Bhaskar Dawane | Swami Ramanand Teerth Marathwada University, Nanded (original) (raw)
Papers by Bhaskar Dawane
The short, easy and total synthesis of Murrayanine (1), Mukonine (2), carbazole alkaloids were e... more The short, easy and total synthesis of Murrayanine (1), Mukonine (2), carbazole alkaloids were elaborated, based on a regioselective buchwald coupling of methyl 4-bromo-3-methoxybenzoate with aniline and successive transformation into the corrsponding carbazole alkaloids by oxidative coupling followed by cyclization of the phenyl and aryl rings.
A simple and efficient method is described for the synthesis of some novel acridine derivatives 3... more A simple and efficient method is described for the synthesis of some novel acridine derivatives 3 by the one-pot condensation of sartalone 1, substituted aldehyde 2, and liquor ammonia in alkaline poly ethylene glycol (PEG-400) as green reaction solvent at mild temperature. The structures of the products were confirmed on the basis spectral and analytical data. These newly synthesized compounds were evaluated for in vitro antibacterial activity. Most of the compounds showed potent activity.
Archives of Applied Science Research, 2011
Efficient and clean procedure for N-formylation of amines has been carried out under neat reactio... more Efficient and clean procedure for N-formylation of amines has been carried out under neat reaction condition. Environmentally friendly process furnishing moderate to excellent yields of product and simple work-up giving pure products are attractive features of the reaction.
![Research paper thumbnail of DTP/SiO2:An Efficient And Reusable Heterogeneous Catalyst For synthesis of dihydropyrano[3,2-c]chromene-3-carbonitrile derivatives](https://attachments.academia-assets.com/113056511/thumbnails/1.jpg)
](An efficient and convenient method has been developed for the synthesis of 2-amino-5-oxo-4-phenyl... more An efficient and convenient method has been developed for the synthesis of 2-amino-5-oxo-4-phenyl-4, 5-dihydropyrano[3,2-c]chromene-3-carbonitrile derivatives from one-pot multicomponent reaction between 4-hydroxy-2H-chromen-2-one, aromatic aldehydes and malononitrile catalyzed by DTP/SiO2 as an efficient and reusable heterogeneous catalyst. The current method provides adavtages over reported method viz simple operational procedure, easy isolation and recyclability of the catalyst, environmental benign, reduced reaction time and superior yield.
International Journal of Scientific Research in Science and Technology, 2017
We wish to describe an efficient and rapid synthesis of isoxazolines by the reaction of substitut... more We wish to describe an efficient and rapid synthesis of isoxazolines by the reaction of substituted pyrazol-5-one were condensed with hydroxylamine hydrochloride in presence of clay (pH =12.5) and PEG-400 as a green reaction media. Herein, we report the conventional condensation method of substituted pyrazol-5-one with hydroxylamine hydrochloride in PEG-400 as reaction solvent at mild reaction condition. Structures of the synthesized compounds were confirmed by the spectral analysis. Furthermore, all the synthesized compounds were evaluated for their antimicrobial screening against several pathogenic representatives, these newly synthesized compounds were screened for their antimicrobial activity against bacterial strain Escherichia coli (MTCC-443), Bacillus subtilis (MTCC-441), Staphylococcus aureus (MTCC-96) and Salmonella typhi. (MTCC-98). The antifungal activity was evaluated against Aspergillus niger (MTCC-1781), Aspergillus flavus (MTCC-3008), Candida albicans (MTCC-227) and Penicillium chrysogenum (MTCC-160).The result revealed that most of the compounds showed good to moderate Antimicrobial screening. The major advantages of this protocol are it gives excellent yields of products, work up procedure and isolation is easier, Procedure is green and environmentally benign, shorter reaction times.
Research on Chemical Intermediates, 2021
Herein we describe a new convenient strategy for the synthesis of substituted thiazolopyrimidines... more Herein we describe a new convenient strategy for the synthesis of substituted thiazolopyrimidines. The present approach delivers the use of silica-supported sodium carbonate (SSC) as a recyclable heterogeneous catalyst in PEG- 400 solvent. The described synthetic route offers an easy access for the synthesis of titled compounds through green chemistry protocols.
