Abstract
In order to search for a highly potent drug, 1-and 2-pyrimidinylpyrazole derivatives have been examined for analgesic, antipyretic and anti-inflammatory activities. Among the 44 derivatives examined in this series, all of the compounds which are equal to or more potent than aminopyrine in analgesic activity were found to belong to 1-pyrimidinylpyrazole type, while all of 2-pyrimidinylpyrazole derivatives were extremely less active than aminopyrine in analgesic effect. Three compounds which possess a methoxyl group in the 5-position of the pyrazole moiety were found to have especially high potency in this series. It has been found that 1-(4-methoxy-6-methyl-2-pyrimidinyl)-3-methyl-5-methoxypyrazole is the most potent compound having analgesic and anti-inflammatory effects.
