Anticancer properties for 4,4 '-dihydroxybenzophenone-2,4-dinitrophenylhydrazone (A-007)/3,7-diaminophenothiazin-5-ium double salts

4,4'-Dihydroxybenzophenone-2,4-dinitrophenylhydrazone (A-007) formed stable double salts with phenothiazin-5-ium salts (2a-d), which have improved in vitro anticancer activities, as compared to A-007 alone. The stable salt be tween methylene blue (2a) and A-007 allowed the latter to diffuse into the dermis layers of skin. It is anticipated that these new salts will allow A- 007 to penetrate into the deep lymphatic,vascular channels of the dermis, w hich contain metastatic cancer cells, and improve in vivo anticancer activi ties. (C) 2001 Elsevier Science Ltd. All rights reserved.