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Victor J. Hruby - One of the best experts on this subject based on the ideXlab platform.
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Thio‐Claisen Rearrangement Used in Preparing anti‐β‐Functionalized γ,δ‐Unsaturated Amino Acids: Scope and Limitations.
ChemInform, 2012Co-Authors: Zhihua Liu, Sukeshi J. Mehta, Kwang Soo Lee, Bryan Grossman, Gary S. Nichol, Victor J. HrubyAbstract:FeBr3-catalyzed or LDA-mediated S-alkylation of thioamides followed by Thio-Claisen Rearrangement allows a regio-, diastereo-, and enantioselective access to the title compounds.
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Thio-Claisen Rearrangement used in preparing anti-β-functionalized γ,δ-unsaturated amino acids: scope and limitations.
The Journal of organic chemistry, 2012Co-Authors: Zhihua Liu, Sukeshi J. Mehta, Kwang Soo Lee, Bryan Grossman, Gary S. Nichol, Victor J. HrubyAbstract:Multifunctionalized amino acids, especially amino acids with unsaturation, are important, demanding building blocks in peptide chemistry. Here we present a summary of our most recent study using the Thio-Claisen Rearrangement for the synthesis of anti-β-functionalized γ,δ-unsaturated amino acids. Investigations on scope, limitations, chemoselectivities and stereoselectivities regarding an FeBr3-catalyzed allylation strategy and a thio-enolate dianion formation strategy for asymmetric Thio-Claisen Rearrangement are documented. An explanation of the chirality crossover observed between the Eschenmoser–Claisen Rearrangement and the Thio-Claisen Rearrangement is proposed. Novel optically active Nα-protected amino acids with biologically interesting functional groups were prepared for the first time.
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Novel anti‐β‐Functionalized γ,δ‐Unsaturated Amino Acids via a Thio‐Claisen Rearrangement.
ChemInform, 2010Co-Authors: Zhihua Liu, Kwang Soo Lee, Bryan Grossman, Vlad K. Kumirov, Victor J. HrubyAbstract:Abstract A significantly improved thio–Claisen Rearrangement method was developed for preparing anti-β-functionalized γ,δ-unsaturated amino acids, which are extremely useful nonproteinogenic amino acids used in chemistry and biology research. The mild reaction condition successfully introduced base labile functional groups into the amino acids with excellent anti/syn selectivities.
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Novel anti-β-functionalized γ,δ-unsaturated amino acids via a thio–Claisen Rearrangement
Tetrahedron Letters, 2010Co-Authors: Zhihua Liu, Kwang Soo Lee, Bryan Grossman, Vlad K. Kumirov, Victor J. HrubyAbstract:Abstract A significantly improved thio–Claisen Rearrangement method was developed for preparing anti-β-functionalized γ,δ-unsaturated amino acids, which are extremely useful nonproteinogenic amino acids used in chemistry and biology research. The mild reaction condition successfully introduced base labile functional groups into the amino acids with excellent anti/syn selectivities.
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Enantioselective Synthesis of anti-β-Substituted γ,δ-Unsaturated Amino Acids: A Highly Selective Asymmetric Thio-Claisen Rearrangement
Organic letters, 2008Co-Authors: Zhihua Liu, Byoung J. Min, Joel Nyberg, Victor J. HrubyAbstract:A novel synthesis of optically active anti-1β-substituted γ,δ-unsaturated amino acids via a Thio-Claisen Rearrangement has been achieved. A 2,5-diphenylpyrrolidine was used as a C2-symmetric chiral auxiliary to control the stereochemistry, giving good yields and excellent diastereoselectivities and enantioselectivities.
Zhihua Liu - One of the best experts on this subject based on the ideXlab platform.
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Thio‐Claisen Rearrangement Used in Preparing anti‐β‐Functionalized γ,δ‐Unsaturated Amino Acids: Scope and Limitations.
ChemInform, 2012Co-Authors: Zhihua Liu, Sukeshi J. Mehta, Kwang Soo Lee, Bryan Grossman, Gary S. Nichol, Victor J. HrubyAbstract:FeBr3-catalyzed or LDA-mediated S-alkylation of thioamides followed by Thio-Claisen Rearrangement allows a regio-, diastereo-, and enantioselective access to the title compounds.
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Thio-Claisen Rearrangement used in preparing anti-β-functionalized γ,δ-unsaturated amino acids: scope and limitations.
The Journal of organic chemistry, 2012Co-Authors: Zhihua Liu, Sukeshi J. Mehta, Kwang Soo Lee, Bryan Grossman, Gary S. Nichol, Victor J. HrubyAbstract:Multifunctionalized amino acids, especially amino acids with unsaturation, are important, demanding building blocks in peptide chemistry. Here we present a summary of our most recent study using the Thio-Claisen Rearrangement for the synthesis of anti-β-functionalized γ,δ-unsaturated amino acids. Investigations on scope, limitations, chemoselectivities and stereoselectivities regarding an FeBr3-catalyzed allylation strategy and a thio-enolate dianion formation strategy for asymmetric Thio-Claisen Rearrangement are documented. An explanation of the chirality crossover observed between the Eschenmoser–Claisen Rearrangement and the Thio-Claisen Rearrangement is proposed. Novel optically active Nα-protected amino acids with biologically interesting functional groups were prepared for the first time.
