Diverse terpenoid glycosides with in vitro cytotoxicity from Glechoma longituba.

Terpenoids are the largest class of all known natural products, possessing structural diversity and numerous biological activities. Ten previously undescribed terpenoid glycosides, glechlongsides A-J (1-10), were isolated from the ethanol extract of the whole plant of Glechoma longituba, including diterpenoid glycoside and pentacyclic triterpenoid saponin. The structures of these compounds were characterized by extensive analysis of 1D and 2D NMR as well as HRESIMS spectra. In addition, glechlongsides F-I (6-9) exhibited weak cytotoxicity against human cancer cell lines BGC-823, Be1, HCT-8, A2780, and A549 with IC50 values ranging from 3.77 to 30.95 µM, respectively.

Four new polyprenylated acylphloroglucinol derivatives from Hypericum beanii.

Two new polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperbeanins P-Q (1-2), and two new biosynthetic precursors, hyperbeanins R-S (3-4), were isolated from Hypericum beanii, together with three known analogs (5-7). Compound 1 was one of type A PPAPs featured with unusual bicyclo[5.3.1]hendecane core. The structures of isolates were established by NMR spectroscopic methods, experimental electronic circular dichroism (ECD) spectra and comparisons with known compounds. Compounds 5 and 6 showed obvious hepatoprotective activity at 10 µM against paracetamol-induced HepG2 cell damage.

[Chemical constituents of triterpenoids from Euphorbia resinifera].

The combination of normal-phase silica gel column chromatography, octadecyl silica(ODS) column chromatography, semi-preparative high performance liquid chromatography(HPLC), etc. was employed to isolate and purify the chemical components from Euphorbia resinifera, and 7 triterpenoids were separated from the ethanol extract of the medicinal materials. Their structures were identified by various spectroscopy methods as cycloartan-1,24-diene-3-one(1), cycloartan-1,24-diene-3-ol(2), 3ß-hydroxy-lanosta-8,24-diene-11-one(3), lnonotusane C(4), eupha-8,24-diene-3ß-ol-7,11-dione(5), eupha-24-methylene-8-ene-3ß-ol-7,11-dione(6), and eupha-8,24-diene-3ß,11ß-diol-7-one(7). Compounds 1 and 2 are new compounds, and compound 3 is obtained from nature for the first time.

[Chemical constituents from Hypericum curvisepalum].

This study explored the chemical constituents of the aerial part of Hypericum curvisepalum. Sixteen compounds were isolated from the 95% ethanol extract of H. curvisepalum with various chromatographic techniques, including a new prenylated phenyl polyketide, mysorenone D(1). Other compounds were mysorenone-A(2), mysorenone-C(3), mysorenone-B(4), peplidiforone A(5), 4-methoxy-3-(2-methylbut-3-en-2-yl)-6-phenyl-2H-pyran-2-one(6), hyperenone-A(7), 4-(3,3-dimethylallyl)oxy-6-phenyl-α-pyrone(8), peplidiforone B(9), elegaphenone(10), hypercohin A(11), hyperisampsin G(12), spathulenol(13), quercetin(14), ß-sitosterol(15), and ß-amyrin(16).

Structural Revision of Hyperibrin B and Hyperscabrones H and I by Biosynthetic Considerations, NMR Analysis, and Chemical Synthesis.

Previously, Gao et al. reported the isolation and structural determination of three natural products, hyperibrin B (HB), hyperscabrone H (HH), and hyperscabrone I (HI), from Hypericum scabrum. HB and HH had different NMR spectroscopic data, but they were assigned identical structures. Furthermore, these compounds should be derived from bicyclic polyprenylated acylphloroglucinols (BPAPs) via degradation, but the assigned structural features of the prenyl and prenylmethyl groups being cis and meta-substituted on the cyclohexanone core were not consistent with their biosynthetic origin. In this note, we revise the structures of HB, HH, and HI via NMR and MS spectroscopic analyses and biosynthetic considerations. We also complete a total synthesis of the revised structure of HB as well as its analogue, hyperibrin A, to further confirm the revision. The revised structures of HB, HH, and HI have not been reported.

