Structurally diverse diterpenoids from the leaves of Croton mangelong and their anti-diabetic activity.

Eighteen compounds including eleven previously undescribed diterpenes were isolated from the leaves of Croton mangelong. The structures were determined by HRESIMS, IR, NMR, X-ray diffraction and ECD spectroscopic analysis. All isolates were assayed for their anti-hyperglycemic activities in insulin resistance (IR) 3T3-L1 adipocytes, and compound 4 was tested for its anti-diabetic activity in vivo. Results suggested compound 4 could effectively reduce blood glucose level in diabetic SD rats in a dose of 30 mg/kg.

In Vitro Hypoglycemic Diterpenoids from the Roots of Croton yunnanensis.

Fifteen compounds including nine new diterpenes were isolated from the roots of Croton yunnanensis. By HRESIMS, NMR, ECD data, and X-ray diffraction analysis, the new compounds were characterized as eight neo-clerodane diterpenes (compounds 1-8) and one 15,16-dinor-ent-pimarane diterpene (9). All diterpenes were assayed for their hypoglycemic activities. Compounds 1-4, 6, 7, and 10 promoted glucose uptake activity in insulin-resistant 3T3-L1 adipocytes. Compounds 1 and 6 showed insulin sensitizing activity, potentiating conspicuously their glucose uptake activity at a concentration of 20 µM when treated synergistically with low-concentration insulin at 1 nM.

Two new bis-diterpenoid alkaloids from Aconitum weixiense.

Further investigation on the roots of Aconitum weixiense led to the isolation of two new bis-diterpenoid alkaloids, named as weisaconitines E and F (1-2), which were elucidated by IR, HR-ESI-MS, 1D- and 2D-NMR analyses. Their structures are characterized as denudatine-atisine-type bis-diterpenoid alkaloids.

Tigliane Diterpenoids with Larvicidal, Antifungal, and α-Glucosidase Inhibitory Activities from Croton damayeshu.

Thirty-five tigliane diterpenoids and two ent-kaurane diterpenoids were isolated from the leaves of Croton damayeshu, and, among them, compounds 1-10 were characterized as new tigliane diterpenoids. The structures of compounds 1-10 were determined by analysis of their HRESIMS, NMR, and ECD data and by chemical methods. The isolates were assayed for their larvicidal, antifungal, and α-glucosidase inhibitory activities, and compounds 8-10 were found to possess larvicidal activities against Plutella xylostella with LC50 values of 0.19, 0.16, and 0.26 µM, respectively, comparable to the LC50 of 0.14 µM for the positive control, flubendiamide.

Bioactive constituents from Salacia cochinchinensis.

Two new isopimarane diterpenoids, named 1α-hydroxy-7-oxoisopimara-8, 15-diene (1), 11ß-hydroxy-7-oxoisopimara-8(14), 15-diene (2), together with six known compounds (3-8), were isolated from the medicinal plant Salacia cochinchinensis. All isolates were assayed for their cytotoxicity and α-glucosidase inhibitory activity. Results suggested compounds 1, 3 possessed significant cytotoxic activity against HepG2, HL60, and Hela cell lines with IC50 values ranging from 0.23 to 0.35 µM, and compounds 7, 8 exhibited noticeable α-glucosidase inhibitory ability with IC50 values of 0.25 and 0.31 µM, respectively.

Bioactive glycosides from Salacia cochinchinensis.

Four new triterpene glycosides, named salaciacochinosides A-D (1-4) were isolated from the 90% ethanol extract of Salacia cochinchinensis, together with five known compounds 2α,3ß,23-trihydroxyurs-12,18-dien-28-oic acid 28-O-ß-d-glucopyranoside (5), racemiside (6), alangiplatanoside (7), acantrifoside E (8), and syringin (9). The structures of the four new triterpenoids were characterized by chemical methods and MS, IR, 1D and 2D NMR spectral analyses. The α-glucosidase inhibitory activities of the nine compounds were assessed, compounds 6 and 7 showed remarkable α-glucosidase inhibitory activities, with IC50 values of 0.44 and 0.75 µM, respectively. Compounds 1-5 exhibited moderate α-glucosidase inhibitory activities, and compounds 8 and 9 showed none α-glucosidase inhibitory activity in our current experiments.

