Synthesis, spectroscopy, and photocytotoxicity of glycosylated amino acid porphyrin derivatives as promising molecules for cancer phototherapy

To obtain molecules that can target malignant cells, two series of new meso glucosylporphyrins bearing amino acid residues are synthesized in four ste ps. The first series contained n meso glycosyl moieties and (4 - n) alanyl groups on the ortho or para positions of the meso phenyl. In the second ser ies, the carbohydrate moiety is separated from the aryl substituent by a se rine unit. Starting from p- or o-nitrobenzaldehyde, p- or o-acetylbenzaldeh yde or -tolualdehyde, and pyrrole, the glycosylnitrophenylporphyrins 3-6 an d tritolylporphyrins 8a,b are synthesized under optimized conditions tailor ed from Lindsey's method. The nitro function is then reduced and N-Fmoc-L-a lanine or acetylglycosylated N-Fmoc-serine are coupled on the amino functio n. A detailed H-1 and C-13 NMR study allows complete structural elucidation . The UV-visible fluorescence and MALDI mass spectra are presented. Compoun ds 19-22 produced O-1(2), and photocytotoxicities against the K562 leukemia cell line are compared to hematoporphyrin. As a result of their sensitizin g abilities, these resultant compounds are of considerable interest for pho todynamic therapy.