Hypseudohenrins I - K: three new polycyclic polyprenylated acylphloroglucinol derivatives from Hypericum pseudohenryi.

Three previously unidentified polycyclic polyprenylated acylphloroglucinols (PPAPs) derivatives, hypseudohenrins I-K (1-3), along with a known analogue hyphenrone X (4), were isolated from the aerial part of Hypericum pseudohenryi. The structures of the new compounds were elucidated by NMR spectroscopy and ECD calculation. The anti-inflammatory activity of the compounds was evaluated. Compounds 1-3 showed mild anti-inflammatory activity while hyphenrone X showed prominent anti-inflammatory activity.[Formula: see text].

Two new polycyclic polyprenylated acylphloroglucinols derivatives from Hypericum acmosepalum.

Polycyclic polyprenylated acylphloroglucinols (PPAPs) were mainly obtained from the plants of Hypericum genus of Guttiferae family, and possessed intriguing chemical structures and appealing biological activities. Two new PPAPs derivatives, hyperacmosin C (1) and hyperacmosin D (2) were isolated from H. acmosepalum. Their structures were established by NMR, HREIMS, and experimental electronic circular dichroism spectra. Besides, compound 1 showed significant hepatoprotective activity at 10 µM against paracetamol-induced HepG2 cell damage and compound 2 could moderately increase the relative glucose consumption.

Hyperacmosins H-J, three new polycyclic polyprenylated acylphloroglucinol derivatives from Hypericum acmosepalum.

Three new polycyclic polyprenylated acylphloroglucinol derivatives, hyperacmosins H-J (1-3), with four known compounds (4-7), were isolated from the air-dried aerial parts of Hypericum acmosepalum. Especially, compounds 1 and 2 were identified as methylated polycyclic polyprenylated acylphloroglucinol derivatives (mPPAPs). Their structures were established by NMR, HRESIMS and experimental electronic circular dichroism (ECD) spectra. The hepatoprotective activity of seven compounds were evaluated. Compounds 1 and 5 exhibited hepatoprotective activity against paracetamol-induced HepG2 cell damage.[Formula: see text].

Hyperascyrins L - N, rare methylated polycyclic polyprenylated acylphloroglucinol derivatives from Hypericum ascyron.

Seven natural compounds, including new compounds hyperascyrins L-N (1-3) and four known compounds (4-7), were acquired from the aerial parts of Hypericum ascyron, that were all identified as methylated polycyclic polyprenylated acylphloroglucinol derivatives (mPPAPs). The structures of these compounds were established by NMR spectroscopy, experimental and calculated electronic circular dichroism (ECD) data. The neuroprotective activities and hepatoprotective activity of these compounds (10 µM) were evaluated. Compounds 1, 2 and 3 exhibited neuroprotection activity. Compounds 1 and 3 show hepatoprotective activity.

Methylated Polycyclic Polyprenylated Acylphloroglucinol Derivatives from Hypericum ascyron.

Hyperascyrins A-H (1-11) and four known compounds (12-15) were acquired from the air-dried aerial parts of Hypericum ascyron and were all identified as methylated polycyclic polyprenylated acylphloroglucinol derivatives. Their structures were established by NMR spectroscopy, experimental and calculated electronic circular dichroism (ECD) data, and comparison with established compounds. Compounds 8 and 9 showed protection against paracetamol-induced HepG2 cell damage at 10 µM. The neuroprotective activities of all compounds (10 µM) were evaluated, and compounds 1 and 8 exhibited mild neuroprotection against glutamate-induced toxicity in SK-N-SH cells.

[Chemical constituents of Hypericum perforatum].

