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. 2018 Jun 29;16(7):223.
doi: 10.3390/md16070223.

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

Takeshi Yamada  1 , Tetsuya Kajimoto  2 , Takashi Kikuchi  3 , Reiko Tanaka  4
Affiliations

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

Takeshi Yamada et al. Mar Drugs. .

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.

Keywords: Aspergillus fumigatus; Mugil cephalus; cephalimysins; circular dichroism spectroscopy; cytotoxicity; marine microorganism; spiro-heterocyclic γ-lactam.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Structures of natural products from A. fumigatus.
Figure 2
Figure 2
CD spectra of 1 and 5′.
Figure 3
Figure 3
Key NOESY correlations of 1–4.
Figure 4
Figure 4
The difference of CD spectra of 1–4 twisting clockwise (A) and 5–8 twisting counterclockwise (B) between the carbonyl (C-4) and the enone moiety (C-10–C-12).
See this image and copyright information in PMC

References

    1. Kitano M., Yamada T., Amagata T., Minoura K., Tanaka R., Numata A. Novel pyridinopyrone sesquiterpene type pileotin produced by a sea urchin-derived Aspergillus sp. Tetrahedron Lett. 2012;53:4192–4194. doi: 10.1016/j.tetlet.2012.05.144. - DOI
    1. Yamada T., Mizutani Y., Umebayashi Y., Inno N., Kawashima M., Kikuchi T., Tanaka R. A novel ketoaldehyde decalin derivative, produced by a marine sponge-derived Trichoderma harzianum. Tetrahedron Lett. 2014;55:662–664. doi: 10.1016/j.tetlet.2013.11.107. - DOI
    1. Suzue M., Kikuchi T., Tanaka R., Yamada T. Tandyukisins E and F, novel cytotoxic decalin derivatives isolated from a marine sponge-derived fungus. Tetrahedron Lett. 2016;57:5070–5073. doi: 10.1016/j.tetlet.2016.10.004. - DOI
    1. Yamada T., Suzue M., Arai T., Kikuchi T., Tanaka R. Trichodermanins C–E, new diterpenes with a fused 6-5-6-6 ring system produced by a marine sponge-derived fungus. Mar. Drugs. 2017;15:169. doi: 10.3390/md15060169. - DOI - PMC - PubMed
    1. Yamada T., Kitada H., Kajimoto T., Numata A., Tanaka R. The relationship between the CD Cotton effect and the absolute configuration of FD-838 and its seven stereoisomers. J. Org. Chem. 2010;75:4146–4153. doi: 10.1021/jo100496f. - DOI - PubMed

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