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A method for the synthesis of 2-(1 H -imidazol-1-yl)-4 H -chromen-4-one derivatives (IMCMs) from 3-cyanochromones and α-isocyanoacetates via a one-pot cascade reaction involving a 1,2-addition, Michael reaction, ring-closing, tautomerization, ring-opening, and [3 + 2] cyclization was enabled by refluxing a mixture of the starting materials in THF in the presence of Ag 2 CO 3 as a catalyst. The cascade reaction resulted in the formation of five bonds and the cleavage of two bonds, including a triple bond, in one pot. This protocol enabled not only the synthesis of functionalized imidazoles (i.e., IMCMs) but also the synthesis of functionally useful enamine building blocks. This strategy is suitable for combinatorial and parallel syntheses of IMCMs.

A novel protocol for the construction of highly functionalized bipyrimidine derivatives 4 and 5 from 3-formyl-chromones, ethyl 2-(pyridine-2-yl)acetate derivatives, and amidine hydrochlorides via an interesting and considerably complex multi-component cascade reaction was developed. The cascade reaction was manifested by refluxing a mixture of the three substrates in acetonitrile or DMF along with Cs2CO3. A series of 4,5-dihydro-[4,5'-bipyrimidin]-6(1H)-ones (DBPMOs) 4 was constructed regioselectively in suitable to excellent yields. Moreover, intermediates 4 then underwent a novel, metal- and oxidant-free cascade reaction to produce a series of [4,5'-bipyrimidin]-6(1H)-ones (BPMOs) 5. The formation of the bipyrimidine derivatives 4-5 was enabled by the formation of five bonds and the cleavage of one bond in one pot. This protocol can be used in the synthesis of functionalized bipyrimidine derivatives via a multi-component one-pot cascade reaction rather than multi-step reactions, which is suitable for both combinatorial and parallel syntheses of bipyrimidine derivatives.

The distribution information of Lomatogonium rotatum. was collected by interview investigation and field survey, and 55 related environmental factors were collected, the habitat suitability study was conducted based on geographic information system (GIS) and maximum entropy model. The AUCs of ROC curve were both above 0.99, indicating that the predictive results with the maximum model were highly precise. The results showed that 13 major environmental factors have obvious influence on ecology suitability distributions of L. rotatum, including month average temperature of February et al., the suitable distribution areas are mainly concentrated in the east-central of Inner Mongolia, including Hexigten banner, Duolun county, Zhenglan banner et al., The zoning results basically coincide with the genuine producing areas, and further afford new suitable distribution areas, which can provide reference for L. rotatum's wild nursery and the siting of introduction and cultivation.