A chemical investigation on the aerial parts of Hypericum perforatum resulted in the isolation of a new phloroglucinol derivatives (1), and seven known compounds (2-8). The structures of the compounds were elucidated by means of spectroscopic methods (MS, IR, 1D NMR, and 2D NMR) as 3-methyl-4,6-di (3- methyl-2-butenyl)-3-(4-methyl-3-pentenyl)-2-(2-ethyl-1-oxobutyl)-cyclohexanone (1)，hyperforin (2)，(2R,3R,4S,6R)-3-methyl-4,6-di(3-methyl-2-butenyl)-2-(2-methyl-1-oxo-propyl)-3-(4-methyl-3-pentenyl)-cyclohexanone (3)，hyperscabrin B (4)，hyperscabrin C (5)，furohyperforin isomer 1 (6)，furoadhyperforin (7)，and furohyperforin (8). Compound 1 was a new compound, and compounds 3-5 were obtained from H. perforatum for the first time.

Polyisoprenylated benzoylphloroglucinol derivatives from Hypericum scabrum.

Four new polyisoprenylated benzoylphloroglucinol derivatives, hyperscabrones J-M (1-4), were isolated from the air-dried aerial parts of Hypericum scabrum. Their structures were elucidated by spectroscopic methods and were subsequently confirmed by comparing with data of known compounds. The absolute configuration of the bicyclo[3.3.1]nonane-2,4,9-trione core was defined by the experimental and calculated electronic circular dichroism (ECD) spectra. The evaluation of their hepatoprotective activities against paracetamol-induced HepG2 cell damage showed that compounds 2 and 4 exhibited significant hepatoprotection at 10µM.

Polycyclic Polyprenylated Acylphloroglucinol Congeners from Hypericum scabrum.

Twenty polycyclic polyprenylated acylphloroglucinols (PPAPs), including the new compounds hyperscabrones A-I (1-9), were isolated from the air-dried aerial parts of Hypericum scabrum. These compounds comprise seven different structural types. All structures were determined by NMR spectroscopic methods and both experimental and calculated electronic circular dichroism (ECD) spectra. The evaluation of their neuroprotective effects on glutamate-induced toxicity in SK-N-SH cells showed that compounds 4-7 exhibited significant neuroprotection at 10 µM. Additionally, compounds 3, 4, 7, and 9 showed moderate hepatoprotective activities against paracetamol-induced HepG2 cell damage at 10 µM.

Hepatoprotective triterpenes from the gum resin of Boswellia carterii.

Ten tirucallane-type triterpenes named boscartene A-J and a nor-tetracyclic triterpene boscartene K, together with ten known compounds were isolated from the gum resin of Boswellia carterii Birdw. Their structures and absolute configurations were elucidated by extensive spectroscopic analysis. In vitro assay, some of these compounds (10 µM) showed moderate hepatoprotective activities against d-galactosamine-induced HL-7702 cell damage.

Alkenes with antioxidative activities from Murraya koenigii (L.) Spreng.

Four new alkenes (1-4), and six known alkenes (5-12) were isolated from Murraya koenigii (L.) Spreng. Their structures were elucidated on the basis of spectroscopic analyses and references. Compounds (1-12) were evaluated for antioxidative activities. Among them, compounds 1, 2, 4, and 7 exhibited significant antioxidative activities using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay with IC50=21.4-49.5 µM. The known compounds (5-12) were isolated from this plant for the first time.

[Chemical constituents of Myripnois dioica].

To study the chemical constituents of the aerial parts of Myripnois dioica. Twelve compounds were separated from the 95% ethanol extract of M. dioica by using various chromatographic techniques. Their stuctures were identified on the basis of their physicochemical properties and spectral data as 8-desoxyurospermal A(1), zaluzanin C(2), dehydrozaluzanin C(3), glucozaluzanin C(4), macrocliniside B(5), macrocliniside I(6), taraxinic acid-14-O-ß-D-glucopyranoside(7), ainsliaside B(8), apigenin(9), luteolin(10), apigenin-7-O-ß-D-glucopyranoside(11), and luteolin-7-O-ß-D-glucopyranoside(12). Except for compound 8, the other compounds were isolated from this genus for the first time. Compound 8 was found to decrease blood glucose level properly in alloxan-induced diabetic mice.

Effect of Hypericum perforatum L. extract on insulin resistance and lipid metabolic disorder in high-fat-diet induced obese mice.

