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Nigam P Rath - One of the best experts on this subject based on the ideXlab platform.
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synthesis and biological evaluation of a phosphonate analog of the natural acetyl cholinesterase inhibitor cyclophostin
Journal of Organic Chemistry, 2008Co-Authors: Saibal Bandyopadhyay, Supratik Dutta, Christopher D Spilling, Cynthia M Dupureur, Nigam P RathAbstract:Two diastereomers of a phosphonate analog 6 of the AChE inhibitor cyclophostin were synthesized. The substitution reaction of phosphono allylic carbonate 10a with methyl acetoacetate gave the vinyl phosphonate 9a. Attempted hydrogenation/debenzylation gave an unexpected enolether lactone. Alternatively, selective hydrogenation, demethylation, cyclization and debenzylation gave the phosphonate analog of cyclophostin as a separable mixture of diastereomers 6. The trans phosphonate Isomer was more active than Cis Isomer against AChE from two sources.
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synthesis and biological evaluation of a phosphonate analog of the natural acetyl cholinesterase inhibitor cyclophostin
Journal of Organic Chemistry, 2008Co-Authors: Saibal Bandyopadhyay, Supratik Dutta, Christopher D Spilling, Cynthia M Dupureur, Nigam P RathAbstract:Two diastereomers of a phosphonate analog 6 of the AChE inhibitor cyclophostin were synthesized. The substitution reaction of phosphono allylic carbonate 10a with methyl acetoacetate gave the vinyl phosphonate 9a. Attempted hydrogenation/debenzylation gave an unexpected enolether lactone. Alternatively, selective hydrogenation, demethylation, cyclization and debenzylation gave the phosphonate analog of cyclophostin as a separable mixture of diastereomers 6. The trans phosphonate Isomer was more active than the Cis Isomer against AChE from two sources.
Steven J Schwartz - One of the best experts on this subject based on the ideXlab platform.
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lycopene from heat induced Cis Isomer rich tomato sauce is more bioavailable than from all trans rich tomato sauce in human subjects
British Journal of Nutrition, 2007Co-Authors: Nuray Z Unlu, Steven K Clinton, David M Francis, Torsten Bohn, H N Nagaraja, Steven J SchwartzAbstract:Lycopene is present mainly as Cis-Isomers in human serum and tissues whereas all-trans-lycopene predominates in tomato products, suggesting that all-trans-lycopene is Isomerised in the body or is less bioavailable. The objectives of the present study were to develop processing conditions for tomatoes to obtain products with different Cis-trans-lycopene Isomer distribution and to assess their bioavailability. Healthy adult subjects (n 12) were recruited for this randomised cross-over trial. Each intervention was preceded by a 2-week washout period. Two tomato sauces, one rich in all-trans-lycopene (32·5 mg total lycopene/100 g sauce; 5 % Cis-Isomers), the other high in Cis-lycopene (26·4 mg total lycopene/100 g sauce; 45 % Cis-Isomers), were produced by different heat-processing techniques. Each sauce (150 g) was served in a standardised meal at 08.00 hours after overnight fasting. Plasma TAG-rich lipoprotein fractions over 9.5 h following test-meal consumption as a measure of lycopene absorption were obtained and expressed as baseline-corrected area under the concentration v. time curves (AUC), using HPLC-electrochemical detection. AUC values adjusted for the amount lycopene consumed showed that total, total Cis-, and all-trans-lycopene responses were significantly higher from the Cis-Isomer-rich sauce, compared with the all-trans-rich sauce, being 7·30 (SEM 1·45) v. 4·74 (SEM 1·08) nmol £ h/l (P¼0·002), 3·80 (SEM 0·76) v. 1·98 (SEM 0·37) nmol £ h/l (P¼ 0·0005) and 3·50 (SEM 0·76) v. 2·76 (SEM 0·76) nmol £ h/l (P¼0·01), respectively. The present study demonstrates significant lycopene bioavailability from Cis-lycopene-rich tomato sauce and highlights the importance of considering Isomer-distribution for lycopene bioavailability. Furthermore, processing parameters can be controlled to alter Isomer patterns of tomato products and influence lycopene bioavailability. Cis- and trans-lycopene: Heat processing: Postprandial absorption: Plasma triacylglycerol-rich lipoprotein fraction
