b sulphonyl chloride 10 mg 17 u03bcmol conjugable daa1106 10 mg 20 u03bcmol and tri ethylamine 15 u03bcl in dichloromethane 1 6 ml was stirred under argon at room temperature for 1 hour the reaction solution was concentrated by rotary evaporation and the crude product was purified through column chromatography silica gel using a 19 1 dichloromethane methanol solution to yield lissdaa as pink solid isomer i 5 7 mg 32 isomer ii 4 7 mg 27 1h nmr 400 mhz cdcl3 isomer i u03b4 8 84 s 1h 7 98 d j 7 6 hz 1h 7 30 7 24 m 3h 7 19 d j 7 6 hz 1h 7 08 t j 7 2 hz 1h 6 93 6 90 m 2h 6 78 t j 8 8 hz 3h 6 70 dd j 8 4 2 0 hz 1h 6 66 6 63 m 3h 6 37 d j 8 4 hz 1h 6 19 s 1h 5 61 t j 5 2 hz 1h 4 78 d j 6 4 hz 1h 3 59 s 3h 3 56 3 45 m 7h 3 10 q j 6 4 hz 2h 3 02 2 96 m 1h 2 87 2 81 m 1h 2 01 s 2h 1 72 1 50 m 12h 1 44 1 37 m 4h 1 21 t j 6 8 hz 3h isomer ii u03b4 8 72 s 1h 8 36 d j 7 2 hz 1h 7 27 7 18 m 5h 7 08 t j 7 6 hz 1h 6 95 6 89 m 2h.