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Glucose-, galactose- and lactose-containing photosensitizers 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 demetalation. 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 β-D-lactose was obtained and shown to become water-soluble after unblocking of the lactose hydroxy functions. NMR studies allowed for the elucidation of structure, tautomeric form and conformation of the obtained compounds.

The synthesis of derivatives bearing glucose or galactose units linked by an acrylate spacer to one free meso position of a bis-aryl-porphyrin macrocycle was developed and characterized by standard spectroscopic techniques. The new mono-substituted gluco- and galacto-porphyrin derivatives 5–8 present an alternative to the widespread tetra-aryl porphyrin functionalization. Singlet oxygen studies showed a comparable singlet oxygen production with TPP. Furthermore, the less bulky architectures here synthesized present an opportunity to enhance the PDT and PDI capabilities of glycoporphyrins with a simple synthetic modification at one of the meso positions.

The sun is the only source of renewable energy available to us, if geothermal energy is not taken into account. In the form of radiation (UV light, visible light, infrared light, Section 1.1) it sends us annually 178,000 terawatts (1 TW = 10¹² W; unit of power 1 W = 1 J s^–1 = 859.85 calories per hour), that is to say 15,000 times the energy consumed annually by humanity. Only 0.1% of the solar energy received by planet Earth is converted into plant biomass, i.e. 100 × 10⁹ tons per year which corresponds to ca. 180 × 10⁹ tons per year of CO₂ captured from the atmosphere. This CO₂ returns to the biosphere after the death of the plants. Consumption of fossil carbon emits ca. 35 × 10⁹ tons of CO₂ yearly. Biomass is the material produced by all living organisms (plants, animals, microorganisms, fungi)…