Protein kinase B (PknB) is an essential serine/threonine protein kinase required for Mycobacterium tuberculosis (M. tb) cell division and cell-wall biosynthesis. A high throughput screen using PknB identified a (E)-4-oxo-crotonic acid inhibitor, named YH-8, which was used as a scaffold for SAR investigations. A significant improvement in enzyme affinity was achieved. The results indicated that the
Highlyenantioselective Michael addition of 1,3‐dicarbonyl compounds and nitromethane to 4‐oxo‐4‐arylbutenoates catalyzed by N,N′‐dioxide–Sc(OTf)3 complexes has been developed. Using 0.5–2 mol % catalyst loading, various α‐stereogenic esters were obtained regioselectively with excellent yields (up to 97 %) and enantioselectivities (up to >99 % ee). Moreover, the reaction performed well under nearly
Substrate-Controlled, One-Pot Synthesis: Access to Chiral Chroman-2-one and Polycyclic Derivatives
作者:Xue-Li Sun、Ying-Han Chen、Dan-Yang Zhu、Yan Zhang、Yan-Kai Liu
DOI:10.1021/acs.orglett.6b00160
日期:2016.2.19
appropriate choice of electrophiles, one-pot, multicomponent, enantioselective domino reactions have been realized which contain a five-step sequence and provide highly efficient access to potentially bioactive chroman-2-one derivatives as a single diastereoisomer with excellent enantioselectivities and in high yields. This new strategy could significantly improve the previous protocol by directly starting
A useful Michael addition reaction using nitroalkanes as the nucleophile and 4-oxo-enoates as the Michael acceptor has been disclosed, and the reaction allows expedient access to functionalized chiral gamma-keto esters in high yields and excellent enantioselectivities (up to 98% ee), with a low catalyst loading.
The reaction of alkyl 4-hydroxy-2-alkynoates and 4-hydroxy-2-alkyn-1-ones with palladium tributylammonium formate and with tributylamine: Preparation of 1,4-dicarbonyl compounds
作者:A. Arcadi、S. Cacchi、F. Marinelli、D. Misiti
DOI:10.1016/s0040-4039(00)80324-x
日期:1988.1
Ethyl 4-oxo-2-alkenoates and 1,4-dioxo-2-alkenes are easily prepared by treating ethyl 4-hydroxy-2-alkynoates and 4-hydroxy-2-alkyn-1-ones with n-tributylamine. Treatment of ethyl 4-hydroxy-2-alkynoates and 4-hydroxy-2-alkyn-1-ones with palladium-tributylammonium formate produces ethyl 4-oxo-alkanoates and 1,4-alkandiones in good to high yield through a novel one-pot isomerization/hydrogenation reaction