| abstract |
A composition having BACE 1 inhibitory activity containing a compound represented by the formula (I): n n n n n n n n n n n n wherein ring A is an optionally substituted carbocyclic group or an optionally substituted heterocyclic group; n E is lower alkylene; n X is S, O, or NR 1 ; n R 1 is a hydrogen atom or lower alkyl; n R 2a , R 2b , R 3a , R 3b , R 4a , and R 4b , is each independently a hydrogen atom, halogen, or hydroxyl etc.; n n and m are each independently an integer of 0 to 3; n n+m is an integer of 0 to 3; n R 5 is a hydrogen atom or substituted lower alkyl; n its pharmaceutically acceptable salt or a solvate thereof. |