The Experts below are selected from a list of 21279 Experts worldwide ranked by ideXlab platform
Darren J. Dixon - One of the best experts on this subject based on the ideXlab platform.
-
One-pot catalytic enantioselective synthesis of Tetrahydropyridines via a nitro-Mannich/hydroamination cascade.
Organic Letters, 2012Co-Authors: David M. Barber, Hitesh J. Sanganee, Darren J. DixonAbstract:The highly enantioselective preparation of synthetically useful tetrahydropyridine derivatives employing a one-pot nitro-Mannich/hydroamination cascade is reported. This approach utilizes an asymmetric organocatalytic nitro-Mannich reaction followed by a gold-catalyzed alkyne hydroamination/isomerization sequence that yields the desired Tetrahydropyridines in good yields and high diastereo- and enantioselectivities.
-
one pot catalytic enantioselective synthesis of Tetrahydropyridines via a nitro mannich hydroamination cascade
Organic Letters, 2012Co-Authors: David M. Barber, Hitesh J. Sanganee, Darren J. DixonAbstract:The highly enantioselective preparation of synthetically useful tetrahydropyridine derivatives employing a one-pot nitro-Mannich/hydroamination cascade is reported. This approach utilizes an asymmetric organocatalytic nitro-Mannich reaction followed by a gold-catalyzed alkyne hydroamination/isomerization sequence that yields the desired Tetrahydropyridines in good yields and high diastereo- and enantioselectivities.
Koji Urano - One of the best experts on this subject based on the ideXlab platform.
-
measurement of baseline locomotion and other behavioral traits in a common marmoset model of parkinson s disease established by a single administration regimen of 1 methyl 4 phenyl 1 2 3 6 tetrahydropyridine providing reference data for efficacious p
Behavioural Pharmacology, 2020Co-Authors: Kiyoshi Ando, Takashi Inoue, Keigo Hikishima, Yuji Komaki, Kenji Kawai, Ryo Inoue, Chiyoko Nishime, Eiko Nishinaka, Koji UranoAbstract:Baseline locomotion and behavioral traits in the common marmoset Parkinson's disease model were examined to provide basic information for preclinical evaluations of medical treatments. A single regimen of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine at a cumulative dose of 5 mg/kg as the free base over three consecutive days was administered subcutaneously to 10 marmosets. Data obtained from these marmosets were compared to pre-1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine levels or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine free marmosets. After the single regimen, reduced daily locomotion, a measure of immobility (a primary sign of Parkinsonism), was observed for more than a year. A moving tremor was also observed by visual inspection during this period. When apomorphine (0.13 mg/kg, s.c.) was administered, either right or left circling behavior was observed in a cylindrical chamber in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine marmosets, suggestive of unequal neural damage between the two brain hemispheres to different extents. MRI revealed that T1 relaxation time in the right substantia nigra correlated with right circling in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine marmosets. Histology was supportive of dopaminergic neural loss in the striatum. These results increase our understanding of the utility and limitations of the Parkinson's disease model in marmosets with a single 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine regimen, and provide reference data for efficacious preclinical evaluations.
Jon T Njardarson - One of the best experts on this subject based on the ideXlab platform.
-
synthesis of 1 2 3 6 Tetrahydropyridines via aminophosphate enabled anionic cascade and acid catalyzed cyclization approaches
ChemInform, 2015Co-Authors: Pradipta Das, Jon T NjardarsonAbstract:Two new approaches towards Tetrahydropyridines are reported, both employing a strategic phosphate substituent on the nitrogen atom.
-
synthesis of 1 2 3 6 Tetrahydropyridines via aminophosphate enabled anionic cascade and acid catalyzed cyclization approaches
Organic Letters, 2015Co-Authors: Pradipta Das, Jon T NjardarsonAbstract:Two new approaches for forming 1,2,3,6-Tetrahydropyridines are reported. Both reactions employ a strategic phosphate substituent on the nitrogen atom. In the presence of an additional phosphate substituent (X = P = O(OEt)2) an anionic cascade can by triggered upon treatment with base. Alternatively, when X = H the same 1,2,3,6-tetrahydropyridine product can be accessed via an acid catalyzed cyclization.
