3-Deacetyl-3-(1-hydroxyethyl)bacteriopyrochlorophyll-a (1), 7,8-dihydrobacteriochlorophyll-d possessing 8-ethyl, 12-methyl and 17⁴-phytyl groups, was prepared by modifying naturally occurring bacteriochlorophyll-a. The synthetic 3¹-epimers were separated by high-performance liquid chromotagraphy, and the absolute configuration at the 3¹-position was determined by derivatization of 1 to a structurally determined chlorin. A dichloromethane solution of 3¹R-1 or 3¹S-1 was diluted with a 1000-fold volume of cyclohexane to give self-aggregation species absorbing light at a near-infrared (NIR) region (<910 nm). The resulting Q_y maximum in 3¹R-1 was 860 nm and redshifted by 2170 cm⁻¹ from the monomeric one, whereas epimeric 3¹S-1 showed a less redshifted peak at ca 800 nm, with a small dimeric band around 740 nm. Such visible spectra indicated that 3¹R/S-1 formed different supramolecular structures in the self-aggregates. In contrast, self-aggregation of the 7,8-dehydro-compound 2, bacteriochlorophyll-d_P, found in natural antennas of photosynthetic green bacteria showed much smaller diastereomeric control. The self-aggregates of 3¹R-1 absorbing light in the NIR region would be models of intrinsic membranous light-harvesting complexes 1 in photosynthetic purple bacteria as well as extramembranous antennas in green bacteria.