[Cl:1][C:2]1[C:3]([CH3:21])=[N:4][S:5][C:6]=1[NH:7][C:8](=[O:20])[CH2:9][C:10]1[CH:15]=[CH:14][C:13]([OH:16])=[C:12]([N+:17]([O-])=O)[CH:11]=1>[Pt].CN(C)C=O>[Cl:1][C:2]1[C:3]([CH3:21])=[N:4][S:5][C:6]=1[NH:7][C:8](=[O:20])[CH2:9][C:10]1[CH:15]=[CH:14][C:13]([OH:16])=[C:12]([NH2:17])[CH:11]=1N-(4-Chloro-3-methyl-5-isothiazolyl)-4-hydroxy-3-nitrophenylacetamide (50 g, 0.15 mol), 1% w/w platinum on carbon (15 g) and N,N-dimethylformamide (400 ml) were charged to a 600 ml stainless steel hydrogenation vessel. Once purged the vessel was pressurised to 35 bar with hydrogen, stirring was started and the reaction was heated to 35° C. After 6 hours the uptake of hydrogen had stopped; the stirring and heating were turned off and the mixture was allowed to cool to ambient temperature. The vessel was vented, purged with nitrogen and was heated to 50° C. to ensure complete solution. The reaction mixture was filtered to remove the catalyst and the liquors concentrated under high vacuum to remove the N,N-dimethylformamide. The resultant residue was slurried in dichloromethane (300 ml), filtered, washed with dichlorometane (200 ml) and dried to give give N-(4-chloro-3-methyl-5-isothiazolyl)-3-amino-4-hydroxy-phenylacetamide (43.9 g) as a buff solid, m.p. 239-243° C.
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