Antiviral and anti-inflammatory activities of chemical constituents from twigs of Mosla chinensis Maxim.

Seven undescribed compounds, including three flavones (1-3), one phenylpropanoid (19), three monoaromatic hydrocarbons (27-29), were isolated from the twigs of Mosla chinensis Maxim together with twenty-eight known compounds. The structures were characterized by HRESIMS, 1D and 2D NMR, and ECD spectroscopic techniques. Compound 20 displayed the most significant activity against A/WSN/33/2009 (H1N1) virus (IC50 = 20.47 µM) compared to the positive control oseltamivir (IC50 = 6.85 µM). Further research on the anti-influenza mechanism showed that compound 20 could bind to H1N1 virus surface antigen HA1 and inhibit the early attachment stage of the virus. Furthermore, compounds 9, 22, 23, and 25 displayed moderate inhibitory effects on the NO expression in LPS inducing Raw 264.7 cells with IC50 values of 22.78, 20.47, 27.66, and 30.14 µM, respectively.

Four undescribed triterpenes from the aerial parts of Verbena officinalis.

Verbena officinalis is used as a Chinese folk medicine for the treatment of rheumatism and bronchitis. Herein, four undescribed triterpenes, officinalisoids A-D (1-4), together with thirty-three known compounds (5-37) were isolated from the aerial parts of V. officinalis. The chemical structures of the new compounds were determined by spectrometric data interpretation using NMR, HRESIMS, IR and UV spectroscopy. Biological evaluation results revealed that compound 30 exhibited potential anti-inflammatory activity with IC50 value of 6.07 µM (CC50 > 50 µM) and compound 12 showed moderate anti-dengue virus activity with the IC50 value of 24.55 µM (CC50 > 50 µM).

A new prenylated 3-benzoxepin derivative with anti-influenza A virus activity from Elsholtzia penduliflora.

A new prenylated 3-benzoxepin derivative, elsholtzioxin (1), together with fifteen known compounds (2-16) were isolated from the whole parts of Elsholtzia penduliflora. Their structures were elucidated on the basis of various spectroscopic techniques and chemical evidences. The antiviral activities of these compounds were evaluated in vitro. The new compound (1) exhibited potential anti-influenza virus activity against strain A/WSN/33/2009 (H1N1) with inhibition rate of 47.19%. Compounds 2, 9 and 12 exhibited significant inhibitory activities with IC50 value of 26.16, 34.66 and 20.81 µM, respectively.

Bodiniosides S-Y, Seven New Triterpenoid Saponins from Elsholtzia bodinieri and Their Anti-Influenza Activities.

Investigation of the n-BuOH extract of the aerial parts of Elsholtzia bodinieri led to the isolation of seven new triterpenoid saponins, Bodiniosides S-Y (1-7, resp.). Their strictures were elucidated on the basis of spectroscopic techniques, including HSQC, HSBC, and HSQC-TOCSY experiments, together with acid hydrolysis and GC analysis. The anti-influenza activities of compounds 1-7 were evaluated against A/WSN/33/2009 (H1N1) virus in MDCK cells. The results showed that compounds 2 and 5 exhibited moderate anti-influenza activities against A/WSN/33/2009 (H1N1), with inhibition rates of 35.33% and 24.08%, respectively.

Two new oleanane triterpenoid saponins from Elsholtzia bodinieri.

Two new oleanane triterpenoid saponins, bodiniosides Q (1) and R (2), along with five known saponins, niga-ichigoside F1 (3), 3-O-[ß-D-glucopyranosyl]-28-O-[α-L-rhamnopyranosyl -(1→2)-ß-D-glucopyranosyl] arjunolic acid (4), asiaticoside E (5), sericoside (6), and bodinioside E (7), were isolated from the aerial parts of Elsholtzia bodinieri. The structures of 1 and 2 were characterized by spectroscopic techniques and chemical evidence as 3-O-ß-D- xylopyranosyl-2α, 23-dihydroxy-olean-12-en-28-oic acid 28-O-α-L-rhamnopyranosyl- (1→2)-ß-D-glucopyranoside (1) and 3-O-ß-D-xylopyranosyl-2α, 23-dihydroxy-olean-12-en-28-oic acid 28-O-[ß-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl -(1→2)]-ß-D-glucopyranoside (2). Compounds 1, 3, and 5 exhibited weak anti-influenza activity against strain A/WSN/33/2009 (H1N1), with inhibition rate of 11.63%, 17.01%, and 16.98%, respectively.

Design, synthesis and biological evaluation of amino acids-oleanolic acid conjugates as influenza virus inhibitors.

