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A catalytic asymmetric vinylogous aldol reaction between β,γ-unsaturated amides and isatins has been developed. In the presence of 10 mol% of tertiary amine-thiourea C7, the vinylogous reaction has been achieved in up to 98% yield and up to 99% ee (26 examples). This methodology provides an efficient approach to construct chiral multifunctional 3-hydroxy-2-oxindoles. Moreover, the transformations of the chiral products, including the esterification of amides, the hydrogenation of the C–C double bond and further conversion to spirolactones, have been investigated. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Nineteen new cadinane‐involving sesquiterpenoid dimers, artemordins A—S (1—19), together with 13 known SDs (20—32) were isolated from Artemisia ordosica. Their structures and absolute configurations were established by comprehensive spectral analyses, X‐ray single crystal diffraction, theoretical ECD, and NMR calculations. Chemically, artemordins A—F (1—6) were the first examples of two cadinane units constructed by unprecedented C‐3−C‐15′ or C‐3−C‐13′ single bond with an oxido‐rearranged 6/5/6/6 fused ring system; artemordins G—K (7—11) were biogenetically connected by [4 + 2] cycloaddition reaction and artemordins G—J (7—10) possessed a novel 5/6/6/6/6/6/5‐heptacyclic fused ring system. Artemordins L—S (12—19) were formed by esterification, which involved three different types of sesquiterpenoids. Antihepatoma assay suggested that the most active compounds, artemordins B and H (2 and 8), exhibited inhibitory activities on three hepatoma cell lines with IC50 values of 26.9 and 25.1 μmol/L (HepG2), 29.5 and 18.3 μmol/L (Huh7), 19.7 and 15.7 μmol/L (SK‐Hep‐1). [ABSTRACT FROM AUTHOR]

In the field of molecular nonequilibrium transports, physical mechanisms of multiple reaction dynamics of these systems are the core of deep understanding complex reactions and transport mechanisms. In order to explore related mechanisms, establishing multiple systems coupled with tremendous exit dynamics and studying their exit dynamics properties are quite vital. Beyond previous researches, new stochastic transport processes are emphasized here. Multiple new exit dynamic systems are established, which are motivated by the multiplicity of paths and products of real biochemical processes in organisms. In order to ensure research universality, core system modeling factors are fully considered. Countable parallel orbits, uniform connection with external sources, countable parallel orbits as subsystems in middle lattices and influences of all lattices on transport trajectories on dynamic properties are analyzed. Dynamic properties of different particles located in orbits are explored by deeply studying average exit time and time scale. Quantitative spatiotemporal impacts are extensively studied. The rationality of average exit time as a time scale in the universal exit dynamic system is proved. Main findings and fruitful results can not only serve as theoretical bases for broadening reaction path modeling, but also be helpful to support understanding nonequilibrium transport mechanisms, especially stochastic biochemical processes. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Artemiprincepsolides A—F (1—6) were isolated from Artemisia princeps guided by bioactivity and elucidated by comprehensive spectral data and ECD calculation. Compounds 1—3 represented the first connecting model of germacrane‐guaiane hetero‐dimeric adducts, and compounds 4—6 were eudesmane‐guaiane hetero‐coupled sesquiterpenoid dimers, meanwhile, all these were presumably formed by Diels‐Alder cycloaddition. Compounds 1—6 were evaluated for their hepatomatic cytotoxicity on three hepatoma cell lines, and demonstrated cytotoxicity with IC50 values in the range of 5.0—67.3 μmol/L. Interestingly, compound 1 manifested significant cytotoxicity against HepG2, Huh7, and SK‐Hep‐1 cells with IC50 values of 9.9, 9.2, and 5.0 μmol/L, which were almost equivalent to the positive control, sorafenib. Flow cytometry data and Western blot assays revealed the most active compound 1 dose‐dependently inhibited cell migration and invasion, and significantly induced HepG2 cells arrest in G2/M phase by downregulating proteins pcdc2 and upregulating the level of protein CyclinB1; and induced apoptosis by downregulating of Bcl‐2 expression and upregulating Bax level. [ABSTRACT FROM AUTHOR]