New Journal of Chemistry, 2021
A direct metal-free approach for the synthesis of novel sulfenylated 2-aminothiazole and imidazot... more A direct metal-free approach for the synthesis of novel sulfenylated 2-aminothiazole and imidazothiazole derivatives at room temperature is reported via an in situ-generated electrophilic thiolating agent.
Medicinal Chemistry Research, 2017
Diabetes is embracing the human population in logarithmic fashion both in developed as well as de... more Diabetes is embracing the human population in logarithmic fashion both in developed as well as developing countries. Aldose reductase is one of the important enzymes of polyol pathway of sugar metabolism in humans. Aldose reductase inhibition has been identified as one of the important target for developing novel antidiabetic agents. In this report, we present an effective synthesis of 7-(substituted phenyl) chromeno-pyrano [2,3-d]pyrimidine-6,8,10-(7H,9H,11H)-trione derivatives and demonstrate their aldose reductase inhibition potential in order to identify novel schemes for finding putative aldose reductase inhibitors. The antioxidant activity of all the synthesized compounds with negligible toxicity demonstrates the biological efficacy of the synthesized compounds. The in silico molecular docking and structural analysis of docked poses conducted in the current investigation sheds light on the structural rationale of the observed aldose reductase inhibition by all the newly synthesized compounds. Keywords Chromeno-pyrano pyrimidine trione derivatives • Aldose reductase • Molecular docking • Antioxidant activity • Hemolytic activity * Bhaskar S.
Journal of Surface Science and Technology, 2016
Novel biobased epoxy resins were prepared from waste vegetable oil by epoxidation using hydrogen ... more Novel biobased epoxy resins were prepared from waste vegetable oil by epoxidation using hydrogen peroxide in acetic acid. Biobased epoxy resins were prepared by reaction of acid hardeners such as citric acid (B1), tartaric acid (B2), succinic anhydride (B3) and sebacic acid (B4) with epoxydised waste vegetable oil. The intrinsic viscosities were in the range of 0.06 to 0.70 (dL/g) and thermally stable up to 350°C. Solution cast thin films are transparent except B4. The resin films were completely biodegraded by using bacterial granules (made up of bacterial consortia) within 14-135 days. The resin [B1] was found to be biocompatible based on blood clotting studies.
Asian Journal of Research in Chemistry, 2010
In the present communication, a series of some new pyrazole based chalcones were prepared by the ... more In the present communication, a series of some new pyrazole based chalcones were prepared by the conventional Claisen-Schmidt condensation method under mild reaction condition. All the synthesized products were characterized by the spectroscopic and analytical measurements. Furthermore, all the synthesized compounds were screened for their antimicrobial activity.
A simple and efficient synthesis of 1, 2, 4-triazine derivatives is described by the condensation... more A simple and efficient synthesis of 1, 2, 4-triazine derivatives is described by the condensation of substituted 4-(2-chloro-quinoline-3yl methylene)-2-[phenyl-4H-oxazol-5-one and phenyl hydrazine an equimolar sodium acetate and acetic acid as a solvent. The newly synthesized compounds were evaluated for their antimicrobial activity.
Indian journal of biochemistry & biophysics, 2006
L-Asparaginase shows antileukemic activity and is generally administered in the body in combinati... more L-Asparaginase shows antileukemic activity and is generally administered in the body in combination with other anticancer drugs like pyrimidine derivatives. In the present study, L-asparaginase was purified from a bacteria Erwinia carotovora and the effect of a dihydropyrimidine derivative (1-amino-6-methyl-4-phenyl-2-thioxo, 1,2,3,4-tetrahydropyrimidine-5-carboxylic acid methyl ester) was studied on the kinetic parameters Km and Vmax of the enzyme using L-asparagine as substrate. The enzyme had optimum activity at pH 8.6 and temperature 35 degrees C, both in the absence and presence of pyrimidine derivative and substrate saturation concentration at 6 mg/ml. For the enzymatic reaction in the absence and presence (1 to 3 mg/ml) of dihydropyrimidine derivative, Km values were 7.14, 5.26, 4.0, and 5.22 M, and Vmax values were 0.05, 0.035, 0.027 and 0.021 mg/ml/min, respectively. The kinetic values suggested that activity of enzyme was enhanced in the presence of dihydropyrimidine deriv...
