Synthesis of amino-analogs of bacteriochlorophyll-d and their self-aggregation in an aqueous micelle solution

Abstract

Zinc methyl 3-aminomethyl- and 3-(1-aminoethyl)-pyropheophorbides-a were prepared by modifying naturally occurring chlorophyll-a. The synthetic amino-analogs of bacteriochlorophyll-d self-aggregated in an aqueous micelle solution to give large oligomers with red-shifted and broadened electronic absorption bands. The spectra of these self-aggregates were similar to those of bacteriochlorophyll self-aggregates in the main light-harvesting antennas of green photosynthetic bacteria. The 3(1)-amino groups were alternative to the 3(1)-hydroxy groups in natural bacteriochlorophylls-c/d/e/f.

Keywords: Chlorosome; J-aggregate; Light-harvesting antenna; Photosynthesis.