of scheme b a solution of aqueous hydroxylamine 0 5 ml of a 50 aqueous solution 7 6 mmol in water 1 ml and thf 5 ml was cooled to u2212 5 u00b0 c 2 bromo 5 dimethyl 4 carbonyl benzene sulfonyl chloride was added portionwise maintaining a temperature below about 10 u00b0 c and the reaction mixture was stirred at this temperature until complete consumption of the sulfonyl chloride is observed by thin layer chromatography tlc the resulting suspension is concentrated to remove any volatiles and resulting solid was washed with diethyl ether to yield the title compound as a cream solid 0 36 g 36 u03b4h 500 mhz dmso d6 10 00 1h br s 9 88 1h s 7 95 1h d 1 8 hz 7 93 1h d 8 1 hz 7 61 1h dd 8 3 2 0 hz 3 00 3h s 2 91 3h s tr 1 19 min using the experimental conditions reported above and detailed in general synthesis scheme a and b methods 1 and 2 and the appropriate starting materials which were either commercially available or synthesised using standard literature conditions the following derivatives were prepared method of n hydroxy compound systematic sulfonamide no name 1 h nmr t r synthesis yield 3 4 chloro 3 u03b4 h 400 mhz dmso 1 24 a 25 hydroxysulfamoyl 13 62 1h br s 10 03 1h d benzoic acid 2 9 hz 9 88 1h d 2 9 hz 8 50.