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lycopene from heat induced Cis Isomer rich tomato sauce is more bioavailable than from all trans rich tomato sauce in human subjects
British Journal of Nutrition, 2007Co-Authors: Nuray Z Unlu, Steven K Clinton, David M Francis, Torsten Bohn, H N Nagaraja, Steven J SchwartzAbstract:Lycopene is present mainly as Cis-Isomers in human serum and tissues whereas all-trans-lycopene predominates in tomato products, suggesting that all-trans-lycopene is Isomerised in the body or is less bioavailable. The objectives of the present study were to develop processing conditions for tomatoes to obtain products with different Cis-trans-lycopene Isomer distribution and to assess their bioavailability. Healthy adult subjects (n 12) were recruited for this randomised cross-over trial. Each intervention was preceded by a 2-week washout period. Two tomato sauces, one rich in all-trans-lycopene (32.5 mg total lycopene/100 g sauce; 5 % Cis-Isomers), the other high in Cis-lycopene (26.4 mg total lycopene/100 g sauce; 45 % Cis-Isomers), were produced by different heat-processing techniques. Each sauce (150 g) was served in a standardised meal at 08.00 hours after overnight fasting. Plasma TAG-rich lipoprotein fractions over 9.5 h following test-meal consumption as a measure of lycopene absorption were obtained and expressed as baseline-corrected area under the concentration v. time curves (AUC), using HPLC-electrochemical detection. AUC values adjusted for the amount lycopene consumed showed that total, total Cis-, and all-trans-lycopene responses were significantly higher from the Cis-Isomer-rich sauce, compared with the all-trans-rich sauce, being 7.30 (sem 1.45) v. 4.74 (sem 1.08) nmol x h/l (P = 0.002), 3.80 (sem 0.76) v. 1.98 (sem 0.37) nmol x h/l (P = 0.0005) and 3.50 (sem 0.76) v. 2.76 (sem 0.76) nmol x h/l (P = 0.01), respectively. The present study demonstrates significant lycopene bioavailability from Cis-lycopene-rich tomato sauce and highlights the importance of considering Isomer-distribution for lycopene bioavailability. Furthermore, processing parameters can be controlled to alter Isomer patterns of tomato products and influence lycopene bioavailability.
Saibal Bandyopadhyay - One of the best experts on this subject based on the ideXlab platform.
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synthesis and biological evaluation of a phosphonate analog of the natural acetyl cholinesterase inhibitor cyclophostin
Journal of Organic Chemistry, 2008Co-Authors: Saibal Bandyopadhyay, Supratik Dutta, Christopher D Spilling, Cynthia M Dupureur, Nigam P RathAbstract:Two diastereomers of a phosphonate analog 6 of the AChE inhibitor cyclophostin were synthesized. The substitution reaction of phosphono allylic carbonate 10a with methyl acetoacetate gave the vinyl phosphonate 9a. Attempted hydrogenation/debenzylation gave an unexpected enolether lactone. Alternatively, selective hydrogenation, demethylation, cyclization and debenzylation gave the phosphonate analog of cyclophostin as a separable mixture of diastereomers 6. The trans phosphonate Isomer was more active than Cis Isomer against AChE from two sources.
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synthesis and biological evaluation of a phosphonate analog of the natural acetyl cholinesterase inhibitor cyclophostin
Journal of Organic Chemistry, 2008Co-Authors: Saibal Bandyopadhyay, Supratik Dutta, Christopher D Spilling, Cynthia M Dupureur, Nigam P RathAbstract:Two diastereomers of a phosphonate analog 6 of the AChE inhibitor cyclophostin were synthesized. The substitution reaction of phosphono allylic carbonate 10a with methyl acetoacetate gave the vinyl phosphonate 9a. Attempted hydrogenation/debenzylation gave an unexpected enolether lactone. Alternatively, selective hydrogenation, demethylation, cyclization and debenzylation gave the phosphonate analog of cyclophostin as a separable mixture of diastereomers 6. The trans phosphonate Isomer was more active than the Cis Isomer against AChE from two sources.
