Referenced in: none

Automatically associated channels: Kir2.3

Title: An alternative to the use of delta-lactam urethanes in the "ring switch" approach to higher homologues of AMPA-type glutamate antagonists.

Authors: Peter B Hitchcock, Shazia Rahman Masood, Douglas W Young

Journal, date & volume: Org. Biomol. Chem., 2003 Aug 7 , 1, 2682-8

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/12948192

Abstract
In an alternative strategy to the use of delta-lactam urethanes for the preparation of homologues of AMPA-type glutamate antagonists, we have used 5-exomethylene derivatives of pyroglutamate esters. The homochiral pyrazole amino acid derivatives 18 and 19 have been prepared in this way. Although this synthesis yields products with a glycine residue separated from a heterocyclic ring by two carbon atoms, the substitution of the heterocyclic ring is different from that in compounds prepared from delta-lactam urethanes. The branched chain compounds 32 and 33 have also been prepared in this way but the second chiral centre is epimerised during the synthesis. An interesting reaction, giving the pyridone 27 from the imino ether 24 and tert-butyl acetoacetate, is also reported.