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Novel anti‐β‐Functionalized γ,δ‐Unsaturated Amino Acids via a Thio‐Claisen Rearrangement.
ChemInform, 2010Co-Authors: Zhihua Liu, Kwang Soo Lee, Bryan Grossman, Vlad K. Kumirov, Victor J. HrubyAbstract:Abstract A significantly improved thio–Claisen Rearrangement method was developed for preparing anti-β-functionalized γ,δ-unsaturated amino acids, which are extremely useful nonproteinogenic amino acids used in chemistry and biology research. The mild reaction condition successfully introduced base labile functional groups into the amino acids with excellent anti/syn selectivities.
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Novel anti-β-functionalized γ,δ-unsaturated amino acids via a thio–Claisen Rearrangement
Tetrahedron Letters, 2010Co-Authors: Zhihua Liu, Kwang Soo Lee, Bryan Grossman, Vlad K. Kumirov, Victor J. HrubyAbstract:Abstract A significantly improved thio–Claisen Rearrangement method was developed for preparing anti-β-functionalized γ,δ-unsaturated amino acids, which are extremely useful nonproteinogenic amino acids used in chemistry and biology research. The mild reaction condition successfully introduced base labile functional groups into the amino acids with excellent anti/syn selectivities.
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Enantioselective Synthesis of anti-β-Substituted γ,δ-Unsaturated Amino Acids: A Highly Selective Asymmetric Thio-Claisen Rearrangement
Organic letters, 2008Co-Authors: Zhihua Liu, Byoung J. Min, Joel Nyberg, Victor J. HrubyAbstract:A novel synthesis of optically active anti-1β-substituted γ,δ-unsaturated amino acids via a Thio-Claisen Rearrangement has been achieved. A 2,5-diphenylpyrrolidine was used as a C2-symmetric chiral auxiliary to control the stereochemistry, giving good yields and excellent diastereoselectivities and enantioselectivities.
Krishna C. Majumdar - One of the best experts on this subject based on the ideXlab platform.
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Studies of Bioactive Heterocycles: Facile Thio‐Claisen Rearrangement of Propargylthio[1]benzopyran‐2‐ones.
ChemInform, 2010Co-Authors: Krishna C. Majumdar, Subhankar GhoshAbstract:Abstract Hitherto unreported 2 H -thiopyrano[3,2- c ][1]benzopyran-5-ones 6a – f are synthesized regioselectively in 79–85% yields by the Thio-Claisen Rearrangement of 4-propargylthio[1]benzopyran-2-ones 5a – f . The substrates 5a – f are synthesized by alkylation of hitherto unreported 4-mercaptocoumarins.
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Regioselective Synthesis of 4‐Aryloxymethylene‐2,3,5‐trihydrothiopyrano[3,2‐b]indoles by the thio‐Claisen Rearrangement of 3‐(4′‐Aryloxybut‐2′‐ynylthio)indoles.
ChemInform, 2008Co-Authors: Krishna C. Majumdar, S. Alam, S. MuhuriAbstract:A number of new 4-aryloxymethylene-2,3,5-trihydrothiopyrano[3,2-b]indoles are regioselectively synthesized in 78-84% yield by the Thio-Claisen Rearrangement of 3-(4′-aryloxybut-2′-ynylthio)indoles. The endocyclic double bonded products are isolated by introducing electron withdrawing acetyl group at the indole nitrogen and also can be converted to the corresponding exocyclic isomers by deacetylation and subsequent heating.
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Regioselective synthesis of 4 -aryloxymethylene -2,3,5-trihydrothiopyrano [3,2 -b]indoles by the Thio-Claisen Rearrangement of 3 -(4' -aryloxybut -2' -ynylthio )indoles
Journal of Heterocyclic Chemistry, 2007Co-Authors: Krishna C. Majumdar, S. Alam, S. MuhuriAbstract:A number of new 4-aryloxymethylene-2,3,5-trihydrothiopyrano[3,2-b]indoles are regioselectively synthesized in 78-84% yield by the Thio-Claisen Rearrangement of 3-(4′-aryloxybut-2′-ynylthio)indoles. The endocyclic double bonded products are isolated by introducing electron withdrawing acetyl group at the indole nitrogen and also can be converted to the corresponding exocyclic isomers by deacetylation and subsequent heating.
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Studies in Thio-Claisen Rearrangement. Synthesis of Thieno-[3,2-c]-quinolone Derivatives from 4-Allylthioquinolin-2-(1H)-ones.
ChemInform, 2005Co-Authors: Krishna C. Majumdar, D. Saha, M. GhoshAbstract:Abstract 4‐Allylthio‐1‐methylquinolin‐2‐(1H)‐ones in refluxing N,N‐diethylaniline underwent thio‐Claisen Rearrangement to give thieno[3,2‐c]quinolone derivatives.
