Junbiao Chang

Synthesis and biological activity of n-butylphthalide derivatives.

A series of n-butylphthalide derivatives were designed and synthesized. The in vitro activities of these compounds were evaluated by a resting tension of isolated rat thoracic aorta ring assay. Compounds 4g and 4i were found to be more active than n-butylphthalide.

Formation of N-alkoxyindole framework: intramolecular heterocyclization of 3-alkoxyimino-2-arylalkylnitriles mediated by ferric chloride.

A variety of functionalized N-alkoxyindole-3-carbonitrile derivatives are achieved under remarkably mild conditions by applying a FeCl3-mediated intramolecular heterocyclization of 3-alkoxyimino-2-arylalkylnitriles. This novel synthesis allows the N-moiety on the side chain to be annulated to the benzene ring as the final synthetic step, which enables the functionalization of the benzenoid portion of the indole at an early stage of the synthesis.

Design and Synthesis of 3′-Deoxy-3′-Fluoro-2′-O,3′-C-Vinylene-Linked ­BicyclicPurine Nucleoside

Starting from D-xylose via a 3-deoxy-3a-C-ethynyl-3-fluoro sugar as a key intermediate, a novel fluorinated bicyclic purine nucleoside has been synthesized. A neighboring-group participation pathway and a mechanism involving an intramolecular cycloaddition induced by fluorine are proposed for the formation of the key intermediate and the bicyclic nucleoside, respectively.