1 H NMR ( 300 MHz , DMSO - d 6 ) δ 1 . 61 - 1 . 80 ( 3 H , m ) , 1 . 86 - 2 . 08 ( 1 H , m ) , 2 . 25 ( 3 H , s ) , 3 . 22 - 3 . 29 ( 2 H , m ) , 3 . 37 - 3 . 54 ( 2 H , m ) , 3 . 64 - 3 . 91 ( 5 H , m ) , 6 . 91 - 7 . 20 ( 8 H , m ) .