A new isomaneonene derivative from the red alga Laurencia cf. mariannensis

Abstract

Determining the structures of new natural products from marine species not only enriches our understanding of the diverse chemistry of these species, but can also lead to the discovery of compounds with novel and/or important biological activities. Herein, we describe the isolation of isomaneonene C (1), a new halogenated C₁₅ acetogenin, and three known compounds, α-snyderol (2), cis-maneonene D (3), and isomaneonene B (4), from the organic extract obtained from the red alga Laurencia cf. mariannensis collected from Iheya Island, Okinawa, Japan. The structures of these secondary metabolites were elucidated spectroscopically. All compounds were inactive at 30 μg/disc against methicillin-resistant Staphylococcus aureus (MRSA) in combination treatment with a β-lactam drug, meropenem.

Graphical Abstract

Keywords:

• Halogenated secondary metabolites
• C₁₅ acetogenin
• maneonene
• Rhodomelaceae
• Laurencia

Acknowledgements

We are grateful to Distinguished Emeritus Professor Satoshi Ōmura (Kitasato University) for his helpful support and valuable guidance and suggestions. We would like to thank Dr. Norio Kikuchi and Dr. Minoru Suzuki (Coastal Branch of the Natural History Museum and Institute, Chiba) for specimen identification. We would also like to thank Editage (www.editage.com) for English language editing.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research was funded by Okinawan Create Leading Projects in Growing Fields 2017-2019, Okinawa Prefectural Government.