A catechin analogue in which the geometry was constrained to be planar was synthesized. The planar catechin showed excellent radical-scavenging ability, comparable to that of quercetin, and efficient protection against DNA strand breakage induced by the Fenton reaction.

The ability of liquid crystalline solvent phases to control the stereochemical course of bimolecular thermal reactions of 2,6-dialkoxyanthracenes with a series of fumarates conducted at 130−180 °C has been examined, primarily with respect to the structural compatibility of the solutes with the solvent mesogens. For the case of the model thermal [4 + 2] cycloadditions of 2,6-bis(decyloxy)anthracene to bis (trans-4-cyclohexylcyclohexyl) and cholesteryl trans-4-cyclohexylcyclohexyl fumarates at 130−150 °C, cholesteryl 2,4-dichlorobenzoate(CDCB) and bis(4-pentyloxyphenyl) trans-1,4-cyclohexanedicarboxylate(BPCD) serve well as cholesteric and smectic liquid crystalline solvents and result in the preferential formation of syn -isomers with an extremely high level of regioselection ( syn / anti ≥ 20/1). In contrast, the isotropic solvents with closely related structures give isomer ratios of only ≥3/1. Structural similarities between the solutes and the solvent mesogens appear to play a key and influential role in controlling the stereochemical course of the reaction. The temperature dependence for the isomer distribution affords an estimate of the differences of solvation enthalpy and entropy between syn and anti transition states in the anisotropic media.

An oxidative methyl esterification of aldehydes was effectively achieved. The trivalent indium reagent, indium(III) triflate, was revealed to accelerate the reactions in many cases. Aromatic aldehydes with various substituents were subjected to this method, and each produced the corresponding methyl esters in good to excellent yields within a relatively short reaction time.

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Indium(III) triflate, a trivalent indium reagent, was shown to be a highly-efficient catalyst for the conversion of primary amides to the corresponding nitriles. The successful reactions required 5 mol% of indium(III) triflate, and toluene was proved to be the most suitable solvent. Various amides were subjected to this method, and each produced the corresponding nitriles in excellent yields.