The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform
Marco Bella - One of the best experts on this subject based on the ideXlab platform.
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biomimetic organocatalytic asymmetric synthesis of 2 substituted piperidine type alkaloids and their analogues
ChemInform, 2012Co-Authors: Mattia Riccardo Monaco, Polyssena Renzi, Daniele Scarpino M Schietroma, Marco BellaAbstract:The method allows a new, highly enantioselective access to the alkaloid Pelletierine and its analogues.
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biomimetic organocatalytic asymmetric synthesis of 2 substituted piperidine type alkaloids and their analogues
Organic Letters, 2011Co-Authors: Mattia Riccardo Monaco, Polyssena Renzi, Daniele Scarpino M Schietroma, Marco BellaAbstract:Natural substances such as Pelletierine and its analogues have been prepared in up to 97% ee and good yield by a protective-group-free, biomimetic approach. Usage of benzonitrile or acetonitrile as solvents effectively prevents product racemization.
Yan Lok-hang - One of the best experts on this subject based on the ideXlab platform.
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Approche biomimétique des manadomanzamines et préparation d'analogues de la pelletiérine pour la synthèse biomimétique d'alcaloïdes de lycopodes
2011Co-Authors: Yan Lok-hang, Poupon ErwanAbstract:Au cours de ce travail, nous nous sommes intéressés dans une première partie à la synthèse biomimétique d alcaloïdes de type manzamines et plus particulièrement, aux manadomanzamines. Une étude de la réactivité des deux intermédiaires clés de leur biogenèse, les glutaconaldéhydes et les aminopentadiènals, a été entreprise. Ces mêmes molécules ont ensuite été utilisées comme équivalents synthétiques dans une synthèse biomimétique du squelette pentacyclique de la manadomanzamine A. Une seconde partie est consacrée à la préparation d analogues stables de la pelletiérine en vue d une synthèse biomimétique d alcaloïdes du genre Lycopodium.This work is dedicated to the biomimetic synthesis of complex polycyclic alkaloids namely the manzamine alkaloids and especially to manadomanzamine. The biogenetic hypotheses postulated for these alkaloids are reported in a first introductory chapter. A few examples of manzamine alkaloids biogenesis are described and compared. The second chapter is focused on the reactivity of reactive units (considered as simplified models of two key biosynthetic intermediates, namely glutaconaldehydes and aminopentadienals) resulting from the ring-opening of pyridinium salts, and their implication in natural products synthesis. Particularly detailed are the investigations conducted on 5-dimethylamino-2-methylpenta-2,4-dienal and the condensation of potassium glutaconaldehyde onto a pyridinium salt. The chemistry of these reactive units has been exploited to design several model studies towards the synthesis of pentacyclic indole nucleus of manadomanzamine A, isolated from an Indonesian sponge Acanthostrongylophora sp.. These biomimetic models, elaborated from a biosynthetic intermediate postulated in our biosynthesis hypothesis have culminated in the synthesis of the central pentacyclic indole nucleus. The last chapter reports the preparation of more or less oxidized analogs of Pelletierine, the well known alkaloid isolated from Punica granatum. Compounds such as phenyloxazoloPelletierine have been prepared and their reactivity investigated in view of the biomimetic synthesis of Lycopodium alkaloids.PARIS11-SCD-Bib. électronique (914719901) / SudocSudocFranceF
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Approche biomimétique des manadomanzamines et préparation d’analogues de la pelletiérine pour la synthèse biomimétique d’alcaloïdes de lycopodes
HAL CCSD, 2011Co-Authors: Yan Lok-hangAbstract:This work is dedicated to the biomimetic synthesis of complex polycyclic alkaloids namely the manzamine alkaloids and especially to manadomanzamine. The biogenetic hypotheses postulated for these alkaloids are reported in a first introductory chapter. A few examples of manzamine alkaloids biogenesis are described and compared.The second chapter is focused on the reactivity of reactive units (considered as simplified models of two key biosynthetic intermediates, namely glutaconaldehydes and aminopentadienals) resulting from the ring-opening of pyridinium salts, and their implication in natural products synthesis. Particularly detailed are the investigations conducted on 5-dimethylamino-2-methylpenta-2,4-dienal and the condensation of potassium glutaconaldehyde onto a pyridinium salt.The chemistry of these reactive units has been exploited to design several model studies towards the synthesis of pentacyclic indole nucleus of manadomanzamine A, isolated from an Indonesian sponge Acanthostrongylophora sp.. These biomimetic models, elaborated from a biosynthetic intermediate postulated in our biosynthesis hypothesis have culminated in the synthesis of the central pentacyclic indole nucleus.The last chapter reports the preparation of more or less oxidized analogs of Pelletierine, the well known alkaloid isolated from Punica granatum. Compounds such as phenyloxazoloPelletierine have been prepared and their reactivity investigated in view of the biomimetic synthesis of Lycopodium alkaloids.Au cours de ce travail, nous nous sommes intéressés dans une première partie à la synthèse biomimétique d’alcaloïdes de type manzamines et plus particulièrement, aux manadomanzamines. Une étude de la réactivité des deux intermédiaires clés de leur biogenèse, les glutaconaldéhydes et les aminopentadiènals, a été entreprise. Ces mêmes molécules ont ensuite été utilisées comme équivalents synthétiques dans une synthèse biomimétique du squelette pentacyclique de la manadomanzamine A. Une seconde partie est consacrée à la préparation d’analogues stables de la pelletiérine en vue d’une synthèse biomimétique d’alcaloïdes du genre Lycopodium
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Biomimetic approach to manadomanzamines and preparation of derivatives of Pelletierine for biomimetic synthesis of Lycopodium alkaloids.
