abstract |
The present invention provides a compound of the following formula or a pharmaceutically acceptable salt thereof: [Chemical 1] (Where X is [Chemical 2] Selected from the group consisting of R is selected from the group consisting of H and CH 3 ; R1 is H, CH 3 , F, Cl, OCH 3 , C (O) OH, C (O) NH 2 , and Selected from the group consisting of: [Selection figure] None |