| abstract |
The invention relates to compounds of the general formula n nin which R 1 , R 2 , R3, R 4 , R 2′ , R3′, R 4′ , R 5 , and X is —CHR— are as defined in the specification. The invention also provides pharmaceutically acceptable acid addition salts, optically pure enantiomers, racemates and diastereomeric mixtures of such compounds. The invention further provides methods for the treatment of Alzheimer's disease or common cancers. |