aM.V. Lomonosov Academy of Fine Chemical Technology, Moscow, Russia
bN.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia
Journal of Porphyrins and Phtalocyanins, 2009, v.13(3), pp. 336-345
Glucose-, galactose- and lactose-containing photosensibilizers based on derivatives of chlorophyll a and bacteriochlorophyll a were synthesized with the use of [3+2] cycloaddition between sugar azides and triple bond derivatives of chlorins and bacteriochlorins. Unlike bacteriochlorin cycloimide, chlorin was detected to form a Cu-complex during the click reaction. An approach to the synthesis of metal-free glycosylated chlorins was developed with the use of "protection" by Zn2+ cation and subsequent demetallization. It is based on the action of alkynyl chlorin e6 derivative Zn-complex, which is resistant to the substitution by copper cation. Bacteriochlorin p cycloimide conjugate with per-acetylated b-D-lactose was obtained and shown to become water soluble after unblocking of the lactose hydroxy functions. The thorough NMR studies allowed the elucidation of structure, tautomeric form and conformation of the obtained compounds.