Research on Chemical Intermediates, 2014
A green, efficient, and simple method for synthesis of 5,6,7,8-tetrahydroquinoline-3-carbonitrile... more A green, efficient, and simple method for synthesis of 5,6,7,8-tetrahydroquinoline-3-carbonitrile derivatives via one-pot three-component condensation of 2,6-bis(substituted benzylidene)cyclohexanone, arylamines/substituted 2-aminothiazoles, and malononitrile in the presence of bleaching earth clay pH 12.5 (basic catalyst) as a recyclable and green catalyst in PEG-400 is described. Catalyst recyclability, good to excellent product yield, shorter reaction time, and avoidance of hazardous reagents are the main advantages of this methodology.
Medicinal Chemistry Research, 2014
Research on Chemical Intermediates, 2014
We report bleaching earth clay pH 12.5/PEG-400 as an efficient catalytic system for preparation o... more We report bleaching earth clay pH 12.5/PEG-400 as an efficient catalytic system for preparation of α,β-unsaturated ketones (chalcones). The method presents one or more advantages over existing methodologies such as shorter reaction time, excellent yield, and low cost. All synthesized products were characterized by spectroscopic and analytical measurements.
Medicinal Chemistry Research, 2014
ABSTRACT Synthesis of novel thiophene substituted isoxazoline libraries is currently of high inte... more ABSTRACT Synthesis of novel thiophene substituted isoxazoline libraries is currently of high interest. Here, we have reported detailed syntheses of 2,5-dichlorothiophene, 5-chloro-2-(benzylthio)thiophene, and 5-chlorothiophene-2-sulphonamide substituted analogs of isoxazoline from chalcones catalyzed by NaOH in PEG-400 as green solvent. In vitro antimycobacterial and antimicrobial activity of newly synthesized compounds were investigated. Compounds 2j, 2k, and 2l showed excellent activity against Mycobacterium tuberculosis and other Mycobacterium strains tested. Compounds 2a–2c, 2i showed excellent activity against all bacterial and fungal species tested. The isoxazoline scaffold synthesized in the present study may be useful in the development of novel new antimicrobial agents. Graphical abstract An efficient synthesis of isoxazoline libraries of thiophene analogs and its antimycobacterial investigation.
![Research paper thumbnail of Green approach towards synthesis of substituted pyrazole-1,4-dihydro,9-oxa,1,2,6,8-tetrazacyclopentano[b]naphthalene-5-one derivatives as antimycobacterial agents](https://attachments.academia-assets.com/113056501/thumbnails/1.jpg)
](Medicinal Chemistry Research, 2013
In the present communication, a simple and efficient synthesis of some new Pyrano-[2,3-c]-pyrazol... more In the present communication, a simple and efficient synthesis of some new Pyrano-[2,3-c]-pyrazoles derivatives are described by the one-pot condensation of a mixture of 3-methyl-1-phenyl-1H-pyrazole-5(4H)-one, substituted heterylaldehydes and malononitriles in polyethylene glycol (PEG-400) as green reaction solvent, further reacted with substituted acetophenones in the presence of polyethylene glycol (PEG-400) to form naphthalene analogues. Synthesis of novel substituted naphthalene analogues libraries are currently of high interest. The chemical structures of newly synthesized compounds were confirmed by IR, 1 H NMR and Mass spectral analysis. In vitro antimycobacterial activities of newly synthesized compounds were investigated against Mycobacterium smegmatis, Mycobacterium pheli and Mycobacterium tuberculosis species. The result revealed that most of the compounds showed good to moderate Antimycobacterial activity.
Journal of Heterocyclic Chemistry, 2009
magnified imagePoly(ethylene glycol) (PEG‐400) has been used as sustainable, nonvolatile, and env... more magnified imagePoly(ethylene glycol) (PEG‐400) has been used as sustainable, nonvolatile, and environmental friendly reaction solvent for the synthesis of title compounds. Various diaryl pyrido[3,2‐c]coumarins have been synthesized in one step by reacting 4‐hydroxy‐7‐methyl‐coumarin with α,β‐unsaturated ketones in the presence of ammonium acetate. Further, in vitro antimicrobial (antibacterial and antifungal) activities of the compounds were screened against different pathogens. The results revealed that most of them showed potent activity. J. Heterocyclic Chem., (2010).
