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Kajal Chakraborty - One of the best experts on this subject based on the ideXlab platform.
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first report of two new antioxidative meroterpeno 2h pyranoids from short necked yellow foot clam paphia malabarica family veneridae with bioactivity against pro inflammatory cyclooxygenases and lipoxygenase
Natural Product Research, 2017Co-Authors: Minju Joy, Kajal ChakrabortyAbstract:AbstractTwo new meroterpeno 2H-pyranoids were isolated from the EtOAc:MeOH extract of yellow-foot clam Paphia malabarica. The structures of these newly reported compounds were elucidated based on spectroscopic interpretations. This is the first report of biogenic 2H-pyrans bearing decadienyl and allyloxy-(isopentanyl)-cyclohexene skeletons from marine biota. The extended C18 sesquiterpenoid with prenylated irregular farnesene framework was characterised as 2-((E)-deca-1,8-dien-10-yl)-11,12-dihydro-13-propyl-2H-pyran (1). The compound 2, 1′-((10E)-10-(10-(pentan-4-yl)-cyclohex-4-enyl)-allyloxy)-tetrahydro-2′,2′-dimethyl-2H-pyran represents the first example of naturally occurring C21 prenylated bisabolene-type meroterpenoid, whereas tetrahydro-2′,2′-dimethyl-2H-pyran remains attached at C-2′ position of rearranged bisabolene framework formed by allyloxy linkage. The antioxidant activities (DPPH/ABTS+) of 1 and 2 were comparable (IC50 < 1.0 mg/mL) with α-tocopherol. In addition, these compounds exhibited gr...
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First report of two new antioxidative meroterpeno 2H-pyranoids from short-necked yellow-foot clam Paphia malabarica (family: Veneridae) with bioactivity against pro-inflammatory cyclooxygenases and lipoxygenase
2016Co-Authors: Minju Joy, Kajal ChakrabortyAbstract:Two new meroterpeno 2H-pyranoids were isolated from the EtOAc:MeOH extract of yellow-foot clam Paphia malabarica. The structures of these newly reported compounds were elucidated based on spectroscopic interpretations. This is the first report of biogenic 2H-pyrans bearing decadienyl and allyloxy-(isopentanyl)-cyclohexene skeletons from marine biota. The extended C18 sesquiterpenoid with prenylated irregular farnesene framework was characterised as 2-((E)-deca-1,8-dien-10-yl)-11,12-dihydro-13-propyl-2H-pyran (1). The compound 2, 1′-((10E)-10-(10-(pentan-4-yl)-cyclohex-4-enyl)-allyloxy)-tetrahydro-2′,2′-dimethyl-2H-pyran represents the first example of naturally occurring C21 prenylated bisabolene-type meroterpenoid, whereas tetrahydro-2′,2′-dimethyl-2H-pyran remains attached at C-2′ position of rearranged bisabolene framework formed by allyloxy linkage. The antioxidant activities (DPPH/ABTS+) of 1 and 2 were comparable (IC50
Minju Joy - One of the best experts on this subject based on the ideXlab platform.
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first report of two new antioxidative meroterpeno 2h pyranoids from short necked yellow foot clam paphia malabarica family veneridae with bioactivity against pro inflammatory cyclooxygenases and lipoxygenase
Natural Product Research, 2017Co-Authors: Minju Joy, Kajal ChakrabortyAbstract:AbstractTwo new meroterpeno 2H-pyranoids were isolated from the EtOAc:MeOH extract of yellow-foot clam Paphia malabarica. The structures of these newly reported compounds were elucidated based on spectroscopic interpretations. This is the first report of biogenic 2H-pyrans bearing decadienyl and allyloxy-(isopentanyl)-cyclohexene skeletons from marine biota. The extended C18 sesquiterpenoid with prenylated irregular farnesene framework was characterised as 2-((E)-deca-1,8-dien-10-yl)-11,12-dihydro-13-propyl-2H-pyran (1). The compound 2, 1′-((10E)-10-(10-(pentan-4-yl)-cyclohex-4-enyl)-allyloxy)-tetrahydro-2′,2′-dimethyl-2H-pyran represents the first example of naturally occurring C21 prenylated bisabolene-type meroterpenoid, whereas tetrahydro-2′,2′-dimethyl-2H-pyran remains attached at C-2′ position of rearranged bisabolene framework formed by allyloxy linkage. The antioxidant activities (DPPH/ABTS+) of 1 and 2 were comparable (IC50 < 1.0 mg/mL) with α-tocopherol. In addition, these compounds exhibited gr...
