Synthesis, characterization, molecular docking studies and biological activity ofcoumarin linked 2-pyridone heterocycles

In the present paper, the synthesis, characterization, antimicrobial activity and in silico molecular docking study of6-((arylidene)amino)-4-(4-chlorophenyl)-2-oxo-1-((1-(2-oxo-2H-chromen-3-yl)ethylidene)amino)-1,2-dihydropyridine-3,5-dicarbonitriles 4a-o have been reported. Compounds 4d, 4g, 4j, 4k, 4m and 4o show significant activity. Structuredetermination of the synthesized compounds has been done by the standard spectroscopic techniques. It is observed thatbiological activity is influenced by electronic environment of the molecules. Electron withdrawing group at para positionplays a major role for enhancing the biological activity for antibacterial activity and the electron donating group at paraposition for antifungal activity. Compounds 4a-o have been further evaluated for cytotoxicity on HeLa cells. From thecytotoxicity results, compounds have been found to possess low cytotoxicity with potent antimicrobial activity

Synthesis, characterization, molecular docking studies and biological activity of coumarin linked 2-pyridone heterocycles

231-237In the present paper, the synthesis, characterization, antimicrobial activity and in silico molecular docking study of 6-((arylidene)amino)-4-(4-chlorophenyl)-2-oxo-1-((1-(2-oxo-2H-chromen-3-yl)ethylidene)amino)-1,2-dihydropyridine-3,5-dicarbonitriles 4a-o have been reported. Compounds 4d, 4g, 4j, 4k, 4m and 4o show significant activity. Structure determination of the synthesized compounds has been done by the standard spectroscopic techniques. It is observed that biological activity is influenced by electronic environment of the molecules. Electron withdrawing group at para position plays a major role for enhancing the biological activity for antibacterial activity and the electron donating group at para position for antifungal activity. Compounds 4a-o have been further evaluated for cytotoxicity on HeLa cells. From the cytotoxicity results, compounds have been found to possess low cytotoxicity with potent antimicrobial activity

Design and synthesis of new quinoline hybrid derivatives and their antimicrobial, antimalarial and antitubercular activities

986-998All the molecules have been designed on the basis of previously reported active pharmacophores via molecular hybridization. A convenient protocol for the preparation of N-((2-(piperazin-1-yl) quinolin-3-yl)methyl)aniline derivatives via mutli-step synthesis has been described. Spectral analysis using Mass, 1H and 13C NMR spectral techniques have been studied in order to confirm the structure of synthesized end molecules. All synthesized compounds have been screened for in vitro antimicrobial, antimalarial and antitubercular activities. Structural activity relationship study (SAR) have also been discussed. Interestingly, target molecules are found to show good to excellent antibacterial, antifungal and antimalarial potency

Facile, eco-friendly and one-pot synthesis of 3,4-disubstituted isoxazol- 5(4<em>H</em>)-ones using starch solution as a reaction media

890-896A one-pot three-component reaction of ethyl acetoacetate with hydroxylamine hydrochloride and various aromatic aldehydes has been developed using starch solution as a reaction media. Starch solution has been employed as an environmentally benign and commercially available catalytic system for this synthesis. This cyclo-condensation reaction has been performed in aqueous ethanol as an environmentally benign solvent at 90°C as well as under microwave irradiation (MWI, 300 W) giving 3,4-disubstituted isoxazol-5(4H)-one derivatives in excellent yields. The use of a nontoxic, reusable and biodegradable catalytic system is one of the superior advantages of this protocol. The superior features of the present methodology are mild reaction conditions, excellent yields, high atom-economy, easy work-up process, short reaction times and use of microwave irradiation conditions

Glycerol mediated green and one-pot synthesis of 6-amino-1,4-dihydropyrano[2,3-<i>c</i>]-pyrazole-5-carbonitriles under catalyst free conditions

999-1006A concise, facile and straightforward synthetic protocol has been described for the preparation of 6-amino-1,4-dihydropyrano[2,3-c]-pyrazole-5-carbonitrile derivatives by a one-pot, three-component reaction of ethyl acetoacetate, hydrazine hydrate, aryl aldehydes and malononitrile in glycerol as a green and reusable reaction media under catalyst free condition. The corresponding 6-amino-1,4-dihydropyrano[2,3-c]-pyrazole-5-carbonitriles have been obtained with good to excellent yields (86-92%). This protocol is highly efficient due to its mild reaction conditions, operational simplicity, use of inexpensive, eco-friendly and green reaction media, catalyst-free conditions and absence of toxic organic solvents

An efficient protocol for the one-pot four-component synthesis of 6-amino-1, 4-dihydropyrano[2,3-<em>c</em>]-pyrazole-5-carbonitrile derivatives using starch solution as a reaction media

576-582An efficient, high-yielding and rapid protocol has been developed for the synthesis of 6-amino-1,4-dihydropyrano [2,3-c]pyrazol-5-carbonitrile derivatives through four-component, one-pot cyclocondensation reaction of ethyl acetoacetate, hydrazine hydrate, aldehydes and malononitrile utilizing starch solution as a highly efficient homogenous catalyst. The use of a nontoxic, reusable and biodegradable catalyst is one of the superior advantages of this protocol. Short reaction times, mild conditions, excellent product yields, simple work-up procedure and non use of toxic organic solvents are added advantages of this procedure

Design and synthesis of new quinoline hybrid derivatives and their antimicrobial, antimalarial and antitubercular activities

All the molecules have been designed on the basis of previously reported active pharmacophores via molecular hybridization. A convenient protocol for the preparation of N-((2-(piperazin-1-yl) quinolin-3-yl)methyl)aniline derivatives via mutli-step synthesis has been described. Spectral analysis using Mass, 1H and 13C NMR spectral techniques have been studied in order to confirm the structure of synthesized end molecules. All synthesized compounds have been screened for in vitro antimicrobial, antimalarial and antitubercular activities. Structural activity relationship study (SAR) have also been discussed. Interestingly, target molecules are found to show good to excellent antibacterial, antifungal and antimalarial potency. 

Synthesis of pyrazolo[4ʹ,3ʹ:5,6]pyrano[2,3-<em>d</em>]pyrimidine derivatives and their antimicrobial, antimalarial and antituberculosis evaluation

997-1005This article deals with the synthesis of a new pyrazolo[4ʹ,3ʹ:5,6]pyrano[2,3-d]pyrimidine derivatives by the reaction of 1,4-dihydropyrano[2,3-c]-pyrazole-5-carbonitriles with ethyl cyanoacetate catalyzed by triethylamine (TEA) in ethanol under reflux conditions. All the synthesized compounds have been checked for their purity by melting point and TLC, and have been characterized through various spectroscopic techniques such as 1H and 13C NMR, IR, ESI-MS and elemental analysis. All synthesized compounds have been screened for antimicrobial, antimalarial and antituberculosis activity

Green synthesis of pyrazolo[4,3-<em>d</em>]isoxazol derivatives and their antimicrobial, antimalarial and antituberculosis evaluation

1033-1041This article deals with the synthesis of new pyrazolo[4,3-d]isoxazol derivatives by utilizing 3,4-disubstituted isoxazol-5(4H)-ones and thiosemicarbazide catalyzed by triethylamine in PEG-400 under MWI at 300 W as well as under thermal heating at 90°C. All the synthesized compounds have been characterized by various spectroscopic techniques such as 1H and 13C NMR, IR, ESI-MS and elemental analysis. All the synthesized compounds have been screened for antimicrobial, antimalarial and antituberculosis activities