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Derek R Boyd - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of benzo[g]chrysene, benzo[g]chrysene 9,10-Oxide and benzo[g]chrysene 1,2 : 9,10-diOxide
Journal of The Chemical Society-perkin Transactions 1, 2016Co-Authors: Shiv K. Agarwal, Derek R Boyd, W. Brian JenningsAbstract:Benzo[g]chrysene has been synthesised and used in the preparation of the K-region Arene Oxide, benzo[g]chrysene 9,10-Oxide. Attempts to synthesise the fjord region Arene Oxide, benzo[g]chrysene 1,2-Oxide, were unsuccessful but a fjord region diArene Oxide, benzo[g]chrysene 1,2 : 9,10-diOxide has been obtained.
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Synthesis and thermal racemization of the predominant Arene Oxide metabolite of chrysene, (+)-(3S,4R)-chrysene 3,4-Oxide
Journal of The Chemical Society-perkin Transactions 1, 2016Co-Authors: Derek R Boyd, Michael G. Burnett, Ruth M. E. GreeneAbstract:(–)-trans-4-Bromo-3-hydroxy-1,2,3,4-tetrahydrochrysene has been obtained from the chromatographic separation and cleavage of the corresponding menthyloxyacetyl (MOA) diastereoisomer. The (–)-enantiomer of this bromohydrin has been assigned (3R,4R)absolute stereochemistry and used in the synthesis of (+)-(3S,4R)-chrysene 3,4-Oxide. Thermal racemization studies on this Arene Oxide gave a barrier to racemization (Ea) of 25.15 kcal mol–1 and an activation entropy (ΔS‡) of 0.7 cal mol–1 K–1, in accord with PMO predictions.
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biphenyl dioxygenase catalysed cis dihydroxylation of tricyclic azaArenes chemoenzymatic synthesis of Arene Oxide metabolites and furoquinoline alkaloids
RSC Advances, 2013Co-Authors: Derek R Boyd, Narain D Sharma, Jonathan G Carroll, Pui L Loke, Colin Odowd, Christopher C R AllenAbstract:Biotransformation of acridine, dictamnine and 4-chlorofuro[2,3-b]quinolone, using whole cells of Sphingomonas yanoikuyae B8/36, yielded five enantiopure cyclic cis-dihydrodiols, from biphenyl dioxygenase-catalysed dihydroxylation of the carbocyclic rings. cis-Dihydroxylation of the furan ring in dictamnine and 4-chlorofuro[2,3-b]quinoline, followed by ring opening and reduction, yielded two exocyclic diols. The structures and absolute configurations of metabolites have been determined by spectroscopy and stereochemical correlation methods. Enantiopure Arene Oxide metabolites of acridine and dictamnine have been synthesised, from the corresponding cis-dihydrodiols. The achiral furoquinoline alkaloids robustine, γ-fagarine, haplopine, isohaplopine-3,3′-dimethylallylether and pteleine have been obtained, from either cis-dihydrodiol, catechol or Arene Oxide metabolites of dictamnine.
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Chemoenzymatic synthesis of monocyclic Arene Oxides and Arene hydrates from substituted benzene substrates.
Organic and Biomolecular Chemistry, 2013Co-Authors: Derek R Boyd, Narain D Sharma, Vera Ljubez, Peter K. M. Mcgeehin, Paul J. Stevenson, Marine Blain, Christopher C R AllenAbstract:Enantiopure cis-dihydrodiol bacterial metabolites of substituted benzene substrates were used as precursors, in a chemoenzymatic synthesis of the corresponding benzene Oxides and of a substituted oxepine, via dihydrobenzene Oxide intermediates. A rapid total racemization of the substituted benzene 2,3-Oxides was found to have occurred, via their oxepine valence tautomers, in accord with predictions and theoretical calculations. Reduction of a substituted Arene Oxide to yield a racemic Arene hydrate was observed. Arene hydrates have also been synthesised, in enantiopure form, from the corresponding dihydroArene Oxide or trans-bromoacetate precursors. Biotransformation of one Arene hydrate enantiomer resulted in a toluene-dioxygenase catalysed cis-dihydroxylation to yield a benzene cis-triol metabolite.
