1 H NMR ( 400 MHz , DMSO - d 6 ) δ [ ppm ] = 1 . 39 - 1 . 55 ( m , 2 H ) , 1 . 57 - 1 . 67 ( m , 1 H ) , 1 . 67 - 1 . 76 ( m , 1 H ) , 1 . 77 - 1 . 87 ( m , 1 H ) , 2 . 03 - 2 . 14 ( m , 1 H ) , 3 . 90 - 3 . 97 ( m , 1 H ) , 3 . 98 - 4 . 06 ( m , 1 H ) , 4 . 95 ( d , 1 H ) , 7 . 51 ( d , 2 H ) , 7 . 63 ( dd , 1 H ) , 8 . 09 - 8 . 13 ( m , 2 H ) , 8 . 14 - 8 . 19 ( m , 1 H ) , 8 . 66 ( s , 1 H ) , 8 . 69 ( d , 1 H ) , 8 . 91 ( d , 1 H ) , 9 . 31 ( d , 1 H ) .