Journal of Enzyme Inhibition and Medicinal Chemistry, 2008
Xanthine dehydrogenase (XDH) is responsible for the pathological condition called Gout. In the pr... more Xanthine dehydrogenase (XDH) is responsible for the pathological condition called Gout. In the present study different flavones synthesized from chalcone were evaluated in vitro for their inhibitory activity. Inhibitory activity of flavones on XDH was determined in terms of inhibition of uric acid synthesis from Xanthine. The enzymatic activity was found maximum at pH 7.5 and temperature 408C. The flavones 6-chloro-2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F 1) and 6-chloro-7methyl-2-[3-(4-chloro-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one(F 2),were noncompetitive and competitive inhibitor with Ki values 1.1 and 0.22 respectively. The flavones (F 1), (F 2), 6-chloro-2-[3-(4-chloro-phenyl)-1phenyl-1-Hpyrazol-4-yl]-chromen-4-one(F 3), 8-bromo-6-chloro-2-[3-(4-chloro-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F 4), 2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F 5) and 6-methyl-2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F 6) were also screened for their antimicrobial activity, measured in terms of zone of inhibition. A broad spectrum antifungal activity was obtained against Trichoderma viridae, Candida albicans, Microsporum cannis, Penicillium chrysogenum and Fusarium moniliformae. In case of Aspergillus niger and Aspergillus flavous only spore formation was affected, while antibacterial activity was observed against Staphylococcus aureus, Bacillus subtilis and Serratia marsecens only. The flavones were further analyzed for quantitative structural activity relationship study (QSAR) by using PASS, online software to determine their Pa value. Toxicity and drug relevant properties were revealed by PALLAS software in terms of their molecular weight. Log P values were also studied. The result showed both the F 1 and F 2 flavones as antigout and therefore supports the development of novel drugs for the treatment of gout.
Green Chemistry Letters and Reviews, 2010
An efficient and convenient procedure for the synthesis of thiazole derivatives from α-haloketone... more An efficient and convenient procedure for the synthesis of thiazole derivatives from α-haloketone, thiourea and substituted acetophenones using polyethylene glycol-400 as a green and recyclable solvent is described. Significant rate enhancement and improved yields have been observed.
The short, easy and total synthesis of Murrayanine (1), Mukonine (2), carbazole alkaloids were e... more The short, easy and total synthesis of Murrayanine (1), Mukonine (2), carbazole alkaloids were elaborated, based on a regioselective buchwald coupling of methyl 4-bromo-3-methoxybenzoate with aniline and successive transformation into the corrsponding carbazole alkaloids by oxidative coupling followed by cyclization of the phenyl and aryl rings.
A simple and efficient method is described for the synthesis of some novel acridine derivatives 3... more A simple and efficient method is described for the synthesis of some novel acridine derivatives 3 by the one-pot condensation of sartalone 1, substituted aldehyde 2, and liquor ammonia in alkaline poly ethylene glycol (PEG-400) as green reaction solvent at mild temperature. The structures of the products were confirmed on the basis spectral and analytical data. These newly synthesized compounds were evaluated for in vitro antibacterial activity. Most of the compounds showed potent activity.
Archives of Applied Science Research, 2011
Efficient and clean procedure for N-formylation of amines has been carried out under neat reactio... more Efficient and clean procedure for N-formylation of amines has been carried out under neat reaction condition. Environmentally friendly process furnishing moderate to excellent yields of product and simple work-up giving pure products are attractive features of the reaction.
An efficient and convenient method has been developed for the synthesis of 2-amino-5-oxo-4-phenyl... more An efficient and convenient method has been developed for the synthesis of 2-amino-5-oxo-4-phenyl-4, 5-dihydropyrano[3,2-c]chromene-3-carbonitrile derivatives from one-pot multicomponent reaction between 4-hydroxy-2H-chromen-2-one, aromatic aldehydes and malononitrile catalyzed by DTP/SiO2 as an efficient and reusable heterogeneous catalyst. The current method provides adavtages over reported method viz simple operational procedure, easy isolation and recyclability of the catalyst, environmental benign, reduced reaction time and superior yield.