-
Synthesis of 1,2,3,6-Tetrahydropyridines via Aminophosphate Enabled Anionic Cascade and Acid Catalyzed Cyclization Approaches
2015Co-Authors: Pradipta Das, Jon T NjardarsonAbstract:Two new approaches for forming 1,2,3,6-Tetrahydropyridines are reported. Both reactions employ a strategic phosphate substituent on the nitrogen atom. In the presence of an additional phosphate substituent (X = P = O(OEt)2) an anionic cascade can by triggered upon treatment with base. Alternatively, when X = H the same 1,2,3,6-tetrahydropyridine product can be accessed via an acid catalyzed cyclization
Keigo Hikishima - One of the best experts on this subject based on the ideXlab platform.
-
measurement of baseline locomotion and other behavioral traits in a common marmoset model of parkinson s disease established by a single administration regimen of 1 methyl 4 phenyl 1 2 3 6 tetrahydropyridine providing reference data for efficacious p
Behavioural Pharmacology, 2020Co-Authors: Kiyoshi Ando, Takashi Inoue, Keigo Hikishima, Yuji Komaki, Kenji Kawai, Ryo Inoue, Chiyoko Nishime, Eiko Nishinaka, Koji UranoAbstract:Baseline locomotion and behavioral traits in the common marmoset Parkinson's disease model were examined to provide basic information for preclinical evaluations of medical treatments. A single regimen of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine at a cumulative dose of 5 mg/kg as the free base over three consecutive days was administered subcutaneously to 10 marmosets. Data obtained from these marmosets were compared to pre-1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine levels or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine free marmosets. After the single regimen, reduced daily locomotion, a measure of immobility (a primary sign of Parkinsonism), was observed for more than a year. A moving tremor was also observed by visual inspection during this period. When apomorphine (0.13 mg/kg, s.c.) was administered, either right or left circling behavior was observed in a cylindrical chamber in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine marmosets, suggestive of unequal neural damage between the two brain hemispheres to different extents. MRI revealed that T1 relaxation time in the right substantia nigra correlated with right circling in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine marmosets. Histology was supportive of dopaminergic neural loss in the striatum. These results increase our understanding of the utility and limitations of the Parkinson's disease model in marmosets with a single 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine regimen, and provide reference data for efficacious preclinical evaluations.
Jean-pierre Hurvois - One of the best experts on this subject based on the ideXlab platform.
-
modified fry cyanation of a chiral pyridinium salt asymmetric syntheses of coniine and solenopsin a
European Journal of Organic Chemistry, 2013Co-Authors: Van Ha Vu, Laurie-anne Jouanno, Adele Cheignon, Sourisak Sinbandhit, Vincent Dorcet, Thierry Roisnel, Jean-pierre HurvoisAbstract:The synthesis of chiral 2-cyano-Δ4-tetrahydropyridine 5 was carried out in 85 % yield through a modified two-step Fry reductive cyanation of pyridinium salt (+)-3c that used lithium triethylborohydride as the hydride donor. An alkylation–reduction sequence provided 2-alkyl-substituted Tetrahydropyridines (+)-10a and (+)-10b in 72–75 % yield after chromatographic purification. This protocol has been applied to the asymmetric syntheses of piperidine alkaloids (–)-coniine and (–)-solenopsin A.
-
Modified Fry Cyanation of a Chiral Pyridinium Salt: Asymmetric Syntheses of (–)-Coniine and (–)-Solenopsin A
European Journal of Organic Chemistry, 2013Co-Authors: Laurie-anne Jouanno, Adele Cheignon, Sourisak Sinbandhit, Vincent Dorcet, Thierry Roisnel, Jean-pierre HurvoisAbstract:The synthesis of chiral 2-cyano-Δ4-tetrahydropyridine 5 was carried out in 85 % yield through a modified two-step Fry reductive cyanation of pyridinium salt (+)-3c that used lithium triethylborohydride as the hydride donor. An alkylation–reduction sequence provided 2-alkyl-substituted Tetrahydropyridines (+)-10a and (+)-10b in 72–75 % yield after chromatographic purification. This protocol has been applied to the asymmetric syntheses of piperidine alkaloids (–)-coniine and (–)-solenopsin A.