2011Co-Authors: Yan Lok-hangAbstract:Au cours de ce travail, nous nous sommes intéressés dans une première partie à la synthèse biomimétique d’alcaloïdes de type manzamines et plus particulièrement, aux manadomanzamines. Une étude de la réactivité des deux intermédiaires clés de leur biogenèse, les glutaconaldéhydes et les aminopentadiènals, a été entreprise. Ces mêmes molécules ont ensuite été utilisées comme équivalents synthétiques dans une synthèse biomimétique du squelette pentacyclique de la manadomanzamine A. Une seconde partie est consacrée à la préparation d’analogues stables de la pelletiérine en vue d’une synthèse biomimétique d’alcaloïdes du genre Lycopodium.This work is dedicated to the biomimetic synthesis of complex polycyclic alkaloids namely the manzamine alkaloids and especially to manadomanzamine. The biogenetic hypotheses postulated for these alkaloids are reported in a first introductory chapter. A few examples of manzamine alkaloids biogenesis are described and compared. The second chapter is focused on the reactivity of reactive units (considered as simplified models of two key biosynthetic intermediates, namely glutaconaldehydes and aminopentadienals) resulting from the ring-opening of pyridinium salts, and their implication in natural products synthesis. Particularly detailed are the investigations conducted on 5-dimethylamino-2-methylpenta-2,4-dienal and the condensation of potassium glutaconaldehyde onto a pyridinium salt. The chemistry of these reactive units has been exploited to design several model studies towards the synthesis of pentacyclic indole nucleus of manadomanzamine A, isolated from an Indonesian sponge Acanthostrongylophora sp.. These biomimetic models, elaborated from a biosynthetic intermediate postulated in our biosynthesis hypothesis have culminated in the synthesis of the central pentacyclic indole nucleus. The last chapter reports the preparation of more or less oxidized analogs of Pelletierine, the well known alkaloid isolated from Punica granatum. Compounds such as phenyloxazoloPelletierine have been prepared and their reactivity investigated in view of the biomimetic synthesis of Lycopodium alkaloids
Miguel Yus - One of the best experts on this subject based on the ideXlab platform.
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stereoselective coupling of n tert butanesulfinyl aldimines and β keto acids access to β amino ketones
Journal of Organic Chemistry, 2017Co-Authors: Alejandro Lahosa, Tatiana Soler, Ana Arrieta, Fernando P Cossio, Francisco Foubelo, Miguel YusAbstract:The reaction of chiral N-tert-butanesulfinyl aldimines with β-keto acids under basic conditions at room temperature proceeds with high levels of diastereocontrol, leading to β-amino ketones in high yields. Based on DFT calculations, an eight-membered cyclic transition state involving coordination of the lithium atom to the oxygens of carboxylate and sulfinyl units was proposed, being in agreement with the observed experimental diastereomeric ratios. The synthesis of the piperidine alkaloid (−)-Pelletierine was successfully undertaken in order to demonstrate the utility of this methodology.
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Stereoselective Coupling of N-tert-Butanesulfinyl Aldimines and β‑Keto Acids: Access to β‑Amino Ketones
2017Co-Authors: Alejandro Lahosa, Tatiana Soler, Ana Arrieta, Francisco Foubelo, Fernando P. Cossío, Miguel YusAbstract:The reaction of chiral N-tert-butanesulfinyl aldimines with β-keto acids under basic conditions at room temperature proceeds with high levels of diastereocontrol, leading to β-amino ketones in high yields. Based on DFT calculations, an eight-membered cyclic transition state involving coordination of the lithium atom to the oxygens of carboxylate and sulfinyl units was proposed, being in agreement with the observed experimental diastereomeric ratios. The synthesis of the piperidine alkaloid (−)-Pelletierine was successfully undertaken in order to demonstrate the utility of this methodology
Takefumi Momose - One of the best experts on this subject based on the ideXlab platform.
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a new asymmetric entry to 2 substituted piperidines a concise synthesis of coniine Pelletierine δ coniceine and epidihydropinidine
Tetrahedron-asymmetry, 1996Co-Authors: Hiroki Takahata, Minoru Kubota, Seiki Takahashi, Takefumi MomoseAbstract:Abstract A new asymmetric route to 2-substituted piperidines involving the Sharpless asymmetric dihydroxylation (AD) of 5-hexenylazide 1 and an intramolecular aminocyclization as crucial steps and its application to the asymmetric synthesis of four piperidine alkaloids, (+)-coniine 2, (−)-Pelletierine 3, (+)-δ-coniceine 4, and (+)-epidihydropinidine 5 is presented.
Mattia Riccardo Monaco - One of the best experts on this subject based on the ideXlab platform.
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biomimetic organocatalytic asymmetric synthesis of 2 substituted piperidine type alkaloids and their analogues
ChemInform, 2012Co-Authors: Mattia Riccardo Monaco, Polyssena Renzi, Daniele Scarpino M Schietroma, Marco BellaAbstract:The method allows a new, highly enantioselective access to the alkaloid Pelletierine and its analogues.
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biomimetic organocatalytic asymmetric synthesis of 2 substituted piperidine type alkaloids and their analogues
Organic Letters, 2011Co-Authors: Mattia Riccardo Monaco, Polyssena Renzi, Daniele Scarpino M Schietroma, Marco BellaAbstract:Natural substances such as Pelletierine and its analogues have been prepared in up to 97% ee and good yield by a protective-group-free, biomimetic approach. Usage of benzonitrile or acetonitrile as solvents effectively prevents product racemization.