Expeditive synthesis of homochiral fused tri- and tetrazoles–piperazines from β-amino alcohols
作者:François Couty、François Durrat、Damien Prim
DOI:10.1016/j.tetlet.2004.03.092
日期:2004.5
N-Cyanomethyl and N-propargyl beta-amino alcohols are chlorinated with SOCl2 and treated with NaN3 in DMSO. A Substitution/cycloaddition process affords in good yields, with high diastereoselectivity and a regioselectivity depending on the substitution pattern of the starting amino alcohol, fused tri- and tetrazoles-pipci-azines. These heterocycles were further lithiated with n-BuLi at the benzylic position and reacted diastereoselectively with a range of electrophiles. (C) 2004 Elsevier Ltd. All rights reserved.
Azetidinic amino acids: stereocontrolled synthesis and pharmacological characterization as ligands for glutamate receptors and transporters
azetidinic amino acids, that can be envisioned as C-4 alkyl substituted analogues of trans-2-carboxyazetidine-3-acetic acid (t-CAA) and/or conformationally constrained analogues of (R)- or (S)-glutamic acid (Glu) have been synthesized in a diastereo- and enantiomerically pure form from beta-amino alcohols through a straightforward five step sequence. The key step of this synthesis is an original anionic
A set of enantiomerically pure N-disubstituted β-amino alcohols was chlorinated by treatment with thionyl chloride. This reaction gave a mixture of regioisomeric chlorides that could be equilibrated to the more stable regioisomer by heating in DMF. The chlorides thus obtained were engaged in an intramolecular anionic ring-closure and gave access to fully protected enantio- and diastereomerically pure 2,3-cis-disubstituted azetidinic amino acids. One of the latter was deprotected and included in a short peptide sequence.