NEW MATERIAL:The pyrazolone derivative of formula I and/or formula II [R1 is cycloalkyl, (substituted) aryl or heterocyclic group; R2 is H or alkyl; R3 is heterocyclic group; n is 0 or 1].
EXAMPLE: 1-Phenyl-3-(3-pyridyl)-2-pyrazolin-5-one.
USE: A lipid peroxide-formation inhibiting agent useful as a preventive or remedy for various ischemic diseases, various cerebral diseases, cardiac diseases or peripheral circulation disorder. It is administered at a rate of 1W100mg per dose and 1W3 doses a day by oral administration, 0.01W10mg per dose and 2W5 doses a day by intravenous injection or 1W100mg per dose and 1W3 doses a day by rectal infusion.
PREPARATION: A β-keto acid derivative of formula III (R4 is 1W5C alkyl) is made to react with a hydrazine derivative of formula H2NNH-R1 at 10W200°C optionally in the presence of a solvent such as methanol and a catalyst such as a base.
NISHI HIROYOSHI
WATANABE TOSHIAKI
YUKI TOSHIYUKI
SAKURAI YOKO
HAYASHI YOSHIO
FUKUSHIMA NOBUKO