Two novel terpenoids from the cultured Perovskia atriplicifolia.

Two new terpenoids, named biperovskatone B (1) and 1α- hydroxyl demethylsalvicanol quinine (2), were isolated from the cultured Perovskia atriplicifolia. Their structures were elucidated by comprehensive analyses of the MS, IR, 1D and 2D NMR spectra. Compound 1 was a novel diterpenoid dimer, containing two different rearranged 9(10 → 20)-abeoabietane type diterpenoid fragments. Compound 2 was a new icetexane diterpenoid with characteristic ortho-quinone carbonyl groups. Both compounds were assayed for their anti-HBV activity in vitro. Results suggested compounds 1 and 2 showed noticeable anti- anti-HBV activity, inhibiting the replication of HBV DNA with IC50 values of 10.78 and 8.61 µM, respectively.

[Study on Chemical Constituents of Peanut Hull].

OBJECTIVE: To investigate the chemical constituents of peanut hull. METHODS: Several chromatography methods such as silica gel and Sephadex LH-20 combined with recrystallization were applied to isolate the compounds. Based on spectrum technologies (MS,1H-NMR and 13C-NMR) and physico-chemical methods, structures of isolated compounds were identified. RESULTS: Twelve compounds were isolated and elucidated as luteolin (1), diosmetin (2), 5,7,3',4'-tetrahydroxy-8-prenyflavone (3),5,7,3'-trihydroxy-4'- methoxy-8-prenylflavone(4), eriodicrtyol (5), racemoflavone (6), hydnocarpin (7), 5,7-dihydroxy chromone (8), 5-hydroxy-chromone- 7-O-ß-D-glucoside (9), ferulic acid (10), ß-sitosterol (11) and daucosterol(12). CONCLUSION: Except compounds 1, 5 and 8, all compounds are obtained from peanut hull for the first time.

[Chemical constituents from aerial part of Aconitum brachypodum].

OBJECTIVE: To study the chemical constituents from the aerial part of Aconitum brachypodum. METHODS: The constituents were isolated and purified by silica gel, activated alumina and Sephadex LH-20 column chromatography. their structures were elucidated on the basis of spectral data and physiochemical evidence. RESULTS: Eleven compounds were isolated from 80% ethanol extract and identified as secokaraconitine (1), brachyaconitines A (2), C (3), talatisamine (4), hypaconitine (5), songrine (6), bullatine A (7), 7-carbony sitosterone (8), lupeol (9), ß-sitosterol (10) and daucosterol (11). CONCLUSION: All compounds are isolated from the aerial part of Aconitum brachypodum for the first time.

[Akaloids from roots of Stephania dentifolia].

Eight alkaloids were isolated from the thin sulfuric acid extracts of the fresh roots of Stephania dentifolia by aluminum oxide, silica and Sephadex LH-20 column chromatography methods. Based on the spectroscopic analysis and chemical evidence, the structures of these alkaloids were identified as sinoacutine (1), sinomenine (2), cephamonine (3), tetrahydropalmatine (4), capaurine (5), stepharanine (6), (+)-stepharine (7) and palmatine (8). All compounds were obtained from this plant for the first time.

[Chemical constituents of Aconitum brachypodum from Dong-Chuan area].

Aconitum brachypodum is traditionally known to be toxic chinese medicie, but its chemical constituents is not enough studied to date. To further elucidate the chemical constituents of A. brachypodum, 80% ethanol extract of A. brachypodum collected from Dong-Chuan area was investigated, which led to isolation of seventeen compounds. By spectroscopic methods, their structures were determined as hypaconitine (1), mesaconitine (2), talatisamine (3), neoline (4), fuziline (5), aconine (6), bullatine A (7), lepeine (8), songrine (9), isocorydine (10), beta-sitosterol (11), daucosterol (12), stearic acid (13), triacontanol (14), palmitic acid (15), benzoic acid (16), and inosine (17), respectively. All compounds except for compounds 1 and 7 were isolated from A. brachypodum for the first time.

