[N+:1]([O-:4])([OH:3])=[O:2].C(OC(=O)C)(=O)C.O[CH2:13][CH2:14][C:15]1[S:19][C:18]([NH:20][C:21](=[O:28])[C:22]2[CH:27]=[CH:26][CH:25]=[N:24][CH:23]=2)=[N:17][C:16]=1[CH3:29].C([O-])(O)=O.[Na+].C(=O)=O>>[CH3:29][C:16]1[N:17]=[C:18]([NH:20][C:21](=[O:28])[C:22]2[CH:27]=[CH:26][CH:25]=[N:24][CH:23]=2)[S:19][C:15]=1[CH2:14][CH2:13][O:2][N+:1]([O-:4])=[O:3]70% nitric acid (1.2 ml) was added to acetic anhydride (5 ml) while stirring and maintaining the temperature between 20-30° C. by external cooling. The mixture was cooled to −5° C. while stirring, followed by the addition of 1 gram of N-[5-(2-hydroxy-ethyl)-4-methyl-thiazol-2-yl]-nicotinamide. After 30 minutes at −5° C. the mixture was heated to 10° C. and stirred for one additional hour. The resulting mixture was poured into ice-water and stirred for 1 hour. Aliquots of NaHCO3 were added until CO2 evolution ceased. The orange-yellow water solution was extracted with three portions of 15 ml ethyl acetate. The combined extracts were dried over sodium sulfate and concentrated by evaporation.
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