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Enzyme-catalysed synthesis and reactions of benzene Oxide/oxepine derivatives of methyl benzoates
Organic and Biomolecular Chemistry, 2008Co-Authors: Derek R Boyd, Narain D Sharma, John F Malone, John S. Harrison, W. C. Mcroberts, John T. G. Hamilton, David B. HarperAbstract:A series of twelve benzoate esters was metabolised, by species of the Phellinus genus of wood-rotting fungi, to yield the corresponding benzyl alcohol derivatives and eight salicylates. The isolation of a stable oxepine metabolite, from methyl benzoate, allied to evidence of the migration and retention of a carbomethoxy group (the NIH Shift), during enzyme-catalysed ortho-hydroxylation of alkyl benzoates to form salicylates, is consistent with a mechanism involving an initial Arene epoxidation step. This mechanism was confirmed by the isolation of a remarkably stable, optically active, substituted benzene Oxide metabolite of methyl 2-(trifluoromethyl)benzoate, which slowly converted into the racemic form. The Arene Oxide was found to undergo a cycloaddition reaction with 4-phenyl-1,2,4-triazoline-3,5-dione to yield a crystalline cycloadduct whose structure and racemic nature was established by X-ray crystallography. The metabolite was also found to undergo some novel benzene Oxide reactions, including epoxidation to give an anti-diepOxide, base-catalysed hydrolysis to form a trans-dihydrodiol and acid-catalysed aromatisation to yield a salicylate derivative via the NIH Shift of a carbomethoxy group.
Ronald G Harvey - One of the best experts on this subject based on the ideXlab platform.
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Arene Oxide synthesis phenanthrene 9 10 Oxide
Organic Syntheses, 2003Co-Authors: Cecilia Cortez, Ronald G HarveyAbstract:Arene Oxide SYNTHESIS: PHENANTHRENE-9,10-Oxide intermediate: trans-9,10-Dihydro-9,10-phenanthrenediol (1) product: Phenanthrene-9,10-Oxide (2) Keywords: elimination, dehydration; epOxide formation; reduction, CO choh; 9,10-phenanthrenequinone; tetrahydrofuran
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Organic Syntheses - Arene Oxide Synthesis: Phenanthrene‐9,10‐Oxide
Organic Syntheses, 2003Co-Authors: Cecilia Cortez, Ronald G HarveyAbstract:Arene Oxide SYNTHESIS: PHENANTHRENE-9,10-Oxide intermediate: trans-9,10-Dihydro-9,10-phenanthrenediol (1) product: Phenanthrene-9,10-Oxide (2) Keywords: elimination, dehydration; epOxide formation; reduction, CO choh; 9,10-phenanthrenequinone; tetrahydrofuran
Narain D Sharma - One of the best experts on this subject based on the ideXlab platform.
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biphenyl dioxygenase catalysed cis dihydroxylation of tricyclic azaArenes chemoenzymatic synthesis of Arene Oxide metabolites and furoquinoline alkaloids
RSC Advances, 2013Co-Authors: Derek R Boyd, Narain D Sharma, Jonathan G Carroll, Pui L Loke, Colin Odowd, Christopher C R AllenAbstract:Biotransformation of acridine, dictamnine and 4-chlorofuro[2,3-b]quinolone, using whole cells of Sphingomonas yanoikuyae B8/36, yielded five enantiopure cyclic cis-dihydrodiols, from biphenyl dioxygenase-catalysed dihydroxylation of the carbocyclic rings. cis-Dihydroxylation of the furan ring in dictamnine and 4-chlorofuro[2,3-b]quinoline, followed by ring opening and reduction, yielded two exocyclic diols. The structures and absolute configurations of metabolites have been determined by spectroscopy and stereochemical correlation methods. Enantiopure Arene Oxide metabolites of acridine and dictamnine have been synthesised, from the corresponding cis-dihydrodiols. The achiral furoquinoline alkaloids robustine, γ-fagarine, haplopine, isohaplopine-3,3′-dimethylallylether and pteleine have been obtained, from either cis-dihydrodiol, catechol or Arene Oxide metabolites of dictamnine.
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Chemoenzymatic synthesis of monocyclic Arene Oxides and Arene hydrates from substituted benzene substrates.
Organic and Biomolecular Chemistry, 2013Co-Authors: Derek R Boyd, Narain D Sharma, Vera Ljubez, Peter K. M. Mcgeehin, Paul J. Stevenson, Marine Blain, Christopher C R AllenAbstract:Enantiopure cis-dihydrodiol bacterial metabolites of substituted benzene substrates were used as precursors, in a chemoenzymatic synthesis of the corresponding benzene Oxides and of a substituted oxepine, via dihydrobenzene Oxide intermediates. A rapid total racemization of the substituted benzene 2,3-Oxides was found to have occurred, via their oxepine valence tautomers, in accord with predictions and theoretical calculations. Reduction of a substituted Arene Oxide to yield a racemic Arene hydrate was observed. Arene hydrates have also been synthesised, in enantiopure form, from the corresponding dihydroArene Oxide or trans-bromoacetate precursors. Biotransformation of one Arene hydrate enantiomer resulted in a toluene-dioxygenase catalysed cis-dihydroxylation to yield a benzene cis-triol metabolite.
