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Updated: Jun 24, 2025

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Determination of N-centered stereochemistry in N22-methylated chlorophyll-a derivatives and their epimer-dependent
Riko Ataka1, Tohru Taniguchi2, Kenji Monde2
1Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan.
Abstract:
An N-centered epimeric mixture of chlorophyll-a derivatives methylated at the inner nitrogen atom was separated by reverse-phase high-performance liquid chromatography. Circular dichroism (CD) spectroscopic analyses of the epimerically pure N22-methyl-chlorins revealed that the minor first-eluted and major second-eluted stereoisomers were (22S)- and (22R)-configurations, respectively. Their visible absorption and CD spectra in solution were dependent on the N22-stereochemistry. The epimer-dependent spectral changes were independent of the substituents at the peripheral 3-position of the core chlorin chromophore.
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