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Elucidation of the Relationship between CD Cotton Effects and the Absolute Configuration of Sixteen Stereoisomers of Spiroheterocyclic-Lactams.

ABSTRACT: As part of research to search for antitumor agents in fungi originating from marine organisms, cephalimysins E?L were isolated from a culture broth of Aspergillus fumigatus that was separated from the marine fish Mugil cephalus. One- and two-dimensional nuclear magnetic resonance spectra revealed their planar structures, which are diastereomers of each other. Their absolute stereostructures were established by epimerization at C-8 with acidic methanol, nuclear Overhauser effect spectroscopy (NOESY), and circular dichroism (CD) spectroscopy. These demonstrated the detailed relationships between absolute configuration and CD Cotton effects. Additionally, in the growth inhibition assay against P388, HL-60, L1210, and KB cell lines, some of the fungal metabolites or reaction products exhibited moderate activities.

SUBMITTER: Yamada T

PROVIDER: S-EPMC6071047 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Elucidation of the Relationship between CD Cotton Effects and the Absolute Configuration of Sixteen Stereoisomers of Spiroheterocyclic-Lactams.

Yamada Takeshi T Kajimoto Tetsuya T Kikuchi Takashi T Tanaka Reiko R

Marine drugs 20180629 7

As part of research to search for antitumor agents in fungi originating from marine organisms, cephalimysins E⁻L were isolated from a culture broth of <i>Aspergillus fumigatus</i> that was separated from the marine fish <i>Mugil cephalus</i>. One- and two-dimensional nuclear magnetic resonance spectra revealed their planar structures, which are diastereomers of each other. Their absolute stereostructures were established by epimerization at C-8 with acidic methanol, nuclear Overhauser effect spe ...[more]

PMID: 29966281

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