Two new triterpenoid glycosides from Curculigo orchioides.

Two new cycloartane triterpenoid glycosides, named curculigosaponin N and curculigosaponin O, were isolated from rhizomes of Curculigo orchioides Gaertn. Their structures were elucidated on the basis of comprehensive spectroscopic analysis including IR, MS, 1D, and 2D NMR (HSQC and HMBC).

Anti-hepatitis B virus active lactones from the traditional Chinese herb: Swertia mileensis.

Swerilactones H-K (1-4), which are four novel lactones with an unprecedented C29 skeleton, were isolated from Swertia mileensis (Qing-Ye-Dan), an endemic Chinese herb used for treating viral hepatitis. Their structures were determined by extensive spectroscopic and X-ray crystallographic diffraction analyses. Swerilactones H-K exhibit potent anti-hepatitis B virus activity against HBV DNA replication with IC(50) values ranging from 1.53 to 5.34 µM. For the first time, a plausible biogenetic pathway for swerilactones H-K, together with the previously reported swerilactones A-D is proposed. From a biogenetic point of view, swerilactones A-D are ascribed as secoiridoid dimers, and swerilactones H-K as secoiridoid trimers.

Three new phenolic glycosides from Curculigo orchioides G.

Three new phenolic glycosides, curculigosides F-H (1-3), were isolated from rhizomes of Curculigo orchioides Gaertn. Their structures were elucidated based on comprehensive spectroscopic analyses including IR, MS, 1D- and 2D NMR (HSQC, COSY, and HMBC). Curculigosides F-H (1-3) were evaluated for their anti-HBV activity in vitro using the HBV transfected Hep G2.2.15 cell line. Compound 1 exhibited weak activity with an IC(50) value of 2.08 mM on hepatitis B virus (HBV) e antigen (HBeAg) secretion of the HepG2.2.15 cell line.

Four new trace phenolic glycosides from Curculigo orchioides.

Four new trace phenolic glycosides named orcinosides D (1), E (2), F (3), and G (4) were isolated from the rhizomes of Curculigo orchioides Gaertn. Based on comprehensive spectroscopic analyses including IR, FAB-MS, HR-ESI-MS, 1D- and 2D NMR (HSQC, HMBC), their structures were elucidated as orcinol-1-O-beta-D-xylopyranoside (1), orcinol-1-O-beta-D-apiofuranosyl-(1 --> 2)-beta-D-glucopyranoside (2), orcinol-3-O-beta-D-apiofuranosyl-1-O-beta-D-glucopyranoside (3), and 1-O-beta-D-glucopyranosyl-4-ethoxyl-3-hydroxymethylphenol (4).

Swerilactones C and D, anti-HBV new lactones from a traditional Chinese herb: Swertia mileensis.

Swerilactones C (1) and D (2), two novel diastereomeric lactones with an unprecedented 6/6/6/6/6 pentacyclic ring system, were isolated from the traditional Chinese herb Swertia mileensis. Their structures and relative stereochemistry were elucidated on the basis of spectroscopic methods and further confirmed by X-ray single-crystal diffraction analysis. In vitro antihepatitis B virus (HBV) assay on the Hep G 2.2.15 cell line showed that both compounds 1 and 2 exhibited inhibitory activities against the secretion of HBsAg (IC(50) = 1.24 and 2.96 mM, respectively) and HBeAg (IC(50) = 0.77 and 1.47 mM, respectively).

Swerilactones A and B, anti-HBV new lactones from a tradtional Chinese herb: Swertia mileensis as a treatment for viral hepatitis.

Swerilactones A (1) and B (2), two novel lactones with an unprecedented 6/6/6/6/6 pentacyclic ring system, were isolated from the traditional Chinese herb of Swertia mileensis with activity against the hepatitis virus. Their structures and relative stereochemistry were elucidated based on spectroscopic methods and further confirmed by X-ray single crystal diffraction analysis. In vitro antihepatitis B virus (HBV) assay on Hep G 2.2.15 cell line showed that compound 1 inhibited HBsAg and HBeAg secretion with IC(50) values of 3.66 and 3.58 mM, respectively.