Biokinetic investigation of the photodynamic activity of new photosensitizers

Abstract

Results of an in vivo biokinetic investigation of the photodynamic activity of a series of new photosensitizers including a tetraazachlorin derivative (2,3,3α,21α-tetrahydro-2-methyl-3α,8,13,18-tetraphenyl-5,10,15,20-tetraaza-1H,22H,24H-pyrrolo[3, 4-b]porphine), two difluoroboryl-substituted complexes of 3,3′-diphenylazadiisoindolylmethene {N,N-difluoroboryl-N-[3-(4-t-butylphenyl)-2H-isoindol-1-yl)]-N-[3-(4-t-butylphenyl)-1H-isoindol-1-yliden]amine and N,N-difluoroboryl-1-[3-(4-methoxyphenyl)-2H-isoindol-1-yl)]-N-[3-(4-methoxyphenyl)-1H-isoindol-1-yliden]amine}, and a sulfanyl-substituted phthalocyanine [1,8,15,22-tetrakis(t-butylsulfanyl)-29H, 31H-phthalocyanine] are reported. These compounds exhibit pronounced photodynamic activity in mice bearing solid Ehrlich ascites carcinoma and sarcoma S-37 upon intravenous injection as micellar suspensions in aqueous solutions (4%) of Cremophor EL and Proxanol 268. Acomparison of the tumor growth rate and the time of attaining a critical tumor volume in the test and control groups shows evidence for high photodynamic activity of the new photosensitizers.