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Piperidine Ring (piperidine + ring)

Distribution by Scientific Domains

Chemistry	100%

Selected Abstracts

Asymmetric Total Synthesis of (+)-6- epi -Castanospermine by the Stereoselective Formation of a syn,anti Acetylenic 2-Amino-1,3-diol Stereotriad

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2010
Julien Louvel
Abstract The asymmetric total synthesis of (+)-6- epi -castanospermine (1) is described herein. In this synthesis the diastereoselective addition of a racemic allenylzinc reagent to an enantiopure ,-alkoxy- tert -butylsulfinylimine is the key step and is followed by the formation of a piperidine ring by ring-closing metathesis and subsequent syn -dihydroxylation of an alkene. [source]

Synthesis and biodistribution of novel 99mTc-nitrido methylpiperidine dithioformate derivatives as potential brain imaging agents

JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 6 2009
Jie Lu
Abstract Three dithioformate ligands with methyl substituted on the piperidine rings, potassium 1-(2-methylpiperidine-1-yl)-dithioformate (2-mp), potassium 1-(3-methylpiperidine-1-yl)-dithioformate (3-mp) and potassium 1-(4-methylpiperidine-1-yl)-dithioformate (4-mp) were synthesized. The corresponding 99mTc-nitrido complexes were prepared in high yield (>95%) through the [99mTcN] intermediate and characterized by thin layer chromatography and high-performance liquid chromatography. All the neutral 99mTc-nitrido complexes were stable under physiological conditions and lipophilic with log,P values between 1.40 and 1.58. In vivo biodistribution results showed that all the 99mTc-nitrido complexes displayed high brain uptakes and long retention times. Among them, 99mTcN-4mp, demonstrated the best properties for brain imaging with the brain uptake 3.40±0.24, 3.22±0.31, 2.72±0.28 and 2.22±0.18% ID/g at 5, 30, 60 and 120,min p.i., respectively. Moreover, the influence of stereochemistry of the 99mTcN complexes with methyl substitution on ortho, meta and para positions on piperidine ring on the biodistribution properties were investigated with B3LYP/6-31G*(LANL2DZ for Tc) method using the Gaussian 03 program package. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Forced twin-chair conformation in 7-benzoyl- and 7-phenylacetyl- r -2,c -4,t -6,t -8-tetraphenyl-3-thia-7-azabicyclo[3.3.1]nonanes with 1,3-diaxial phenyl groups in the piperidine ring: single- and double-layered supramolecular sheets built from C,H...O and C,H...,(arene) hydrogen bonds

ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2010
Chinniah Sakthivel
The crystal structures of 7-benzoyl- r -2,c -4,t -6,t -8-tetraphenyl-3-thia-7-azabicyclo[3.3.1]nonane, C38H33NOS, (I), and r -2,c -4,t -6,t -8-tetraphenyl-7-phenylacetyl-3-thia-7-azabicyclo[3.3.1]nonane [systematic name: 2-phenyl-1-(r -2,c -4,t -6,t -8-tetraphenyl-3-thia-7-azabicyclo[3.3.1]nonan-7-yl)ethanone], C39H35NOS, (II), both reveal a forced twin-chair conformation with the 1,3-diaxial phenyl groups in the piperidine ring, and flattening at the N-atom end of the piperidine ring of the bicyclic system. In the crystal structure of (I), molecules are linked into sheets by a combination of two weak C,H...O and one C,H...,(arene) hydrogen bond, while in the crystal structure of (II), the molecules extend into double-layered sheets assisted by three C,H...,(arene) hydrogen bonds. [source]