International Journal of Scientific Research in Science and Technology, 2017
We wish to describe an efficient and rapid synthesis of isoxazolines by the reaction of substitut... more We wish to describe an efficient and rapid synthesis of isoxazolines by the reaction of substituted pyrazol-5-one were condensed with hydroxylamine hydrochloride in presence of clay (pH =12.5) and PEG-400 as a green reaction media. Herein, we report the conventional condensation method of substituted pyrazol-5-one with hydroxylamine hydrochloride in PEG-400 as reaction solvent at mild reaction condition. Structures of the synthesized compounds were confirmed by the spectral analysis. Furthermore, all the synthesized compounds were evaluated for their antimicrobial screening against several pathogenic representatives, these newly synthesized compounds were screened for their antimicrobial activity against bacterial strain Escherichia coli (MTCC-443), Bacillus subtilis (MTCC-441), Staphylococcus aureus (MTCC-96) and Salmonella typhi. (MTCC-98). The antifungal activity was evaluated against Aspergillus niger (MTCC-1781), Aspergillus flavus (MTCC-3008), Candida albicans (MTCC-227) and Penicillium chrysogenum (MTCC-160).The result revealed that most of the compounds showed good to moderate Antimicrobial screening. The major advantages of this protocol are it gives excellent yields of products, work up procedure and isolation is easier, Procedure is green and environmentally benign, shorter reaction times.
Research on Chemical Intermediates, 2021
Herein we describe a new convenient strategy for the synthesis of substituted thiazolopyrimidines... more Herein we describe a new convenient strategy for the synthesis of substituted thiazolopyrimidines. The present approach delivers the use of silica-supported sodium carbonate (SSC) as a recyclable heterogeneous catalyst in PEG- 400 solvent. The described synthetic route offers an easy access for the synthesis of titled compounds through green chemistry protocols.
New Journal of Chemistry, 2021
A direct metal-free approach for the synthesis of novel sulfenylated 2-aminothiazole and imidazot... more A direct metal-free approach for the synthesis of novel sulfenylated 2-aminothiazole and imidazothiazole derivatives at room temperature is reported via an in situ-generated electrophilic thiolating agent.
Medicinal Chemistry Research, 2017
Diabetes is embracing the human population in logarithmic fashion both in developed as well as de... more Diabetes is embracing the human population in logarithmic fashion both in developed as well as developing countries. Aldose reductase is one of the important enzymes of polyol pathway of sugar metabolism in humans. Aldose reductase inhibition has been identified as one of the important target for developing novel antidiabetic agents. In this report, we present an effective synthesis of 7-(substituted phenyl) chromeno-pyrano [2,3-d]pyrimidine-6,8,10-(7H,9H,11H)-trione derivatives and demonstrate their aldose reductase inhibition potential in order to identify novel schemes for finding putative aldose reductase inhibitors. The antioxidant activity of all the synthesized compounds with negligible toxicity demonstrates the biological efficacy of the synthesized compounds. The in silico molecular docking and structural analysis of docked poses conducted in the current investigation sheds light on the structural rationale of the observed aldose reductase inhibition by all the newly synthesized compounds. Keywords Chromeno-pyrano pyrimidine trione derivatives • Aldose reductase • Molecular docking • Antioxidant activity • Hemolytic activity * Bhaskar S.
Journal of Surface Science and Technology, 2016
Novel biobased epoxy resins were prepared from waste vegetable oil by epoxidation using hydrogen ... more Novel biobased epoxy resins were prepared from waste vegetable oil by epoxidation using hydrogen peroxide in acetic acid. Biobased epoxy resins were prepared by reaction of acid hardeners such as citric acid (B1), tartaric acid (B2), succinic anhydride (B3) and sebacic acid (B4) with epoxydised waste vegetable oil. The intrinsic viscosities were in the range of 0.06 to 0.70 (dL/g) and thermally stable up to 350°C. Solution cast thin films are transparent except B4. The resin films were completely biodegraded by using bacterial granules (made up of bacterial consortia) within 14-135 days. The resin [B1] was found to be biocompatible based on blood clotting studies.
