Katsuya Tagami

Syntheses and evaluation of quinoline derivatives as novel retinoic acid receptor α antagonists

In the course of studies on novel retinoids, we have designed and synthesized a series of quinoline derivatives. One of them, 4-[5-[8-(1-methylethyl)-4-phenyl-2-quinolinyl]-1H-2-pyrrolyl]benzoic acid (12f) shows potent RARalpha-selective antagonistic activity.

Novel and Efficient Chromium(II)-Mediated Desulfonylation of α-Sulfonyl Ketone

A novel and efficient method for the Cr(II)-mediated desulfonylation of α-sulfonyl ketone by a Cr-ligand-Mn system has been developed during the course of process research on Halaven (eribulin mesylate). This reaction is dramatically accelerated in the presence of an appropriate bipyridyl-type ligand. This system is applicable to reduction of α-sulfur-substituted ketones. In addition, a Cr-Cp2ZrCl2-Mn catalytic system is also applicable to desulfonylation of α-sulfonyl ketone.

Syntheses and evaluation of naphthalenyl- and chromenyl-pyrrolyl-benzoic acids as potent and selective retinoic acid receptor α agonists

Synthesis and structure activity relationships (SAR) of RAR alpha-selective agonists are discussed. 4-[5-(5,8-Dimethyl-2H-3-chromenyl)-1H-2-pyrrolyl]benzoic acid (12a), which possesses a flat structural moiety and an oxygen atom at the hydrophobic part, showed highly selective transactivation activity at the RAR alpha receptor.