1 H NMR ( 300 MHz , DMSO - d 6 ) δ 1 . 13 ( 6 H , s ) , 1 . 63 - 1 . 86 ( 3 H , m ) , 1 . 88 - 2 . 05 ( 3 H , m ) , 2 . 94 ( 2 H , t , J = 6 . 0 Hz ) , 3 . 17 - 3 . 27 ( 2 H , m ) , 3 . 41 - 3 . 63 ( 2 H , m ) , 3 . 70 - 3 . 96 ( 3 H , m ) , 7 . 19 - 7 . 33 ( 1 H , m ) , 7 . 33 - 7 . 45 ( 1 H , m ) , 7 . 71 ( 1 H , d , J = 1 . 9 Hz ) .