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First report of two new antioxidative meroterpeno 2H-pyranoids from short-necked yellow-foot clam Paphia malabarica (family: Veneridae) with bioactivity against pro-inflammatory cyclooxygenases and lipoxygenase
2016Co-Authors: Minju Joy, Kajal ChakrabortyAbstract:Two new meroterpeno 2H-pyranoids were isolated from the EtOAc:MeOH extract of yellow-foot clam Paphia malabarica. The structures of these newly reported compounds were elucidated based on spectroscopic interpretations. This is the first report of biogenic 2H-pyrans bearing decadienyl and allyloxy-(isopentanyl)-cyclohexene skeletons from marine biota. The extended C18 sesquiterpenoid with prenylated irregular farnesene framework was characterised as 2-((E)-deca-1,8-dien-10-yl)-11,12-dihydro-13-propyl-2H-pyran (1). The compound 2, 1′-((10E)-10-(10-(pentan-4-yl)-cyclohex-4-enyl)-allyloxy)-tetrahydro-2′,2′-dimethyl-2H-pyran represents the first example of naturally occurring C21 prenylated bisabolene-type meroterpenoid, whereas tetrahydro-2′,2′-dimethyl-2H-pyran remains attached at C-2′ position of rearranged bisabolene framework formed by allyloxy linkage. The antioxidant activities (DPPH/ABTS+) of 1 and 2 were comparable (IC50
Jyothi Madda - One of the best experts on this subject based on the ideXlab platform.
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synthesis of novel chromeno annulated cis fused pyrano 3 4 c benzopyran and naphtho pyran derivatives via domino aldol type hetero diels alder reaction and their cytotoxicity evaluation
Bioorganic & Medicinal Chemistry Letters, 2014Co-Authors: Jyothi Madda, Akkaladevi Venkatesham, Ganesh C Kumar, Bejjanki Naveen Kumar, K Nagaiah, Pombala Sujitha, Tadikamalla Prabhakar Rao, Nanubolu Jagadeesh BabuAbstract:Abstract New chromeno-annulated cis-fused pyrano[3,4-c]benzopyran and naphtho pyran derivatives have been synthesized by domino aldol-type reaction/hetero Diels–Alder reaction generated from o-quinone methide in situ from 7-O-prenyl derivatives of 8-formyl-2,3-disubstituted chromenones with resorcinols/naphthols in the presence of 20 mol % ethylenediamine diacetate (EDDA), triethylamine (2 mL) as co-catalyst in CH3CN under reflux conditions in good yields. The structures were established based on spectroscopic data, and further confirmed by X-ray diffraction analysis. The results showed that compounds 4h and 4j exhibited very potent cytotoxicity against human cervical cancer cell line (HeLa). Compound 4h displayed good inhibitory activity against both breast cancer cell lines, MDA-MB-231 and MCF-7. Further, the compound 4i exhibited good cytotoxicity against only MDA-MB-231, and compound 4j showed promising activity against human lung cancer cell line, A549 with IC50 value of 2.53 ± 0.07 μM, which was comparable to the standard doxorubicin (IC50 = 1.21 ± 0.1 μM).
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synthesis of new chromeno annulated cis fused pyrano 4 3 c isoxazole derivatives via intramolecular nitrone cycloaddition and their cytotoxicity evaluation
Bioorganic & Medicinal Chemistry Letters, 2013Co-Authors: Naveen Kumar Bejjanki, Akkaladevi Venkatesham, Jyothi Madda, Nagaiah Kommu, Sujitha Pombala, Ganesh C Kumar, Kothakonda Rajendra Prasad, Jagadeesh Babu NanuboluAbstract:Abstract New cis-fused chromeno pyrano[4,3-c]isoxazole derivatives have been synthesized by intramolecular [1,3]-cycloaddition of the nitrones generated in situ from hydroxylamine derivatives and 7-O-prenyl derivatives of 8-formyl-2,3-disubstituted chromenones using PEG-400 as a reaction medium under catalyst-free conditions good to excellent yields. The structures were established by spectroscopic data and further confirmed by X-ray diffraction analysis. The results showed that compounds 4b, 4c, 4d, 4e and 4k exhibit very potent antiproliferative activity against MDA-MB-231 breast cancer cells. Compounds 4a, 4c, 4e, 4i and 4k displayed potent inhibitory activity against human MCF-7 breast cancer cell lines. Compounds 4h and 4i exhibited significant anti-proliferative activity against human cervical cancer cell line, HeLa. While 4b, 4d and 4j were active against human lung cancer cell line, A549. In addition, Compound 4j was found to be the most promising against A549 (Lung cancer) with IC50 value of 0.194 μM.
