Synthesis of Methyl 2-((Dimethylcarbamothioyl)oxy)-5-(N-phenylsulfamoyl)benzoate

The solution of methyl 2-((dimethylcarbamothioyl)oxy)-5-(N-phenylsulfamoyl)benzoate (I2) (117 mg, 0.30 mmol) in NMP (2 mL) was heated for 2 hours under argon atmosphere at 210°C. After completion of the reaction as monitored by TLC, reaction mixture was cooled to rt and EtOAc (10 mL) was added, followed by sat. NaCl aqueous solution (20 mL). Organic layer was washed with water, dried over Na₂SO₄, and concentrated under reduced pressure. The reaction mixture was purified by chromatography (silica gel, 50/50 v/v petrolether/EtOAc) to give product (45 mg, 39% yield). ¹H NMR (400 MHz, CDCl₃) δ 8.27 (dd, J = 2.1, 0.5 Hz, 1H), 7.75 (dd, J = 8.3, 2.1 Hz, 1H), 7.70 (dd, J = 8.2, 0.5 Hz, 1H), 7.28–7.21 (m, 2H), 7.17–7.10 (m, 1H), 7.10–7.03 (m, 2H), 3.88 (s, 3H), 3.13 (bs, 3H), 3.03 (bs, 3H). LC-MS: m/z calculated for C₁₇H₁₉N₂O₅S₂ [M+ H⁺]: 395; found 395.