1 H NMR ( 300 MHz , DMSO - d 6 ) δ 1 . 66 - 1 . 82 ( 3 H , m ) , 1 . 85 - 2 . 07 ( 4 H , m ) , 3 . 22 - 3 . 29 ( 2 H , m ) , 3 . 38 - 3 . 57 ( 2 H , m ) , 3 . 72 - 3 . 91 ( 3 H , m ) , 6 . 99 ( 2 H , d , J = 8 . 7 Hz ) , 7 . 11 ( 1 H , d , J = 8 . 3 Hz ) , 7 . 18 - 7 . 27 ( 3 H , m ) , 7 . 33 ( 1 H , d , J = 7 . 5 Hz ) , 7 . 45 - 7 . 55 ( 1 H , m ) .