Catalytic Atroposelective Synthesis of Axially Chiral Heterobiaryl Oxime Ethers via the One-Step Dynamic Kinetic Condensation Reaction.

The catalytic atroposelective synthesis of axially chiral heterobiaryls was first developed through the direct one-step dynamic kinetic condensation reaction with the simple transformation of the C═O bond to the C═N bond, delivering a series of novel axially chiral heterobiaryl oxime ethers.

Ag2O-Induced Regioselective Huisgen Cycloaddition for the Synthesis of Fully Substituted Pyrazoles as Potential Anticancer Agents.

Efficient regioselective synthesis of novel fully substituted pyrazoles has been achieved through Huisgen cycloaddition reaction of δ-acetoxy allenoates with hydrazonoyl chlorides by the addition of Ag2O. The present approach offers the advantages of simpleness, high efficiency, mild conditions, wide substrate scope, and good-to-excellent regioselectivities. The strategy could be performed on a large-scale pattern to allow access to structurally versatile pyrazoles, of which a key intermediate of lonazolac (303), a nonsteroidal anti-inflammatory drug, could be synthesized efficiently. Moreover, several pyrazoles show obvious growth-inhibitory activity of Huh-7 cells, expected as potential anticancer agents.