Asymmetric Cycloetherification by Bifunctional Organocatalyst
作者:Keisuke Asano、Seijiro Matsubara
DOI:10.1055/s-0036-1591592
日期:2018.11
synthesis could be effectively performed via kinetic resolution using ζ-hydroxyenone containing a secondary alcohol moiety using a chiral phosphoric acid catalyst. Attempts to obtain enantiomerically enriched tetrahydrofuran derivatives via an intramolecular oxy-Michael addition reaction of ε-hydroxyenone is discussed. Despite previous difficulties associated with the asymmetric induction of this reaction
cycloetherification via the kinetic resolution of secondary or tertiary alcohols using chiral phosphoric acid catalysts was developed, affording tetrahydropyrans (THPs) with two stereogenic centers. The cyclization of the recovered optically active alcohols afforded other stereoisomers of THPs. These protocols offer efficient syntheticroutes to various optically active THP derivatives, which are important
Mechanistic pathways in phosphate ester photochemistry
作者:Richard S. Givens、Rominder Singh
DOI:10.1016/0040-4039(91)85027-3
日期:1991.11
Initial bond breaking processes (homolysis vs heterolysis) of phosphateester photosolvolysis were probed by chemically trapping the reactive intermediates with a tethered 5-hexenyl group. The resulting mechanistic picture is a blend of homolytic and heterolytic pathways, where the heterolytic cleavage is dominant.
Substituted pyrido[1,2-a]pyrazines for the treatment of neurodegenerative and neurological disorders
申请人:Pfizer Inc.
公开号:US08916564B2
公开(公告)日:2014-12-23
Compounds and pharmaceutically acceptable salts of the compounds are disclosed, wherein the compounds have the structure of Formula I
as defined in the specification. Corresponding pharmaceutical compositions, methods of treatment, methods of synthesis, and intermediates are also disclosed.
Novel Pyrido[1,2-a]Pryazines And Their Use In The Treatment of Neurodegenerative and Neurological Disorders
申请人:Pfizer Inc.
公开号:US20150072990A1
公开(公告)日:2015-03-12
Compounds and pharmaceutically acceptable salts of the compounds are disclosed, wherein the compounds have the structure of Formula I
as defined in the specification. Corresponding pharmaceutical compositions, methods of treatment, methods of synthesis, and intermediates are also disclosed.