Nanubolu Jagadeesh Babu - One of the best experts on this subject based on the ideXlab platform.
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synthesis of novel chromeno annulated cis fused pyrano 3 4 c benzopyran and naphtho pyran derivatives via domino aldol type hetero diels alder reaction and their cytotoxicity evaluation
Bioorganic & Medicinal Chemistry Letters, 2014Co-Authors: Jyothi Madda, Akkaladevi Venkatesham, Ganesh C Kumar, Bejjanki Naveen Kumar, K Nagaiah, Pombala Sujitha, Tadikamalla Prabhakar Rao, Nanubolu Jagadeesh BabuAbstract:Abstract New chromeno-annulated cis-fused pyrano[3,4-c]benzopyran and naphtho pyran derivatives have been synthesized by domino aldol-type reaction/hetero Diels–Alder reaction generated from o-quinone methide in situ from 7-O-prenyl derivatives of 8-formyl-2,3-disubstituted chromenones with resorcinols/naphthols in the presence of 20 mol % ethylenediamine diacetate (EDDA), triethylamine (2 mL) as co-catalyst in CH3CN under reflux conditions in good yields. The structures were established based on spectroscopic data, and further confirmed by X-ray diffraction analysis. The results showed that compounds 4h and 4j exhibited very potent cytotoxicity against human cervical cancer cell line (HeLa). Compound 4h displayed good inhibitory activity against both breast cancer cell lines, MDA-MB-231 and MCF-7. Further, the compound 4i exhibited good cytotoxicity against only MDA-MB-231, and compound 4j showed promising activity against human lung cancer cell line, A549 with IC50 value of 2.53 ± 0.07 μM, which was comparable to the standard doxorubicin (IC50 = 1.21 ± 0.1 μM).
Bubun Banerjee - One of the best experts on this subject based on the ideXlab platform.
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eco friendly one pot multicomponent synthesis of pyran annulated heterocyclic scaffolds at room temperature using ammonium or sodium formate as non toxic catalyst
Journal of Heterocyclic Chemistry, 2014Co-Authors: Goutam Brahmachari, Sujay Laskar, Bubun BanerjeeAbstract:A simple, facile, and convenient practical method for one-pot synthesis of pharmaceutically interesting diverse kind of pyran annulated heterocycles such as 4H-Pyrano[3,2-c]coumarins, 4H-Pyrano[3,2-c]-α-pyrones, 5,6,7,8-tetrahydro-5-oxo-4H-chromenes and benzo[h]-4H-chromenes in the presence of ammonium or sodium formate as catalyst via three-component condensation reaction of aromatic aldehydes, malononitrile, and C−H activated acidic compounds in aqueous ethanol has been developed mostly at room temperature. The salient features of the present method are mild reaction conditions, good to excellent yields, high atom economy, environmentally benign, easy isolation of products, no column chromatographic separation and reusability of reaction media.
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facile and one pot access to diverse and densely functionalized 2 amino 3 cyano 4h pyrans and pyran annulated heterocyclic scaffolds via an eco friendly multicomponent reaction at room temperature using urea as a novel organo catalyst
ACS Sustainable Chemistry & Engineering, 2014Co-Authors: Goutam Brahmachari, Bubun BanerjeeAbstract:A simple, straightforward, and highly efficient multicomponent one-pot synthesis of a pharmaceutically interesting diverse kind of functionalized 2-amino-3-cyano-4H-Pyrans and pyran-annulated heterocycles has been developed based on a low-cost and environmentally benign commercially available urea as a novel organo-catalyst. The reaction occurs via tandem Knoevenagel–cyclocondensation of aldehydes, malononitrile, and C–H-activated acidic compounds in aqueous ethanol at room temperature. Following this protocol, it was possible to synthesize 2-amino-3-cyano-pyrano[3,2-c]chromen-5(4H)-ones (4aa–4al), 2-amino-3-cyano-pyrano[4,3-b]pyran-5(4H)-ones (4ba–4be), 2-amino-3-cyano-7,8-dihydro-4H-chromen-5(6H)-one (4ca–4cr), 1H-pyrano[2,3-d]pyrimidine-2,4(3H,5H)-diones (4da–4dd), 2-amino-3-cyano-5,10-dioxo-5,10-dihydro-4H-benzo[g]chromenes (4ea–4ec), 2-amino-3-cyano-4H-Pyrans (4fa–4fh), and 1,4-dihydropyrano[2,3-c]pyrazoles (4ga–4gb). The salient features of the present protocol are mild reaction conditions, excellen...
