Reaction Steps
A mixture of 1-(5-bromopentyl)-3-n-pentylurea (100 mg, 0.37 mmol), commercial N-(4-hydroxybenzo[d]thiazol-2-yl)acetamide (100 mg, 0.48 mmol), and K2CO3 (67 mg, 0.48 mmol) in DMF (5 mL) was heated at 60° C. After 6 h, the reaction mixture was cooled to rt, diluted with water (25 mL), and extracted into EtOAc (3×10 mL). The combined organic extracts were washed with water (2×5 mL), brine (10 mL), dried (Na2SO4) and concentrated in vacuo. The residue thus obtained was purified by silica gel column chromatography to give 31 (61 mg, 40%), mp 61.6-61.8° C. TLC: EtOAc/hexane (3:2), Rf˜0.40; 1H NMR (300 MHz) δ 7.39 (dd, J=0.9, 7.3 Hz, 1H), 7.20 (dd, J=7.8, 7.3 Hz, 1H), 6.86 (dd, J=0.9, 7.8 Hz, 1H), 4.42 (br s, —NH, 2H), 4.17 (t, J=5.4 Hz, 2H), 3.19-3.30 (m, 4H), 2.33 (s, 3H), 1.82-1.98 (m, 2H), 1.64-1.80 (m, 4H), 1.42-1.60 (m, 2H), 1.24-1.40 (m, 4H), 0.88 (t, J=7.3 Hz, 3H); 13C NMR (75 MHz) δ 170.16, 159.91, 158.94, 151.37, 139.10, 133.67, 124.40, 113.94, 108.68, 68.21, 40.64, 39.98, 30.27, 29.30, 28.33, 26.54, 23.25, 22.64, 22.33, 14.26. HRMS (ESI-neg) calcd for C20H29N4O3S [M−1]− 405.1960. found 405.1938.
