To a solution of N,N-bis(2-chloroethyl)benzene-1,4-diamine hydrochloride (18, 0.918 g, 3.0 mmol) in dry CHCl3 (35 mL) containing Et3N (0.6 mL) was added dropwise a solution of triphosgene (356 mg, 1.2 mmol.) in an ice bath with vigorous stirring for 30 min. The reaction mixture was evaporated and the residue diluted with THF (20 mL), filtered through a pad of Celite, washed with THF (5 mL). The filtrate containing crude N-mustard isocyanate 19 was evaporated in vacuo to dryness and the residue was dissolved in dry DMF (5 mL) and then added dropwise into the solution of 9-(5-amino-2-methyl-phenylamino)-5-methylacridine-4-carboxylic acid (2-dimethylaminoethyl)amide (0.732 g, 1.7 mmol)33 in dry DMF (25 mL) containing pyridine (2 mL) at −10° C. and then stirred at room temperature for 24 h. The solvent removed under reduced pressure to dryness and the residue was dissolved in a mixture of CHCl3/MeOH containing silica gel (10 gm) and evaporated in vacuo to dryness. The residue was put on the top of a silica gel column (4×30 cm) and chromatographed using CHCl3/MeOH (100:5 v/v) as eluent. The fractions containing the main product were combined and evaporated in vacuo to dryness. The residue was recrystallized from EtOH/hexane to give 9-[5-(3-{4-[bis(2-chloroethyl)amino]phenyl}ureido)-2-methyl-phenylamino]-5-methyl-acridine-4-carboxylic acid (2-dimethylaminoethyl)amide (BO-1053); 0.385 g (32%); mp 286-289° C.; 1H NMR (DMSO-d6) δ 2.19 (3H, s, Me), 2.67 (6H, m, NMe2), 2.85 (3H, s, Me), 3.14 (2H, brs, CH2), 3.63-3.69 (8H, m, 4×CH2), 3.85 (2H, brs, CH2), 6.41 (1H, m, ArH,), 6.65 (2H, d, J=9.0 Hz, ArH), 6.97 (1H, m, ArH), 7.24 (2H, d, J=9.0 Hz, ArH), 7.36-7.44 (1H, m, ArH), 7.51 (1H, m, ArH), 7.74 (2H, m, ArH), 7.93 (1H, m, ArH), 8.09 (1H, m, ArH), 8.41 (1H, m, ArH), 8.67 (1H, m, ArH), 9.04 (1H, brs, exchangeable, NH), 9.45 (1H, brs, exchangeable, NH), 12.18 (1H, brs, exchangeable, NH). Anal. Calcld. for (C37H41Cl2N7O2.6H2O): C, 54.91; H, 5.20; N, 12.34. Found: C, 55.08; H, 5.32; N, 12.44.