Nuray Z Unlu - One of the best experts on this subject based on the ideXlab platform.
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lycopene from heat induced Cis Isomer rich tomato sauce is more bioavailable than from all trans rich tomato sauce in human subjects
British Journal of Nutrition, 2007Co-Authors: Nuray Z Unlu, Steven K Clinton, David M Francis, Torsten Bohn, H N Nagaraja, Steven J SchwartzAbstract:Lycopene is present mainly as Cis-Isomers in human serum and tissues whereas all-trans-lycopene predominates in tomato products, suggesting that all-trans-lycopene is Isomerised in the body or is less bioavailable. The objectives of the present study were to develop processing conditions for tomatoes to obtain products with different Cis-trans-lycopene Isomer distribution and to assess their bioavailability. Healthy adult subjects (n 12) were recruited for this randomised cross-over trial. Each intervention was preceded by a 2-week washout period. Two tomato sauces, one rich in all-trans-lycopene (32·5 mg total lycopene/100 g sauce; 5 % Cis-Isomers), the other high in Cis-lycopene (26·4 mg total lycopene/100 g sauce; 45 % Cis-Isomers), were produced by different heat-processing techniques. Each sauce (150 g) was served in a standardised meal at 08.00 hours after overnight fasting. Plasma TAG-rich lipoprotein fractions over 9.5 h following test-meal consumption as a measure of lycopene absorption were obtained and expressed as baseline-corrected area under the concentration v. time curves (AUC), using HPLC-electrochemical detection. AUC values adjusted for the amount lycopene consumed showed that total, total Cis-, and all-trans-lycopene responses were significantly higher from the Cis-Isomer-rich sauce, compared with the all-trans-rich sauce, being 7·30 (SEM 1·45) v. 4·74 (SEM 1·08) nmol £ h/l (P¼0·002), 3·80 (SEM 0·76) v. 1·98 (SEM 0·37) nmol £ h/l (P¼ 0·0005) and 3·50 (SEM 0·76) v. 2·76 (SEM 0·76) nmol £ h/l (P¼0·01), respectively. The present study demonstrates significant lycopene bioavailability from Cis-lycopene-rich tomato sauce and highlights the importance of considering Isomer-distribution for lycopene bioavailability. Furthermore, processing parameters can be controlled to alter Isomer patterns of tomato products and influence lycopene bioavailability. Cis- and trans-lycopene: Heat processing: Postprandial absorption: Plasma triacylglycerol-rich lipoprotein fraction
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lycopene from heat induced Cis Isomer rich tomato sauce is more bioavailable than from all trans rich tomato sauce in human subjects
British Journal of Nutrition, 2007Co-Authors: Nuray Z Unlu, Steven K Clinton, David M Francis, Torsten Bohn, H N Nagaraja, Steven J SchwartzAbstract:Lycopene is present mainly as Cis-Isomers in human serum and tissues whereas all-trans-lycopene predominates in tomato products, suggesting that all-trans-lycopene is Isomerised in the body or is less bioavailable. The objectives of the present study were to develop processing conditions for tomatoes to obtain products with different Cis-trans-lycopene Isomer distribution and to assess their bioavailability. Healthy adult subjects (n 12) were recruited for this randomised cross-over trial. Each intervention was preceded by a 2-week washout period. Two tomato sauces, one rich in all-trans-lycopene (32.5 mg total lycopene/100 g sauce; 5 % Cis-Isomers), the other high in Cis-lycopene (26.4 mg total lycopene/100 g sauce; 45 % Cis-Isomers), were produced by different heat-processing techniques. Each sauce (150 g) was served in a standardised meal at 08.00 hours after overnight fasting. Plasma TAG-rich lipoprotein fractions over 9.5 h following test-meal consumption as a measure of lycopene absorption were obtained and expressed as baseline-corrected area under the concentration v. time curves (AUC), using HPLC-electrochemical detection. AUC values adjusted for the amount lycopene consumed showed that total, total Cis-, and all-trans-lycopene responses were significantly higher from the Cis-Isomer-rich sauce, compared with the all-trans-rich sauce, being 7.30 (sem 1.45) v. 4.74 (sem 1.08) nmol x h/l (P = 0.002), 3.80 (sem 0.76) v. 1.98 (sem 0.37) nmol x h/l (P = 0.0005) and 3.50 (sem 0.76) v. 2.76 (sem 0.76) nmol x h/l (P = 0.01), respectively. The present study demonstrates significant lycopene bioavailability from Cis-lycopene-rich tomato sauce and highlights the importance of considering Isomer-distribution for lycopene bioavailability. Furthermore, processing parameters can be controlled to alter Isomer patterns of tomato products and influence lycopene bioavailability.
