Toposelective synthesis under thermodynamic control and bioactivities of topoisomers based on diethoxycarbonyl glycoluril derivatives

摘要

Six topoisomers consisting of diethoxy-carbonyl glycoluril have been successfully synthesized in one-pot by using a "figure-of-seven" building block through anti-connectivity and syn-connectivity reactions, respectively. The structures of all six topoisomers were first determined by X-ray crystallography. The finding that (+ -) CT isomers are the dominant products under thermodynamic control can be explained by the calculated relative energies of the six topoisomers. That the (+ -) CT isomers have the lowest energy is most likely due to the additional intramolecular electrostatic interactions between -NO2 and -OMe groups. The biological activities of the topoisomers were primitively investigated and the results of bioassay showed that the six topoisomers possessed obvious difference of herbicidal activity.