| abstract |
The present invention relates to a fused aminodihydrothiazine derivative of formula (I): wherein X is hydrogen or fluorine; A is CH or N; Y is methyl, ethyl, monofluoromethyl, difluoromethyl, trifluoromethyl, difluoroethyl, methoxy, ethoxy, methoxymethyl or -C≡N; and pharmaceutically acceptable salts thereof; which compound has an Αβ production inhibitory effect or a BACEl inhibitory effect and is useful as a prophylactic or therapeutic agent for a neurodegenerative disease caused by Αβ and typified by Alzheimer-type dementia. |