In this paper, we have summarized recent results of MCRs obtained in unconventional media using water and β-cyclodextrin, as supramolecular catalyst, for the synthesis of pyrano[2,3-d]-pyrimidinone (4a–q) derivatives. The compounds were evaluated for their in vitro antimicrobial activity. Among the synthesized compounds, compounds 4h, 4m and 4p exhibited higher antimicrobial activity than ciprofloxacin used as the reference drug. Most of the synthesized compounds have good to excellent antimicrobial activity. Furthermore, \ molecular docking study was performed to help understand binding interactions of the most active analogs with C30 carotenoid dehydrosqualene synthase enzyme.

Organopromoter, 2-aminoethanesulfonic acid was used to catalyze the synthesis of a series of structurally intriguing new hybrids thiazolyl acridine-1,8(2H,5H)-diones and dihydropyrido[2,3-d : 6,5-d']dipyrimidine-2,4,6,8(1H,3H,5H,7H)-tetraones for the first time. 2-Aminoethanesulfonic acid is a biobased organopromoter, used to generate four new bonds for the synthesis of new coupled thiazole-based decahydroacridine-1,8-diones. Superior green credentials, operational simplicity, easy work-up and recyclability of the catalyst are the key strengths of this method. The broad substrate scope, mild reaction conditions, short reaction time, cost effectiveness, high atom economy and good to excellent yields make the present method a distinct improvement over existing methods. Spectral (IR, 1 H-NMR,13 C-NMR, Mass) data and elemental analyses confirmed the structures of the titled products. A series of thiazolyl acridine-1,8(2H,5H)-diones and dihydropyrido[2,3-d : 6,5-d']dipyrimidine-2,4,6,8(1H,3H,5H,7H)-tetraones were screened for their antimicrobial activity against four bacterial and three fungal strains.

The catalytic potential of tris(hydroxymethyl)aminomethane (Tromethamine) has been assessed for the one pot three component tandem reaction involving a thiazolylmethoxy phenyl/aromatic carboxaldehyde, substituted amines and thioglycolic acid to form new thiazolyl-4-thiazolidinones and known substituted-4-thiazolidinones. This strategy involves the use of tromethamine as a reusable promoter and water as an eco-friendly reaction medium. The merits of this protocol are high atom economy, mild reaction conditions, good yields of desired products in short reaction times, and reusable reaction medium. The generality and functional tolerance of this convergent and environmentally benign method is demonstrated.