Diverse prenylated C6-C3 derivatives from the stems and branches of Illicium ternstroemioides A. C. Smith with anti-inflammatory and antiviral activities.

Fifteen unreported prenylated C6-C3 derivatives (1-15) were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith, including one bis-prenylated C6-C3 derivative (1), three prenylated C6-C3 derivative-shikimic acid ester hybrids (2-4) and 11 prenylated C6-C3 monomers (5-15). The structures of compounds 1-15 were elucidated by spectroscopic analysis (UV, IR, 1D and 2D NMR, and HRESIMS). The absolute configurations of the compounds were determined using electronic circular dichroism (ECD), induced circular dichroism (ICD), and the modified Mosher's method. Among the isolates, compounds 11, 12, and 15 exhibited significant anti-inflammatory activities by inhibiting the nitric oxide with IC50 values ranging from 1.89 to 24.83 µM in lipopolysaccharide-stimulated murine RAW 264.7 macrophages and murine BV2 microglial cells; compounds 2, 3, and 7 exhibited antiviral activitives against Coxsackievirus B3 with an IC50 value of 33.3, 25.9, and 27.8 µM, respectively.

[Chemical constituents from leaves of Craibiodendron yunnanense].

The present study investigated the chemical constituents from the leaves of Craibiodendron yunnanense. The compounds were isolated and purified from the leaves of C. yunnanense by a combination of various chromatographic techniques including column chromatography over polyamide, silica gel, Sephadex LH-20, and reversed-phase HPLC. Their structures were identified by extensive spectroscopic analyses including MS and NMR data. As a result, 10 compounds, including melionoside F(1), meliosmaionol D(2), naringenin(3), quercetin-3-O-α-L-arabinopyranoside(4), epicatechin(5), quercetin-3'-glucoside(6), corbulain Ib(7), loliolide(8), asiatic acid(9), and ursolic acid(10), were isolated. Compounds 1 and 2 were two new compounds, and compound 7 was isolated from this genus for the first time. All compounds showed no significant cytotoxic activity by MTT assay.

New lignans and diterpenoid glycosides from the fruits of Xanthium italicum Moretti.

A pair of new lignans [(+)- 1 and (-)- 1] and three new compounds (2-4), together with a known compound 5, were isolated from the fruits of Xanthium italicum Moretti. The structures of these compounds were determined on the basis of spectroscopic analysis, particularly HR-ESI-MS and 1 D and 2 D NMR. Compounds 2 and 3 showed antinociceptive effects in an acetic acid-induced writhing test in mice with the writhe inhibition rates of 80.50% and 67.89% at the dose of 20 mg/kg, respectively.

[A new seco-prezizaane-type sesquiterpene lactone from stems and branches of Illicium ternstroemioides].

Three seco-prezizaane-type sesquiterpene lactones, one phenylpropanoid, and two lignans were isolated from the 95% ethanol extract of stems and branches of Illicium ternstroemioides with silica gel column chromatography, ODS column chromatography, and preparative HPLC. Based on the spectral data, they were identified as burmanicumolide D(1), veranisatin A(2), veranisatin B(3), dihydroconiferylalcohol(4), pinoresinol(5),(-)-matairesinol(6), respectively. Among them, compound 1 was a new seco-prezizaane-type sesquiterpene lactone, and 2-6 were obtained from this plant for the first time. None of these compounds display antiviral or cytotoxic activities.

Humulane-type and germacrane-type sesquiterpenoids from the fruits of Xanthium spinosum Linn.

Eight undescribed humulane-type sesquiterpenoids (xanthspinol A-E, I, J and N), three undescribed germacrane-type sesquiterpenoids (xanthspinol F, G and O) and twelve known compounds were isolated from the fruits of Xanthium spinosum. The structures of the undescribed compounds were elucidated by analyses of spectroscopic data, electronic circular dichroism (ECD) calculations, dimolybdenum tetraacetate [Mo2(OAc)4]-induced circular dichroism (ICD) spectra, a CD exciton chirality method and the modified Mosher's method. Xanthspinol A and B featured a humulane skeleton containing a 2,5-dihydrofuran fragment. Putative biosynthetic pathways for the undescribed compounds are proposed. Xanthspinol N, 8-epi-isoxanthanol and deacetyl-4-epixanthanol showed moderate activity against Coxsackie virus B3 (CVB3) with IC50 values of 8.70, 3.70 and 3.70 µM, respectively.

[Investigation on seco-prezizaane sesquiterpenes from fruits of Illicium lanceolatum and their neuroprotection activity].

