400 mhz dmso d 6 u03b4 13 01 br s 1h 8 93 s 1h 8 71 8 43 m 2h 8 08 d j 7 8 hz 2h 7 41 t j 8 0 hz 2h 7 14 t j 7 4 hz 1h 1 75 1 35 m 3h 0 90 d j 6 3 hz 7h compound 6i can be obtained following procedures described herein 1 h nmr 400 mhz dmso d 6 u03b4 ppm 1 15 t j 7 24 hz 3h 3 08 q j 7 04 hz 2h 7 99 dd j 8 80 2 54 hz 1h 8 24 d j 9 00 hz 1h 8 49 d j 2 35 hz 1h 8 58 s 1h 8 67 br s 1h 8 95 s 1h 13 11 br s 1h compound 7a can be obtained following procedures described herein 1 h nmr 400 mhz dmso d 6 u03b4 9 93 d j 5 1 hz 1h 8 61 8 44 m 1h 8 33 s 1h 8 30 8 09 m 3h 7 36 7 25 m 2h 7 07 6 94 m 1h 3 53 3 44 m 1h 3 14 dd j 6 5.