New benzimidazoles as thrombopoietin receptor agonists

A novel benzimidazole series of small-molecule thrombopoietin receptor agonists has been discovered. Herein, we discuss the preliminary exploration of structure-activity relationships within this chemotype.

[New reactivities of nitrogen-containing aromatics and their synthetic application]

This review describes new knowledge on reactivities and syntheses of N-containing aromatics and their application to the synthesis of natural products covering three subjects. 1) The first part describes the Fischer indole synthesis of o-substituted phenylhydrazones, its mechanism, Reissert indole synthesis, a new synthetic approach from pyrrole to indole, some reactions of indoles (i.e., etc.), acylation, bromination, debromination, debenzylation, Vilsmeier-Haack reaction, and synthesis of 4-methoxy-beta-carboline alkaloids. 2) The second part describes a new method of introduction of allyl and vinyl groups on the indole nucleus by means of a Pd catalyst. This method was applied to the synthesis of optically active ergot alkaloids. 3) The third part describes the synthesis of o-substituted diacylanilines and its application to chemoselective acylating reagents. A study on axial chirality based on the Ar-N axis is also involved.