[SH:1][C:2]1[CH:7]=[CH:6][N:5]=[C:4]([C:8]([O:10]C)=[O:9])[CH:3]=1.O.S.[Na].Br[C:16]1[S:20][C:19]([NH:21][C:22]2[CH:27]=[C:26]([CH3:28])[CH:25]=[CH:24][N:23]=2)=[N:18][CH:17]=1.SC1C=CC=CN=1.C[O-].[Na+].[OH-].[Na+].Cl>CO.O.CN(C=O)C>[CH3:28][C:26]1[CH:25]=[CH:24][N:23]=[C:22]([NH:21][C:19]2[S:20][C:16]([S:1][C:2]3[CH:7]=[CH:6][N:5]=[C:4]([C:8]([OH:10])=[O:9])[CH:3]=3)=[CH:17][N:18]=2)[CH:27]=1A DMF (8 mL) suspension of methyl 4-mercaptopicolinate (1.40 g, 8.16 mmol, prepared as described in Org. Prep. and Proc. Int. vol. 29 no 1, p. 117 (1997)) and sodium hydrogensulfide hydrate (0.685 g, 12.24 mmol, 1.5 eq) was bubbled with argon and heated to 35° C. 5-bromo-N-(4-methylpyridin-2-yl)thiazol-2-amine (1.103 g, 4.08 mmol, 1 eq, described in the synthesis of bromides, Example A) was diluted in methanol (15 mL) and this was treated by the DMF suspension of mercaptopyridine followed by a solution of sodium methoxide (4.6M in methanol, 2.7 mL, 12.24 mmol). The reaction was purged with argon and stirred at 65° C. for 1 hour. The reaction was then concentrated to remove most of the methanol, diluted in ethyl acetate/THF and acidified with 1N HCl. The aqueous phase was extracted with ethyl acetate (3×) but part of the compound remained in the aqueous phase. The two phases were combined and evaporated. The residue was then mixed with aqueous sodium hydroxide (5N, 8 mL, 40.8 mmol) and methanol followed by water were added. The reaction was stirred at 23° C. overnight, then acidified with 1N HCl. Methanol was evaporated and the solid was collected by filtration to give the crude title material (0.812 g, 58%) as a solid which was used as such in the next reaction. LC/MS (M+H)+: 345. HPLC ret. time (Condition B): 1.187 min.
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