Natural product Hypericum perforatum L. has been used in folk medicine to improve mental performance. However, the effect of H. perforatum L. on metabolism is still unknown. In order to test whether H. perforatum L. extract (EHP) has an effect on metabolic syndrome, we treated diet induced obese (DIO) C57BL/6J mice with the extract. The chemical characters of EHP were investigated with thin-layer chromatography, ultraviolet, high-performance liquid chromatography (HPLC), and HPLC-mass spectrometry fingerprint analysis. Oral glucose tolerance test (OGTT), insulin tolerance test (ITT), and the glucose infusion rate (GIR) in hyperinsulinemic-euglycemic clamp test were performed to evaluate the glucose metabolism and insulin sensitivity. Skeletal muscle was examined for lipid metabolism. The results suggest that EHP can significantly improve the glucose and lipid metabolism in DIO mice. In vitro, EHP inhibited the catalytic activity of recombinant human protein tyrosine phosphatase 1B (PTP1B) and reduced the protein and mRNA levels of PTP1B in the skeletal muscle. Moreover, expressions of genes related to fatty acid uptake and oxidation were changed by EHP in the skeletal muscle. These results suggest that EHP may improve insulin resistance and lipid metabolism in DIO mice.

[A new lanostane-type triterpenoid from Cymbopogon citratus].

To study the chemical constituents of Cymbopogon citratus, isolation and purification of constituents were carried out on silica gel, Sephadex LH-20 and prepatative HPLC. The structures of the compounds were identified by physicchemical properties and spectral data analysis. Eight compounds were isolated and identified as 3beta-methoxy lanosta-9(11)-en-27-ol (1), 3beta-hydroxylanosta-9 (11)-en (2), (24S) -3beta-methoxylanosta-9(11), 25-dien-24-ol (3), 8-hydroxyl-neo-menthol (4), (2E)-3,7-dimethyl-2,7-octadiene-1, 6-diol (5), (+)-citronellol (6), 7-hydroxymenthol (7) and ethyl nonadecanoate(8). Compounds 1 is a new one. Compounds 2-3 are obtained from C. citratus for the first time.

Furostanol saponins from the seeds of Allium cepa L.

Allium cepa L. is one of the most widely cultivated and used plants. In addition to its bulb (onion), which is used as food in many cultures, the seeds of A. cepa L. are used as a traditional herbal medicine by the Uygur nationality in China to treat diarrhea and promote blood flow. In a bioactivity-screening, the ethanol extract of seeds of A. cepa L. showed inhibitory effects on protein tyrosine phosphatase 1B (PTP1B) enzyme, with 81.1% inhibition. Phytochemical investigation of the ethanol extract of red onion (Allium cepa L.) seeds led to the isolation of eight new furostanol saponins, named ceparosides E-L (1-8). Their structures were established using 1D and 2D NMR spectroscopy, mass spectrometry and chemical methods. Compounds 1-8 were screened for inhibitory effects on the PTP1B enzyme and cytotoxic activity against five human cells, including HCT-8, Bel-7402, BGC-823, A549 and A2780, but all were found to be inactive.

Hepatoprotective sesquiterpenes and rutinosides from Murraya koenigii (L.) Spreng.

Three new sesquiterpenes (1-3) and two new rutinosides (4 and 5) along with 17 known compounds (6-22) were isolated from the leaves of Murraya koenigii (L.) Spreng. The new compounds were elucidated as (3R,5S,6R)-3,5,6-trihydroxy-1,1,5-trimethylcyclohexyl-8-butyn-9-one (1), (8E,9R)-ethyl-7-(3S,5R,6S)-3,6-dihydroxy-1,1,5-trimethylcyclohexyl-9-hydroxybut-8-enoate (2), (3R)-3-O-ß-D-glucoside-6'-D-apiose-ß-ionone (3), 4-O-ß-D-rutinosyl-3-methoxyphenyl-1-propanone (4), and 1-O-ß-D-rutinosyl-2(R)-ethyl-1-pentanol (5) based on their spectroscopic data. Compounds 1, 4, 5, 18, and 21 (10 µM) exhibited moderate hepatoprotective activities.