(7-Iodo-1,1-dioxo-1,4-dihydro-1λ6-benzo[1,2,4]thiadiazin-3-yl)-acetic acid (prepared as described in Example 24b, 2.62 g, 7.16 mmol) was dissolved in anhydrous N,N-dimethylformamide (30 mL). 2-(4-Fluoro-benzylamino)-cyclohexanecarboxylic acid ethyl ester (2.0 g, 7.16 mmol) was added followed by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1.44 g, 7.52 mmol). Then N-methylmorpholine (1.52 g, 15.04 mmol) was added into the above reaction mixture. The mixture stirred at 25° C. for 24 h. The solution was diluted with ethyl acetate (200 mL), washed with 1.0 M aqueous hydrochloric acid solution, saturated aqueous sodium bicarbonate solution and saturated aqueous brine solution. The organic layer was dried over sodium sulfate and concentrated in vacuo to afford the crude product, 2-{(4-fluoro-benzyl)-[2-(7-iodo-1,1-dioxo-1,4-dihydro-1λ6-benzo[1,2,4]thiadiazin-3-yl)-acetyl]-amino}-cyclohexanecarboxylic acid ethyl ester, as a yellow oil, which was used directly in the next step without further purification. LC-MS (ESI) calcd for C25H27FIN3O5S 627.07, found 628.3 [M+H+].
