Organocatalytic Asymmetric Reaction Cascade to Substituted Cyclohexylamines
作者:Jian Zhou、Benjamin List
DOI:10.1021/ja072134j
日期:2007.6.1
We report a new strategy for organocatalytic cascade reactions. Accordingly, enamine catalysis, iminium catalysis, and Bronsted acid catalysis can work in concert in a highlyenantioselective organocatalytic cascadesequence toward chiral cis-3-substituted cyclohexylamines. We found that an achiral amine in combination with a catalytic amount of a chiral Bronsted acid can accomplish an aldol additi
A new synthesis of 1,5-dicarbonyl compounds under neutral conditions
作者:Noboru Ono、Hideyoshi Miyake、Aritsune Kaji
DOI:10.1039/c39830000875
日期:——
Michael addition of α-nitroketones to methyl vinyl ketone or acrylaldehyde followed by denitration with Bu3SnH affords 1,5-dicarbonylcompounds in good yields.
yclohexanone (A). The positions of hydroboration are established by synthesis of the hydroboration/oxidation products. The cyanidation of the organoboranes derived from myrcene and diborane leads to a 23 mixture of A and 5-(2′-hydroxyethyl)-2-isopropylcyclohexanone, the structures of which are established by independent synthesis. The hydroboration of myrcene is shown to be relatively non-stereospecific
Regio- and Stereoselective Monoamination of Diketones without Protecting Groups
作者:Robert C. Simon、Barbara Grischek、Ferdinand Zepeck、Andreas Steinreiber、Ferdinand Belaj、Wolfgang Kroutil
DOI:10.1002/anie.201202375
日期:2012.7.2
Hitting the right target: Differentiation between two keto moieties was accomplished by a regio‐ and enantioselective bioamination employing ω‐transaminases. Using 1,5‐diketones as substrates gave access to the opticallypure 2,6‐disubstituted piperidine scaffold. The approach allowed the shortest synthesis of the alkaloid dihydropinidine, as well as its enantiomer, by choosing an appropriate ω‐transaminase
Prodrugs of guanfacine with amino acids or short peptides, pharmaceutical compositions containing such prodrugs and a method for providing therapeutic benefit in the treatment of ADHD/ODD (attention deficient hyperactivity disorder and oppositional defiance disorder) with guanfacine prodrugs are provided herein. Additionally, methods for minimizing or avoiding the adverse gastrointestinal side effects associated with guanfacine administration, as well as improving the pharmacokinetics of guanfacine are provided herein.