1,2-Dihydro-4-(6-iodohexyloxy)-1,2-dioxonaphthalene → 2'-[4-[6-(1,2-Dihydro-1,2-dioxo-naphth-4-yl)oxyhexyl]oxyphenyl]-5-(4-methylpiperazin-1-yl)-2,5'-bi-1h-benzimidazole

Participants

Reaction Steps

Hoechst 33258 (3.0 g, 5 mmol) was dissolved in a hot mixture of isopropanol-water (24 mL/12 mL) and neutralized with ammonium hydroxide (3 mL). The precipitate was filtered, triturated with Et2O and dried in vacuo to obtain the free base of bisbenzimidazole. A 1.0 M solution of Bu4NOH in MeOH (0.6 mL, 0.6 mmol) was added to the solution of bisbenzimidazole (1.635 g, 3.85 mmol) in MeOH (30 mL), stirred for 15 min and concentrated to dryness in vacuo. Iodonaphthoquinone 5 (1.485 g, 3.87 mmol) in DMF (30 mL) was added to the tetrabutyl ammonium salt and the mixture was stirred for 48 h. The reaction mixture was suspended in H2O, the crude product was filtered, washed with H2O, dried and purified by flash chromatography (MeOH/CHCl3 1:9, 1:5) to afford 14 as a yellow solid (790 mg, 30%). 1H NMR (CDCl3/MeOH-d4) 8.21 (s, 1H), 8.09 (d, J=7.6 Hz, 1H), 8.05 (d, J=8.7 Hz, 2H), 7.85-7.95 (m, 2H), 7.48-7.75 (m, 4H), 7.14 (bs, 1H), 7.10-6.98 (m 3H), 4.21 (t, J=6.3 Hz, 2H), 4.08 (t, J=6.2 Hz, 2H), 2.65-2.75 (m, 4H), 2.40 (s, 3H), 1.80-2.15 (m, 4H), 1.60-1.75 (m, 4H). MS (LSIMS, 3-NBA) 725.2 (M++1).

Provenance & Evidence