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Chiral β-prolines are synthesized and used as organocatalysts in the anti-selective Mannich-type reaction of ketones/aldehydes with ethyl glyoxylate imine.

The intramolecular cyclization of an allyl halide having a carbonyl group proceeded smoothly via an allyl anion in the presence of Me3SiSnBu3 and CsF in DMF. The resultant products were converted into useful compounds for the synthesis of natural products.

A novel 1,3-diene synthetic method from alkyne and ethylene was developed using ruthenium-catalyzed enyne metathesis. The reaction procedure is very simple: A CH 2 Cl 2 solution of alkyne was stirred at room temperature under ethylene gas (1 atm.) in the presence of a catalytic amount of ruthenium benzylidene complex. The yield was good and the conversion yield was high. Dienes having functional groups such as a keto-carbonyl group, silyloxy group, ester, and ketal were synthesized from the corresponding alkynes and ethylene. In this reaction, the alkyne having a hetero atom at the propargylic position gave a good result and ether oxygen or amine nitrogen that coordinate strongly to the ruthenium catalyst prevents the reaction.

A large pseudolumen due to dissection arose during percutaneous coronary angioplasty. The true lumen was compressed critically. However, no infarction took place because of good collaterals. During medical follow-up, the patient's angina vanished suddenly. The repeat angiography showed healing of the dissection and patency of the coronary artery.