Antiviral constituents against respiratory viruses from Mikania micrantha.
Phytochemical investigation of the dried aerial parts of Mikania micrantha led to the isolation of a new sesquiterpene, 3beta-acetoxy-1,10-epoxy-4-germacrene-12,8;15,6-diolide (1), along with six known constituents: 1,10-epoxy-4-germacrene-12,8;15,6-diolide (2), dihydromikanolide (3), potassium mikanin 3-sulfate (4), mikanin (5), alpinetin (6), and ergosta-7,22-dien-3beta-ol (7). Their structures were elucidated by spectroscopic methods, and the molecular structures and stereochemistry of sesquiterpene lactones 1-3 were revealed by single-crystal X-ray analysis. Compound 2 showed moderate activity against respiratory syncytial virus (IC(50) = 37.4 uM) and parainfluenza type 3 virus (IC(50) = 37.4 uM) with a therapeutic index (TI) of 16.0 for both compounds. Compound 4, the main component of M. micrantha, exhibited inhibitory activity against parainfluenza type 3 virus with IC(50) (19.7 uM) and TI (24.0) values comparable to those of ribavirin, serving as a positive control.
But
Paul Pui-Hay
PP
Department of Biology and Biochemistry and Institute of Chinese Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, People's Republic of China. paulbut@cuhk.edu.hk
He
Zhen-Dan
ZD
Ma
Shuang-Cheng
SC
Chan
Yiu-Man
YM
Shaw
Pang-Chui
PC
Ye
Wen-Cai
WC
Jiang
Ren-Wang
RW
D000998:Antiviral Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D006723:Hong Kong; D020128:Inhibitory Concentration 50; D035742:Mikania / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010224:Parainfluenza Virus 3, Human / Q000187:drug effects; D012136:Respiratory Syncytial Viruses / Q000187:drug effects; D012254:Ribavirin / Q000494:pharmacology; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D045788:Sesquiterpenes, Germacrane
C550874:3beta-acetoxy-1,10-epoxy-4-germacrene-12,8;15,6-diolide; D000998:Antiviral Agents; D012717:Sesquiterpenes; D045788:Sesquiterpenes, Germacrane; D012254:Ribavirin