Mehdi Rashidi - One of the best experts on this subject based on the ideXlab platform.
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Oxidative Addition of Propargyl Halides, Chloroacetonitrile, and Ethyl Chloroacetate to a Dimethylplatinum(II) Complex: Kinetic and DFT Studies
Organometallics, 2014Co-Authors: S. Jafar Hoseini, Hasan Nasrabadi, Zohreh Moradi, Roghayeh Hashemi Fath, Mehdi RashidiAbstract:Oxidative addition reaction of propargyl halides, XCH2C≡CH (X = Cl, Br), with the platinum(II) complex [PtMe2(bipy)] (1), in which bipy = 2,2′-bipyridine, gave a mixture of the propargyl halide complex [PtXMe2(CH2C≡CH)(bipy)], (X = Cl, trans Isomer 2a and Cis Isomer 2a′; X = Br, trans Isomer 2b and Cis Isomer 2b′) and the allene complex [PtXMe2(CH═C═CH2)(bipy)], (X = Cl, trans Isomer 3a and Cis Isomer 3a′; X = Br, trans Isomer 3b and Cis Isomer 3b′). The reaction involving propargyl bromide followed second-order kinetics (first order in both reactants), while that involving propargyl chloride showed third-order kinetics (first order in 1, second order in ClCH2C≡CH) in acetone or benzene solvent. Similar reactions of chloroacetonitrile (ClCH2C≡N) and ethyl chloroacetate (ClCH2COOEt) reagents with complex 1 yielded [PtClMe2(CH2C≡N)(bipy)] (4) and [PtClMe2(CH2COOEt)(bipy)] (5), respectively, each as a mixture of Cis and trans Isomers, proceeding with second-order kinetics. Unpredictably, the reaction rates o...
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Oxidative Addition of Propargyl Halides, Chloroacetonitrile, and Ethyl Chloroacetate to a Dimethylplatinum(II) Complex: Kinetic and DFT Studies
2014Co-Authors: Jafar S. Hoseini, Hasan Nasrabadi, Roghayeh Hashemi Fath, Zohreh Moradi, Mehdi RashidiAbstract:Oxidative addition reaction of propargyl halides, XCH2CCH (X = Cl, Br), with the platinum(II) complex [PtMe2(bipy)] (1), in which bipy = 2,2′-bipyridine, gave a mixture of the propargyl halide complex [PtXMe2(CH2CCH)(bipy)], (X = Cl, trans Isomer 2a and Cis Isomer 2a′; X = Br, trans Isomer 2b and Cis Isomer 2b′) and the allene complex [PtXMe2(CHCCH2)(bipy)], (X = Cl, trans Isomer 3a and Cis Isomer 3a′; X = Br, trans Isomer 3b and Cis Isomer 3b′). The reaction involving propargyl bromide followed second-order kinetics (first order in both reactants), while that involving propargyl chloride showed third-order kinetics (first order in 1, second order in ClCH2CCH) in acetone or benzene solvent. Similar reactions of chloroacetonitrile (ClCH2CN) and ethyl chloroacetate (ClCH2COOEt) reagents with complex 1 yielded [PtClMe2(CH2CN)(bipy)] (4) and [PtClMe2(CH2COOEt)(bipy)] (5), respectively, each as a mixture of Cis and trans Isomers, proceeding with second-order kinetics. Unpredictably, the reaction rates of complex 1 with propargyl bromide and chloroacetonitrile in benzene solvent are faster than those in acetone solvent. Consistent with our 1H NMR experimental results, DFT studies showed that the Cis addition products of allene tautomers (3a′,b′) are more stable than their corresponding trans Isomers (3a,b)