ABSTRACT
Eight labdane diterpenoids, including two new labdane diterpenoids, named forsyshiyanins A-B (2-3), along with six known ones (1, 4-8), were isolated from the fruits of Forsythia suspensa. The new structures including their absolute configurations were elucidated by extensive spectroscopic analyses, X-ray diffraction and computational calculation. In vitro, eight labdane diterpenoids showed anti-inflammatory activities, with the inhibition rates of release of ß-glucuronidase from polymorphonuclear leukocytes of rats being in the range 46.8-51.0% at concentrations of 10 µM, as well as anti-viral activities against influenza A (H1N1) virus and respiratory syncytial virus (RSV), with the IC50 values in the range 18.4-26.2 µM and EC50 values in the range 10.5-14.4 µM, respectively.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Antiviral Agents/pharmacology , Diterpenes/pharmacology , Forsythia/chemistry , Animals , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/isolation & purification , Antiviral Agents/chemistry , Antiviral Agents/isolation & purification , Crystallography, X-Ray , Diterpenes/chemistry , Diterpenes/isolation & purification , Dogs , Fruit/chemistry , Hep G2 Cells , Humans , Influenza A Virus, H1N1 Subtype/drug effects , Influenza, Human/drug therapy , Madin Darby Canine Kidney Cells , Models, Molecular , Rats , Respiratory Syncytial Virus Infections/drug therapy , Respiratory Syncytial Viruses/drug effectsABSTRACT
Five previously undescribed labdane diterpenoids, named Forsypensins A-E, were isolated from the fruits of Forsythia suspensa. The structures and relative configurations of the compounds were elucidated via extensive spectroscopic methods, and their absolute configurations were fully confirmed by single crystal X-ray diffraction analyses using Cu Kα radiation and electronic circular dichroism data. The five labdane diterpenoids showed in vitro anti-inflammatory activity in rat polymorphonuclear leukocytes, inhibiting the rates of ß-glucuronidase release by 43.6%-49.2% at concentrations of 10 µM. The compounds also had anti-viral activity against influenza A (H1N1) virus and respiratory syncytial virus (RSV), with IC50 values in the range 21.8-27.4 µM, and EC50 values in the range 10.5-15.4 µM, respectively.
Subject(s)
Diterpenes , Forsythia , Influenza A Virus, H1N1 Subtype , Animals , Anti-Inflammatory Agents , Molecular Structure , RatsABSTRACT
Four undescribed flavonoid alkaloids, as two pairs of enantiomers, were initially isolated as a racemate from the whole plant of Scutellaria moniliorrhiza. By means of chiral HPLC, four isomers, named scumonilines A-D, were successfully separated, and their chemical structures including absolute configurations were established by mass as well as NMR spectroscopy and CD technique. In vitro, four flavonoid alkaloids showed anti-inflammatory activities, with IC50 values against the release of ß-glucuronidase from polymorphonuclear leukocytes of rats being in the range 5.16-5.85 µΜ. Moreover, four compounds were evaluated for their inhibitory activities against aldose reductase, and gave IC50 values in the range 2.29-3.03 µΜ.
Subject(s)
Aldehyde Reductase/antagonists & inhibitors , Alkaloids/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Enzyme Inhibitors/pharmacology , Flavonoids/pharmacology , Scutellaria/chemistry , Aldehyde Reductase/metabolism , Alkaloids/chemistry , Alkaloids/isolation & purification , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/isolation & purification , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/isolation & purification , Flavonoids/chemistry , Flavonoids/isolation & purification , Glucuronidase/antagonists & inhibitors , Glucuronidase/metabolism , Humans , Molecular Structure , Neutrophils/drug effects , Neutrophils/metabolism , Rats , Structure-Activity RelationshipABSTRACT
Two new flavonoid glucuronate esters, named scuregeliosides A and B (1 and 2), as well as three known ones, chrysin-7-O-ß-d-glucuronic acid methyl ester (3), 5,7,4'-trihydroxyflavone-8-O-ß-d-glucuronic acid methyl ester (4) and apigenin-7-O-ß-d-glucuronic acid ethyl ester (5), were isolated from the ethanolic extract of the whole plant of Scutellaria regeliana. Their chemical structures were elucidated on the basis of comprehensive spectroscopic analyses. Five compounds were screened for anti-inflammatory activity in vitro. As the results, the inhibition rates of release of ß-glucuronidase from rat polymorphonuclear leukocytes were in the range of 42.2 - 47.1% at a concentration of 10 µm.
