A new asymmetric synthetic route to substituted piperidines
作者:M. Somi Reddy、M. Narender、K. Rama Rao
DOI:10.1016/j.tet.2006.10.073
日期:2007.1
An asymmetric synthesis of substituted piperidines has been described. β-Cyclodextrin- or oxazaborolidine-catalyzed asymmetric reduction of α-azido aryl ketones to the corresponding alcohols has been employed as the key step along with ring closing metathesis and selective dihydroxylation.
A new access to polyhydroxy piperidines of the azasugar class: synthesis and glycosidase inhibition studies
作者:Ganesh Pandey、Manmohan Kapur、M. Islam Khan、Sushama M. Gaikwad
DOI:10.1039/b307455b
日期:——
A new synthetic strategy has been devised to access a variety of polyhydroxylated piperidines belonging to the azasugar class of glycosidase inhibitors. The key precursor (3aR, 7aR)-5-benzyl-2,2-dimethyl-7-methylenehexahydro[1,3]dioxo[4,5-c]pyridine is obtained by photoinduced electron transfer (PET) cyclization of the corresponding α-trimethylsilylmethylamine radical cation to the tethered acetylene functionality. The new molecules have been evaluated for inhibitory properties for certain β-glycosidases and have been found to be moderate to weak inhibitors of the enzymes under study.
[GRAPHICS]The phenylglycinol-derived 2-pyridone 1 undergoes m-CPBA oxidation steroselectively leading to the chiral nonracemic unsaturated bicyclic hydroxylactam 2, from which the enantioselective synthesis of (3R,5R)-3,4,5-trihydroxypiperidine (16) and the formal synthesis of the azasugar epiisofagomine are described. The enantioselective synthesis of (S)-N-Boc-3-hydroxypiperidine and (3R,4S)-3,4-dihydroxyplperidlne is also reported.
Design and Development of a Common Synthetic Strategy for a Variety of 1-<i>N</i>-Iminosugars
作者:Ganesh Pandey、Manmohan Kapur
DOI:10.1021/ol026711e
日期:2002.10.1
[GRAPHICS]A new synthetic strategy has been developed for a general approach toward the synthesis of a variety of 1-N-iminosugar-type glycosidase inhibitors utilizing precursors developed by the PET-mediated cyclization of alpha-trimethylsilylmethylamine radical cation to a tethered pi-functionality.