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Studies in Thio‐Claisen Rearrangement: Synthesis of Thieno‐[3,2‐c]‐Quinolone Derivatives from 4‐Allylthioquinolin‐2‐(1H)‐Ones
Synthetic Communications, 2005Co-Authors: Krishna C. Majumdar, D. Saha, M. GhoshAbstract:Abstract 4‐Allylthio‐1‐methylquinolin‐2‐(1H)‐ones in refluxing N,N‐diethylaniline underwent thio‐Claisen Rearrangement to give thieno[3,2‐c]quinolone derivatives.
A. I. Meyers - One of the best experts on this subject based on the ideXlab platform.
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Asymmetric Synthesis of (‐)‐Trichodiene. Generation of Vicinal Stereogenic Quaternary Centers via the Thio‐Claisen Rearrangement.
ChemInform, 2010Co-Authors: R. Lemieux, A. I. MeyersAbstract:The use of chiral bicyclic lactams, in their thiocarbonyl form 9, has been shown to serve as important intermediates for producing α-quaternary alkyl derivatives 8, which were readily transformed into the title compound (−)-1. The reversibility of the Thio-Claisen Rearrangement, 15⇌8, was clearly demonstrated and appears to be unprecedented. Solvent effects to alter the equilibrium position were studied and found to have only a moderate, but beneficial effect. The title compound was obtained in 14% overall yield in 10 steps from bicyclic lactam, 9.
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Asymmetric Synthesis of (−)-Trichodiene. Generation of Vicinal Stereogenic Quaternary Centers via the Thio-Claisen Rearrangement
Journal of the American Chemical Society, 1998Co-Authors: R. Lemieux, A. I. MeyersAbstract:The use of chiral bicyclic lactams, in their thiocarbonyl form 9, has been shown to serve as important intermediates for producing α-quaternary alkyl derivatives 8, which were readily transformed into the title compound (−)-1. The reversibility of the Thio-Claisen Rearrangement, 15⇌8, was clearly demonstrated and appears to be unprecedented. Solvent effects to alter the equilibrium position were studied and found to have only a moderate, but beneficial effect. The title compound was obtained in 14% overall yield in 10 steps from bicyclic lactam, 9.
Bryan Grossman - One of the best experts on this subject based on the ideXlab platform.
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Thio‐Claisen Rearrangement Used in Preparing anti‐β‐Functionalized γ,δ‐Unsaturated Amino Acids: Scope and Limitations.
ChemInform, 2012Co-Authors: Zhihua Liu, Sukeshi J. Mehta, Kwang Soo Lee, Bryan Grossman, Gary S. Nichol, Victor J. HrubyAbstract:FeBr3-catalyzed or LDA-mediated S-alkylation of thioamides followed by Thio-Claisen Rearrangement allows a regio-, diastereo-, and enantioselective access to the title compounds.
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Thio-Claisen Rearrangement used in preparing anti-β-functionalized γ,δ-unsaturated amino acids: scope and limitations.
The Journal of organic chemistry, 2012Co-Authors: Zhihua Liu, Sukeshi J. Mehta, Kwang Soo Lee, Bryan Grossman, Gary S. Nichol, Victor J. HrubyAbstract:Multifunctionalized amino acids, especially amino acids with unsaturation, are important, demanding building blocks in peptide chemistry. Here we present a summary of our most recent study using the Thio-Claisen Rearrangement for the synthesis of anti-β-functionalized γ,δ-unsaturated amino acids. Investigations on scope, limitations, chemoselectivities and stereoselectivities regarding an FeBr3-catalyzed allylation strategy and a thio-enolate dianion formation strategy for asymmetric Thio-Claisen Rearrangement are documented. An explanation of the chirality crossover observed between the Eschenmoser–Claisen Rearrangement and the Thio-Claisen Rearrangement is proposed. Novel optically active Nα-protected amino acids with biologically interesting functional groups were prepared for the first time.
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Novel anti‐β‐Functionalized γ,δ‐Unsaturated Amino Acids via a Thio‐Claisen Rearrangement.
ChemInform, 2010Co-Authors: Zhihua Liu, Kwang Soo Lee, Bryan Grossman, Vlad K. Kumirov, Victor J. HrubyAbstract:Abstract A significantly improved thio–Claisen Rearrangement method was developed for preparing anti-β-functionalized γ,δ-unsaturated amino acids, which are extremely useful nonproteinogenic amino acids used in chemistry and biology research. The mild reaction condition successfully introduced base labile functional groups into the amino acids with excellent anti/syn selectivities.
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Novel anti-β-functionalized γ,δ-unsaturated amino acids via a thio–Claisen Rearrangement
Tetrahedron Letters, 2010Co-Authors: Zhihua Liu, Kwang Soo Lee, Bryan Grossman, Vlad K. Kumirov, Victor J. HrubyAbstract:Abstract A significantly improved thio–Claisen Rearrangement method was developed for preparing anti-β-functionalized γ,δ-unsaturated amino acids, which are extremely useful nonproteinogenic amino acids used in chemistry and biology research. The mild reaction condition successfully introduced base labile functional groups into the amino acids with excellent anti/syn selectivities.