Development of two diastereoselective routes towards trans-4-aminomethyl-piperidin-3-ol building blocks
作者:Harrie J.M. Gijsen、Michel J.A. De Cleyn、Christopher J. Love、Michel Surkyn、Sven F.A. Van Brandt、Marc G.C. Verdonck、Luc Moens、Jef Cuypers、Jean-Paul R.M.A. Bosmans
DOI:10.1016/j.tet.2007.12.055
日期:2008.3
Two diastereoselective, scaleable routes towards trans-3,4-disubstituted piperidines with a 4-hydroxymethyl-3-hydroxy or 4-aminomethyl-3hydroxy substitution pattern are being described. In the first route, the 3,4-trans configuration was introduced regio- and diastereoselectively via a hydroboration/oxidation sequence starting from 4-hydroxymethylpyridine. In the second route, regioselective epoxide ring opening of N-benzyl-3,4-epoxy-piperidine was achieved with LiCN, in situ generated from acetocyanohydrin and LiNH(2), The regioselectivity of both the hydroboration and the epoxide ring opening was positively influenced by the presence of the basic piperidine nitrogen. Both routes have been optimized to be performed at large scale. (C) 2008 Elsevier Ltd. All rights reserved.
OXALAMIDES AS MODULATORS OF INDOLEAMINE 2,3-DIOXYGENASE