NAPHTHOTHIOPYRANONE DERIVATIVES

摘要

A naphthothiopyranone derivative represented by the formula: . (wherein R1 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) and an acid addition salt thereof have more excellent antagonist effect at serotonin 3 receptors than the prior art compounds and the effects based thereon, e.g. anti-vomiting effect, gastrointestinal movement regulating effect and anti-anxiety effect.