Two new germacrane sesquiterpenoids from the inflorescences of Mikania micrantha. (April 2023)

• Record Type: Journal Article
• Authors: Lou, Tao; Xu, Qiao-Lin; Tan, Yu-Ling; Liu, Shao-Bo; Zhang, Shan-Xuan; Zeng, Ying; Jiang, Feng-Qiang; Tan, Jian-Wen
• Is Part Of: Phytochemistry letters. Volume 54(2023)
• Page Start: 141
• Page End: 145
• Publication Date: 2023-04
• Subjects: Mikania micrantha -- Inflorescence -- Germacrane -- Sesquiterpenoid -- Antibacterial activity; Botanical chemistry -- Periodicals; Chimie végétale -- Périodiques; 572.205
• DOI: 10.1016/j.phytol.2023.02.010
• Languages: English
• ISSNs: 1874-3900

Abstract

Abstract: Two new germacrane sesquiterpenoids, 3 β -hydroxyl-11 β, 13-dihydrodeoxymikanolide (1 ) and 2 β, 3 β -dihydroxyl-13-methoxy-11 β, 13-dihydrodeoxymikanolide (2 ), together with four known ones (3 –6 ) were isolated from the inflorescences of Mikania micrantha . Their structures were elucidated on the basis of extensive spectroscopic analysis including 1D, 2D NMR and MS techniques. All the compounds were obtained from the inflorescences of M. micrantha for the first time. These compounds were tested for their in vitro antibacterial activity against Gram-positive bacteria of Staphyloccocus aureus, methicillin-resistant Staphylococcus aureus, Bacillus cereus and Bacillus subtilis, and the Gram-negative bacterium of Escherichia coli . Compounds 5 and 6 were found to show strong or moderate in vitro antibacterial activity toward all the tested bacteria with MIC values ranging from 6.25 to 12.5 µg/mL. Graphical Abstract: ga1 Highlights: Two new germacrane sesquiterpenoids (1 and 2 ) were isolated from inflorescences of Mikania micrantha . Four known compounds (3 −6 ) were also obtained from M. micrantha for the first time. The structures of the isolated compounds were elucidated by spectroscopic means. Compounds 5 and 6 showed strong or moderate in vitro antibacterial activity.