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Enzyme-catalysed synthesis and reactions of benzene Oxide/oxepine derivatives of methyl benzoates
Organic and Biomolecular Chemistry, 2008Co-Authors: Derek R Boyd, Narain D Sharma, John F Malone, John S. Harrison, W. C. Mcroberts, John T. G. Hamilton, David B. HarperAbstract:A series of twelve benzoate esters was metabolised, by species of the Phellinus genus of wood-rotting fungi, to yield the corresponding benzyl alcohol derivatives and eight salicylates. The isolation of a stable oxepine metabolite, from methyl benzoate, allied to evidence of the migration and retention of a carbomethoxy group (the NIH Shift), during enzyme-catalysed ortho-hydroxylation of alkyl benzoates to form salicylates, is consistent with a mechanism involving an initial Arene epoxidation step. This mechanism was confirmed by the isolation of a remarkably stable, optically active, substituted benzene Oxide metabolite of methyl 2-(trifluoromethyl)benzoate, which slowly converted into the racemic form. The Arene Oxide was found to undergo a cycloaddition reaction with 4-phenyl-1,2,4-triazoline-3,5-dione to yield a crystalline cycloadduct whose structure and racemic nature was established by X-ray crystallography. The metabolite was also found to undergo some novel benzene Oxide reactions, including epoxidation to give an anti-diepOxide, base-catalysed hydrolysis to form a trans-dihydrodiol and acid-catalysed aromatisation to yield a salicylate derivative via the NIH Shift of a carbomethoxy group.
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cis dihydrodiol Arene Oxide and phenol metabolites of dictamnine key intermediates in the biodegradation and biosynthesis of furoquinoline alkaloids
Chemical Communications, 2005Co-Authors: Derek R Boyd, Narain D Sharma, Jonathan G Carroll, Pui L Loke, Colin Odowd, Christopher C R AllenAbstract:Biotransformation of the parent furoquinoline alkaloid dictamnine and its 4-chlorofuroquinoline precursor, using the B8/36 bacterial mutant strain of Sphingomonas yanoikuyae, yielded, via biphenyl dioxygenase-catalysed dihydroxylation, the first isolable alkaloid cis-dihydrodiol metabolites; these metabolites were used in the chemoenzymatic synthesis of postulated Arene Oxide and phenol intermediates, and a range of derived furoquinoline alkaloids.
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synthesis and isomerization of Arene Oxide metabolites of phenanthrene triphenylene dibenz a c anthracene and dibenz a h anthracene
Journal of The Chemical Society-perkin Transactions 1, 2001Co-Authors: Suresh K Balani, Derek R Boyd, Narain D Sharma, Ian N Brannigan, Francis Hempenstall, Allison SmithAbstract:Dibenz[a,h]anthracene 3,4-Oxide 5ARS, synthesised from the enantiopure dibromoMTPA precursor 9ARRS*, was found to have totally racemized and to be accompanied by benz[5,6]anthra[1,2-b]oxepine 11A. Phenanthrene 3,4-Oxide 5BRS, obtained from the enantiopure bacterial metabolite cis-3,4-dihydroxy-3,4-dihydrophenanthrene 12B by a modified synthetic approach involving the chlorohydrin ester 16B, was observed to racemize spontaneously at ambient temperature. Dibenz[a,h]anthracene 3,4-Oxide 5ARS/5ASR, phenanthrene 3,4-Oxide 5BRS/5BSR, triphenylene 1,2-Oxide 5CRS/5CSR, and dibenz[a,c]anthracene 1,2-Oxide 5DRS/5DSR, obtained from the corresponding racemic cis-tetrahydrodiol precursors 14A–14D by the new method, were obtained without any evidence of the formation of benz[5,6]anthra[1,2-b]oxepine 11A, naphth[1,2-b]oxepine 11B, phenanthro[10,9-b]oxepine 11C, or benz[3,4]anthra[1,2-b]oxepine 11D isomers respectively. The total racemization of Arene Oxide 5ARS and formation of oxepine 11A from the bromoMTPA precursor 8ARRS* are in accord with earlier PMO predictions based on resonance energy considerations. Photoisomerization of Arene Oxides 5ARS/5ASR, 5CRS/5CSR, and 5DRS/5DSR was found to yield the corresponding oxepines 11A, 11C, and 11D.