Viral entry inhibitors are of great importance in current efforts to develop a new generation of anti-influenza drugs. Inspired by the discovery of a series of pentacyclic triterpene derivatives as entry inhibitors targeting the HA protein of influenza virus, we designed and synthesized 32 oleanolic acid (OA) analogues in this study by conjugating different amino acids to the 28-COOH of OA. The antiviral activity of these compounds was evaluated in vitro. Some of these compounds revealed impressive anti-influenza potencies against influenza A/WSN/33 (H1N1) virus. Among them, compound 15a exhibited robust potency and broad antiviral spectrum with IC50 values at the low-micromolar level against four different influenza strains. Hemagglutination inhibition (HI) assay and docking experiment indicated that these OA analogues may act in the same way as their parent compound by interrupting the interaction between HA protein of influenza virus and the host cell sialic acid receptor via binding to HA, thus blocking viral entry.

Ursane-type triterpenoid saponins from Elsholtzia bodinieri.

Investigation of the n-BuOH extract of the aerial parts of Elsholtzia bodinieri led to the isolation of two new ursane-type triterpenoid saponins, bodiniosides O (1) and P (2), along with five known saponins, rotungenoside (3), 3,28-O-bis-ß-d-glucopyranosides of 19α-hydroxyarjunolic acid (4), oblonganosides I (5), rotungenic acid 28-O-α-L-rhamnopyranosyl-(1→2)-ß-d-glucopyranoside (6), and bodinioside M (7) isolated from the species. The structures of compounds 1 and 2 were characterized by spectroscopic data as well as acid hydrolysis and GC analysis as 3-O-ß-d-xylopyranosyl-23-acetoxy-urs-12(13)-en-28-oic acid 28-O-ß-d-xylopyranosyl-(1→6)-[ß-d-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→2)]-ß-d-glucopyranoside and 3-O-ß-d-xylopyranosyl-23-hydroxy-urs-12(13)-en-28-oic acid 28-O-ß-d-glucopyranosyl-(1→6)-ß-d-glucopyranoside. Compounds 1 and 2 exhibited potent anti-HCV activities in vitro with a selective index of 30.63 and 9.08, respectively.

Two new ursane-type triterpenoid saponins from Elsholtzia bodinieri.

Two new ursane-type triterpenoid saponins, bodiniosides M (1) and N (2), along with three known saponins, oblonganosides I (3), pseudobuxussaponin B (4) and bodinioside A (5), were isolated from the aerial parts of Elsholtzia bodinieri. The structures of compounds 1 and 2 were characterized by spectroscopic data as well as acid hydrolysis and GC analysis as 3-O-ß-D-xylopyranosyl-19α-hydroxy-23-acetoxy-urs-12(13)-en-28-oic acid 28-O-α-L-rhamnopyranosyl-(1-2)-ß-D-glucopyranoside and 3-O-ß-D-glucopyranosyl-2α,19α-dihydroxy-urs-12(13)-en-28,20ß-lactone. Compounds 1 and 5 exhibited potent anti-HCV activities in vitro with a selective index of 6.53 and 4.41, respectively.

A new flavonoid glycoside from Elsholtzia bodinieri.

A new flavonoid glycoside, eriodictyol 7-O-(6″-caffeoyl)-ß-D-glucopyranoside (1), along with 14 known compounds, were isolated from the whole plants of Elsholtzia bodinieri. All of the structures were determined by spectroscopic methods and chemical transformation. Compound 1 and luteolin (9) exhibited potent anti-HCV activities with a selective index of 135.85 and 20.84, respectively.

Antioxidant phenolic glycoside and flavonoids from Pieris japonica.

A new phenolic glycoside, benzyl 2-hydroxy-4-O-ß-D-glucopyranosyl-benzoate (1), along with nine known flavonoids, epicatechin-(2 → O → 7,4 → 8)-ent-epicatechin (2), bis-8,8'-catechinylmethane (3), quercetin (4), quercetin-3-O-α-L-arabinfuranoside (5), quercetin-3-O-α-L-rhamnopyranoside (6), astilbin (7), engeletin (8), (2S,3R)-ent-catechin (9), and 2',4-dihydroxy-4'-methoxy-6'-O-ß-D-glucopyranosyl dihydrochalcone (10), was isolated from the flowers of Pieris japonica. Their structures were elucidated on the basis of MS, 1D NMR, and 2D NMR techniques. This paper describes the isolation, structural elucidation as well as in vitro antioxidant activity of these compounds.

Two new grayanane diterpenoids from the flowers of Rhododendron molle.

A phytochemical investigation of the flowers of Rhododendron molle has yielded two new grayanane diterpenoids, rhodomolleins F and G (1, 2). Compounds 1 and 2 possessed an oxo-bridge between C-5 and C-9, and their structures were elucidated on the basis of interpretation of spectroscopic data, including 1D and 2D NMR techniques.