[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([C:24]#N)[C:12]2[S:16][C:15]([NH:17][C:18]([NH:20][CH2:21][CH3:22])=[O:19])=[N:14][C:13]=2[CH:23]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(O)=[O:27]>O.[Al].[Ni]>[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([CH:24]=[O:27])[C:12]2[S:16][C:15]([NH:17][C:18]([NH:20][CH2:21][CH3:22])=[O:19])=[N:14][C:13]=2[CH:23]=1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=11-(5-(Benzyloxy)-7-cyanobenzo[d]thiazol-2-yl)-3-ethylurea (1.00 g, 2.84 mmol) was stirred in formic acid (75 ml) and water (20 ml). Aluminum Nickel alloy (5.5 g, 64.7 mmol) was added and the reaction was stirred at 95° C. for 5 h under N2. LCMS indicated 60% conversion to the desired aldehyde. The reaction was allowed to cool then the volatiles were removed under reduced pressure. The resulting concentrated solution was neutralized to pH9 with a 2M aqueous solution of sodium hydroxide then extracted with EtOAc, the combined extracts concentrated and the resulting residue purified by column chromatography eluting with EtOAc 50 to 100% in petroleum-ether to afford the aldehyde as a yellow solid (200 mg, 99% purity by LC-MS) (20%).
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