Asian Journal of Research in Chemistry, 2010
In the present communication, a series of some new pyrazole based chalcones were prepared by the ... more In the present communication, a series of some new pyrazole based chalcones were prepared by the conventional Claisen-Schmidt condensation method under mild reaction condition. All the synthesized products were characterized by the spectroscopic and analytical measurements. Furthermore, all the synthesized compounds were screened for their antimicrobial activity.
A simple and efficient synthesis of 1, 2, 4-triazine derivatives is described by the condensation... more A simple and efficient synthesis of 1, 2, 4-triazine derivatives is described by the condensation of substituted 4-(2-chloro-quinoline-3yl methylene)-2-[phenyl-4H-oxazol-5-one and phenyl hydrazine an equimolar sodium acetate and acetic acid as a solvent. The newly synthesized compounds were evaluated for their antimicrobial activity.
Indian journal of biochemistry & biophysics, 2006
L-Asparaginase shows antileukemic activity and is generally administered in the body in combinati... more L-Asparaginase shows antileukemic activity and is generally administered in the body in combination with other anticancer drugs like pyrimidine derivatives. In the present study, L-asparaginase was purified from a bacteria Erwinia carotovora and the effect of a dihydropyrimidine derivative (1-amino-6-methyl-4-phenyl-2-thioxo, 1,2,3,4-tetrahydropyrimidine-5-carboxylic acid methyl ester) was studied on the kinetic parameters Km and Vmax of the enzyme using L-asparagine as substrate. The enzyme had optimum activity at pH 8.6 and temperature 35 degrees C, both in the absence and presence of pyrimidine derivative and substrate saturation concentration at 6 mg/ml. For the enzymatic reaction in the absence and presence (1 to 3 mg/ml) of dihydropyrimidine derivative, Km values were 7.14, 5.26, 4.0, and 5.22 M, and Vmax values were 0.05, 0.035, 0.027 and 0.021 mg/ml/min, respectively. The kinetic values suggested that activity of enzyme was enhanced in the presence of dihydropyrimidine deriv...
Research on Chemical Intermediates, 2014
A green, efficient, and simple method for synthesis of 5,6,7,8-tetrahydroquinoline-3-carbonitrile... more A green, efficient, and simple method for synthesis of 5,6,7,8-tetrahydroquinoline-3-carbonitrile derivatives via one-pot three-component condensation of 2,6-bis(substituted benzylidene)cyclohexanone, arylamines/substituted 2-aminothiazoles, and malononitrile in the presence of bleaching earth clay pH 12.5 (basic catalyst) as a recyclable and green catalyst in PEG-400 is described. Catalyst recyclability, good to excellent product yield, shorter reaction time, and avoidance of hazardous reagents are the main advantages of this methodology.
Medicinal Chemistry Research, 2014
Research on Chemical Intermediates, 2014
We report bleaching earth clay pH 12.5/PEG-400 as an efficient catalytic system for preparation o... more We report bleaching earth clay pH 12.5/PEG-400 as an efficient catalytic system for preparation of α,β-unsaturated ketones (chalcones). The method presents one or more advantages over existing methodologies such as shorter reaction time, excellent yield, and low cost. All synthesized products were characterized by spectroscopic and analytical measurements.
Medicinal Chemistry Research, 2014
ABSTRACT Synthesis of novel thiophene substituted isoxazoline libraries is currently of high inte... more ABSTRACT Synthesis of novel thiophene substituted isoxazoline libraries is currently of high interest. Here, we have reported detailed syntheses of 2,5-dichlorothiophene, 5-chloro-2-(benzylthio)thiophene, and 5-chlorothiophene-2-sulphonamide substituted analogs of isoxazoline from chalcones catalyzed by NaOH in PEG-400 as green solvent. In vitro antimycobacterial and antimicrobial activity of newly synthesized compounds were investigated. Compounds 2j, 2k, and 2l showed excellent activity against Mycobacterium tuberculosis and other Mycobacterium strains tested. Compounds 2a–2c, 2i showed excellent activity against all bacterial and fungal species tested. The isoxazoline scaffold synthesized in the present study may be useful in the development of novel new antimicrobial agents. Graphical abstract An efficient synthesis of isoxazoline libraries of thiophene analogs and its antimycobacterial investigation.
