Structurally Diverse Polymethylated Phloroglucinol Meroterpenoids from Baeckea frutescens

Yin-E Zhi; Xu-Jie Qi; Hui Liu; Yuan Zeng; Wei Ni; Li He; Zu-Ding Wang; Hai-Yang Liu

doi:10.1007/s13659-018-0189-3

Structurally Diverse Polymethylated Phloroglucinol Meroterpenoids from Baeckea frutescens

Nat Prod Bioprospect. 2018 Dec;8(6):431-439. doi: 10.1007/s13659-018-0189-3. Epub 2018 Oct 29.

Authors

Yin-E Zhi¹, Xu-Jie Qi¹, Hui Liu¹, Yuan Zeng¹, Wei Ni¹, Li He², Zu-Ding Wang³, Hai-Yang Liu⁴

Affiliations

¹ State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, and Yunnan Key Laboratory of Medicinal Chemistry, Kunming, 650201, China.
² Department of Dermatology, The First Affiliated Hospital of Kunming Medical University, Kunming, 650032, China.
³ Kunming Botanee Bio-Technique Co. Ltd, Kunming, 650106, China.
⁴ State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, and Yunnan Key Laboratory of Medicinal Chemistry, Kunming, 650201, China. haiyangliu@mail.kib.ac.cn.

Abstract

Phytochemical investigation of the MeOH extract of twigs and leaves of Baeckea frutescens led to the isolation of seven new polymethylated phloroglucinol meroterpenoids (PPMs), named baeckfrutones M-S (1-7). Their structures and absolute configurations were determined by spectroscopic analyses, chiral-phase HPLC analysis, and electronic circular dichroism (ECD) calculations. PPM 1 is a novel meroterpenoid possessing a 6/6/5/3 tetracyclic skeleton in PPMs, whereas 3 and 4 are the first hydroxytasmanone type phloroglucinol-monoterpene hybrids. (+)-2 and 7 displayed potent anti-inflammatory activity with IC₅₀ values of 20.86 ± 0.60 and 36.21 ± 1.18 μΜ, respectively.

Keywords: Anti-inflammatory activity; Baeckea frutescens; Myrtaceae; Polymethylated phloroglucinol meroterpenoids.

Abstract

Grants and funding