Christopher C R Allen - One of the best experts on this subject based on the ideXlab platform.
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biphenyl dioxygenase catalysed cis dihydroxylation of tricyclic azaArenes chemoenzymatic synthesis of Arene Oxide metabolites and furoquinoline alkaloids
RSC Advances, 2013Co-Authors: Derek R Boyd, Narain D Sharma, Jonathan G Carroll, Pui L Loke, Colin Odowd, Christopher C R AllenAbstract:Biotransformation of acridine, dictamnine and 4-chlorofuro[2,3-b]quinolone, using whole cells of Sphingomonas yanoikuyae B8/36, yielded five enantiopure cyclic cis-dihydrodiols, from biphenyl dioxygenase-catalysed dihydroxylation of the carbocyclic rings. cis-Dihydroxylation of the furan ring in dictamnine and 4-chlorofuro[2,3-b]quinoline, followed by ring opening and reduction, yielded two exocyclic diols. The structures and absolute configurations of metabolites have been determined by spectroscopy and stereochemical correlation methods. Enantiopure Arene Oxide metabolites of acridine and dictamnine have been synthesised, from the corresponding cis-dihydrodiols. The achiral furoquinoline alkaloids robustine, γ-fagarine, haplopine, isohaplopine-3,3′-dimethylallylether and pteleine have been obtained, from either cis-dihydrodiol, catechol or Arene Oxide metabolites of dictamnine.
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Chemoenzymatic synthesis of monocyclic Arene Oxides and Arene hydrates from substituted benzene substrates.
Organic and Biomolecular Chemistry, 2013Co-Authors: Derek R Boyd, Narain D Sharma, Vera Ljubez, Peter K. M. Mcgeehin, Paul J. Stevenson, Marine Blain, Christopher C R AllenAbstract:Enantiopure cis-dihydrodiol bacterial metabolites of substituted benzene substrates were used as precursors, in a chemoenzymatic synthesis of the corresponding benzene Oxides and of a substituted oxepine, via dihydrobenzene Oxide intermediates. A rapid total racemization of the substituted benzene 2,3-Oxides was found to have occurred, via their oxepine valence tautomers, in accord with predictions and theoretical calculations. Reduction of a substituted Arene Oxide to yield a racemic Arene hydrate was observed. Arene hydrates have also been synthesised, in enantiopure form, from the corresponding dihydroArene Oxide or trans-bromoacetate precursors. Biotransformation of one Arene hydrate enantiomer resulted in a toluene-dioxygenase catalysed cis-dihydroxylation to yield a benzene cis-triol metabolite.
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cis dihydrodiol Arene Oxide and phenol metabolites of dictamnine key intermediates in the biodegradation and biosynthesis of furoquinoline alkaloids
Chemical Communications, 2005Co-Authors: Derek R Boyd, Narain D Sharma, Jonathan G Carroll, Pui L Loke, Colin Odowd, Christopher C R AllenAbstract:Biotransformation of the parent furoquinoline alkaloid dictamnine and its 4-chlorofuroquinoline precursor, using the B8/36 bacterial mutant strain of Sphingomonas yanoikuyae, yielded, via biphenyl dioxygenase-catalysed dihydroxylation, the first isolable alkaloid cis-dihydrodiol metabolites; these metabolites were used in the chemoenzymatic synthesis of postulated Arene Oxide and phenol intermediates, and a range of derived furoquinoline alkaloids.
Cecilia Cortez - One of the best experts on this subject based on the ideXlab platform.
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Arene Oxide synthesis phenanthrene 9 10 Oxide
Organic Syntheses, 2003Co-Authors: Cecilia Cortez, Ronald G HarveyAbstract:Arene Oxide SYNTHESIS: PHENANTHRENE-9,10-Oxide intermediate: trans-9,10-Dihydro-9,10-phenanthrenediol (1) product: Phenanthrene-9,10-Oxide (2) Keywords: elimination, dehydration; epOxide formation; reduction, CO choh; 9,10-phenanthrenequinone; tetrahydrofuran
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Organic Syntheses - Arene Oxide Synthesis: Phenanthrene‐9,10‐Oxide
Organic Syntheses, 2003Co-Authors: Cecilia Cortez, Ronald G HarveyAbstract:Arene Oxide SYNTHESIS: PHENANTHRENE-9,10-Oxide intermediate: trans-9,10-Dihydro-9,10-phenanthrenediol (1) product: Phenanthrene-9,10-Oxide (2) Keywords: elimination, dehydration; epOxide formation; reduction, CO choh; 9,10-phenanthrenequinone; tetrahydrofuran
