Enantioselective Epoxypyrrolidines via a Tandem Cycloaddition/Autoxidation in Air and Mechanistic Studies

A tandem cycloaddition/autoxidation reaction between heterocyclic ketene aminals and diazoester in air is described for the enantioselective preparation of epoxypyrrolidines. Notably, the results of mechanistic studies suggest that epoxide was oxidized from an sp³ C-C single bond, which is of mechanistic and practical interest as this protocol may be suitable for constructing other bioactive heterocyclic epoxides.

Diastereoselective Synthesis of Morphan Derivatives by Michael and Hetero-Michael Addition of 1,1-Enediamines to Quinone Monoketals

A general and concise method was developed for the synthesis of highly functionalized morphans 3-4 by the Michael and hetero-Michael addition reaction of different types of quinone monoketals 1 and 1,1-enediamines 2 in ethanol or 1,4-dioxane at reflux. This method is suitable for the efficient parallel syntheses of N-containing heterocycles. A library of highly functional morphan derivatives was easily constructed using the Michael/hetero-Michael reaction.

Synthesis and evaluation of the antitumor activity of highly functionalised pyridin-2-ones and pyrimidin-4-ones

The methods for selective synthesis of two novel types of compounds including pyridin-2-ones 3 and pyrimidin-4-ones 4 were developed. The antitumor bioactivity screening showed that certain compounds had potent antitumor activity.

Synthesis of bicyclic 2-pyridones by regioselective annulations of heterocyclic ketene aminals with anhydrides

An efficient strategy for the synthesis of substituted bicyclic 2-pyridones is developed. The proposed approach is based on the regioselective N-acylation of heterocyclic ketene aminals (HKAs) with methacrylic anhydride or crotonic anhydride.