SYNTHESES OF STABLE BACTERIOCHLOROPHYLL-A DERIVATIVES AS POTENTIAL PHOTOSENSITIZERS FOR PHOTODYNAMIC THERAPY

New methods for conversion of unstable bacteriochlorophyll-a present i n Rb. sphaeroides into stable bacteriochlorins are presented. Cyclic i mide derivatives from related cyclic isoimide or amide analogs are obt ained by intramolecular base catalyzed cyclization. Most of the new ba cteriochlorins have long wavelength absorptions in the range of 796-82 2 nm In preliminary screening, the isoimide analogs have shown promisi ng in vivo photosensitizing activity for the treament of cancer by pho todynamic therapy. Copyright (C) 1996 Elsevier Science Ltd