Medicinal Chemistry Research, 2013
In the present communication, a simple and efficient synthesis of some new Pyrano-[2,3-c]-pyrazol... more In the present communication, a simple and efficient synthesis of some new Pyrano-[2,3-c]-pyrazoles derivatives are described by the one-pot condensation of a mixture of 3-methyl-1-phenyl-1H-pyrazole-5(4H)-one, substituted heterylaldehydes and malononitriles in polyethylene glycol (PEG-400) as green reaction solvent, further reacted with substituted acetophenones in the presence of polyethylene glycol (PEG-400) to form naphthalene analogues. Synthesis of novel substituted naphthalene analogues libraries are currently of high interest. The chemical structures of newly synthesized compounds were confirmed by IR, 1 H NMR and Mass spectral analysis. In vitro antimycobacterial activities of newly synthesized compounds were investigated against Mycobacterium smegmatis, Mycobacterium pheli and Mycobacterium tuberculosis species. The result revealed that most of the compounds showed good to moderate Antimycobacterial activity.
Journal of Heterocyclic Chemistry, 2009
magnified imagePoly(ethylene glycol) (PEG‐400) has been used as sustainable, nonvolatile, and env... more magnified imagePoly(ethylene glycol) (PEG‐400) has been used as sustainable, nonvolatile, and environmental friendly reaction solvent for the synthesis of title compounds. Various diaryl pyrido[3,2‐c]coumarins have been synthesized in one step by reacting 4‐hydroxy‐7‐methyl‐coumarin with α,β‐unsaturated ketones in the presence of ammonium acetate. Further, in vitro antimicrobial (antibacterial and antifungal) activities of the compounds were screened against different pathogens. The results revealed that most of them showed potent activity. J. Heterocyclic Chem., (2010).
Journal of Enzyme Inhibition and Medicinal Chemistry, 2008
Xanthine dehydrogenase (XDH) is responsible for the pathological condition called Gout. In the pr... more Xanthine dehydrogenase (XDH) is responsible for the pathological condition called Gout. In the present study different flavones synthesized from chalcone were evaluated in vitro for their inhibitory activity. Inhibitory activity of flavones on XDH was determined in terms of inhibition of uric acid synthesis from Xanthine. The enzymatic activity was found maximum at pH 7.5 and temperature 408C. The flavones 6-chloro-2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F 1) and 6-chloro-7methyl-2-[3-(4-chloro-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one(F 2),were noncompetitive and competitive inhibitor with Ki values 1.1 and 0.22 respectively. The flavones (F 1), (F 2), 6-chloro-2-[3-(4-chloro-phenyl)-1phenyl-1-Hpyrazol-4-yl]-chromen-4-one(F 3), 8-bromo-6-chloro-2-[3-(4-chloro-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F 4), 2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F 5) and 6-methyl-2-[3-(4-hydroxy-phenyl)-1-phenyl-1-H-pyrazol-4-yl]-chromen-4-one (F 6) were also screened for their antimicrobial activity, measured in terms of zone of inhibition. A broad spectrum antifungal activity was obtained against Trichoderma viridae, Candida albicans, Microsporum cannis, Penicillium chrysogenum and Fusarium moniliformae. In case of Aspergillus niger and Aspergillus flavous only spore formation was affected, while antibacterial activity was observed against Staphylococcus aureus, Bacillus subtilis and Serratia marsecens only. The flavones were further analyzed for quantitative structural activity relationship study (QSAR) by using PASS, online software to determine their Pa value. Toxicity and drug relevant properties were revealed by PALLAS software in terms of their molecular weight. Log P values were also studied. The result showed both the F 1 and F 2 flavones as antigout and therefore supports the development of novel drugs for the treatment of gout.
Green Chemistry Letters and Reviews, 2010
An efficient and convenient procedure for the synthesis of thiazole derivatives from α-haloketone... more An efficient and convenient procedure for the synthesis of thiazole derivatives from α-haloketone, thiourea and substituted acetophenones using polyethylene glycol-400 as a green and recyclable solvent is described. Significant rate enhancement and improved yields have been observed.