Isolation and Structural Determination of a Complete Set of Intact Bacteriochlorophyll-d Homologs and Isomers from Green Sulfur Bacterium Chlorobium vibrioforme and Their Aggregation Properties in Hydrophobic Solvents

Eight intact bacteriochlorophyll (BChl)-d homologs and isomers were isolated from a strain of green sulfur bacterium Chlorobium vibrioforme. All the molecular structures of the BChl-d components were fully determined by a combination of mass spectrometry and $^1$H-NMR spectroscopy. The aggregation behavior of the isomerically pure BChls-d in hydrophobic organic solvents was examined with respect to the stereoisomeric configuration at the C3$^1$ position as well as the bulkiness of the C8 and C12 side-chains by using electronic- absorption spectroscopy.