1: 1-bromo-hexane; 2,3,6,7-tetrakis-hexyloxy-1,5-dihydroxy-anthraquinone With potassium hydroxide in dimethyl sulfoxide T=60°C; 24 h; 2: acetic anhydride With pyridine Heating;

1.1: 50 percent / NaOH / dimethylsulfoxide / 18 h / 50 °C 2.1: KOH / dimethylsulfoxide / 24 h / 60 °C 2.2: 40 percent / pyridine / Heating View Scheme

1.1: 50 percent / NaOH / dimethylsulfoxide / 18 h / 50 °C 2.1: KOH / dimethylsulfoxide / 24 h / 60 °C 2.2: 40 percent / pyridine / Heating View Scheme