The enduring legacy of Koji Nakanishi's research on bioorganic chemistry and natural products. Part 1: Isolation, structure determination and mode of action

Abstract

In this brief review on Koji Nakanishi's remarkable career in natural products chemistry, we have highlighted a number of his accomplishments that illustrate the broad diversity of his interests. These include the isolation, structure determination, and biological mechanism of action of many natural products including the triterpenoid pristimerin; the diterpenoid ginkgolides; insect and crustacean molting hormones; phytoalexins; the toxic red tide principle brevetoxin; the vanadium tunicate pigments; philanthotoxin from killer wasps; antisickling agents; mitomycin DNA adducts; insect antifeedants; a mitotic hormone, the small molecule fish attractants from the sea anemone; new isolation and purification technologies; molecular chemistry of vision; age‐related macular degeneration; and the development of the exciton circular dichroism (CD) chirality method for microscale determination of absolute configuration of natural products and chirality of other chiral molecules and supramolecular assembly.

The enduring legacy of Koji Nakanishi's research on natural products and bioorganic chemistry. Part 2. Inception and establishment of the ECD exciton chirality method in 1960s to 1970s: A marvel of Nakanishi's Japanese team

“…The dibenzoate chirality rule has been successfully applied to various natural products to determine their absolute configurations (ACs). For example, the AC of ponasterone A, phytoecdysteroid, discussed in the part 1 paper was assigned by applying the rule to the derivative 3 with the help of M. Koreeda, who first isolated ponasterone A (Figure ). The cis A/B ring junction and 2β,3β‐diol configuration leads to a negative chirality, which agrees with the observed CD data …”

“…In the Sendai time (1963–1969), Prof Nakanishi focused on the research of bioactive natural products chemistry . In addition, he was also interested in the spectroscopy for determining the structure of organic compounds, ie, IR, 1 H NMR, ORD (optical rotatory dispersion), and CD.…”