Ten seco-prezizaane sesquiterpenes were isolated from the water-soluble fraction of the fruit of Illicium lanceolatum using the combined methods of silica gel column chromatography,Sephadex LH-20 column chromatography,and RP-preparative HPLC. They were elucidated as majusanol E( 1),2α-hydroxycycloparviflorolide( 2),2ß-hydroxy-3,6-dedioxypseudoanisatin( 3),majusanol A( 4),merrillianone( 5),cycloparvifloralone( 6),3α-hydroxycycloparvifloralone( 7),1,2-dehydrocycloparvifloralone( 8),henrylactone C( 9),and( 11) 7,14-ortholactone-3α-hydroxyfloridanolide( 10) according to the NMR data. All compounds were obtained from this plant for the first time. Neuroprotection activity,anti-Coxsackie B3 virus,and anti-H3 N2 virus experiments were carried out to test their bioactivities. The bioassay results showed that compounds 1,4,6,7,9 and 10 displayed weak protective effects of the damage of nerve SH-SY5 Y cell induced by monosodium glutamate.

Diverse epoxy grayanane diterpenoids with analgesic activity from the roots of Pieris formosa.

In our on-going study to investigate components with analgesic activity, eight new grayanane diterpenoids, epoxypieristoxins A-H (1-8), along with one known compound (9) were isolated from the roots of Pieris formosa. Their structures with absolute configurations were characterized by a series of spectroscopic methods and X-ray diffraction. Notably, compounds 1-5 represented the first example of natural grayanane diterpenoids possessed a 10,14-epoxy group. Whereas, compounds 6-7 were the first example of grayanane diterpenoid with a 7,10-epoxy group. Biological assays showed that compounds 1-3 and 5-8 displayed significant analgesic activity at a dose of 5.0 mg/kg (ip) compared to the vehicle tests (p < .05).

Minor Nortriterpenoids from the Twigs and Leaves of Rhododendron latoucheae.

A hyphenated NMR technique (analytical HPLC with a DAD connected to MS, SPE, and NMR) has proven effective for the full structural analysis and identification of minor natural products in complex mixtures. Application of this hyphenated technique to the CH2Cl2-soluble fraction of Rhododendron latoucheae led to the identification of 15 new minor ursane-type 28-nortriterpenoids (1-15). Compounds 1 and 12 inhibited HSV-1 with IC50 values of 6.4 and 0.4 µM, respectively.

3-Hydroxy-3-methylglutaryl flavone glycosides from the leaves of Turpinia arguta.

Three new 3-hydroxy-3-methylglutaryl (HMG) flavone 7-O-diglycosides, argutosides A-C (1-3); two new flavone 7-O-triglycosides, argutosides D-E (4-5); and one known apigenin 7-O-triglycoside (6), were isolated from the leaves of Turpinia arguta. The structures of these compounds were elucidated by spectroscopic and chemical techniques. The NO inhibitory activities of compounds 1-6 were evaluated using lipopolysaccharide-induced RAW264.7 cells. Only compound 2 showed a moderate inhibitory effect on NO production with an IC50 value of 25.74µM. Compounds 1-6 were not cytotoxic to RAW264.7 cells at 10µM.

Rhodoterpenoids A‒C, Three New Rearranged Triterpenoids from Rhododendron latoucheae by HPLC‒MS‒SPE‒NMR.

Rhodoterpenoids A‒C (1‒3), three new rearranged triterpenoids, together with one new biogenetically related compound, rhodoterpenoid D (4), were isolated and efficiently elucidated from Rhododendron latoucheae by high-performance liquid chromatography-mass spectrometry-solid-phase extraction-nuclear magnetic resonance (HPLC‒MS‒SPE‒NMR). Compounds 1 and 2 possess an unprecedented skeleton with a 5/7/6/6/6-fused pentacyclic ring system, while compound 3 contains a unique 6/7/6/6/6-fused pentacyclic carbon backbone. Their structures were determined by extensive spectroscopic methods and electronic circular dichroism (ECD) analyses. Plausible biogenetic pathways for 1‒4 were proposed. Compounds 1 and 4 showed potential activity against herpes simplex virus 1 (HSV-1) with IC50 values of 8.62 and 6.87 µM, respectively.

Pierisketolide A and Pierisketones B and C, Three Diterpenes with an Unusual Carbon Skeleton from the Roots of Pieris formosa.

Pierisketolide A (1) and pierisketones B and C (2 and 3), three diterpenes with an unusual A-homo-B-nor-ent-kaurane carbon skeleton, were isolated from the roots of Pieris formosa. Their structures were characterized by a series of spectroscopic methods, X-ray diffraction, and electronic circular dichroism (ECD). Pierisketolide A (1) exhibited an analgesic effect with a 45% writhe inhibition rate at a dose of 10.0 mg/kg. The plausible biosynthetic pathways of 1-3 are proposed.

Rhodomollins A and B, two Diterpenoids with an Unprecedented Backbone from the Fruits of Rhododendron molle.

Two new grayanoids, rhodomollin A (1) and rhodomollin B (2), possessing an unprecedented D-homo grayanane carbon skeleton, were isolated from the fruits of Rhododendron molle. The structures of 1 and 2 were fully characterized using a combination of spectroscopic analyses and X-ray crystallography. Rhodomollin B (2) exhibited modest activity against influenza virus A/95-359, with an IC50 value of 19.24 µM.

Antiviral Triterpenes from the Twigs and Leaves of Lyonia ovalifolia.

Eleven new 9,10-seco-cycloartan triterpene glycosides (1-11), seven new lanostane triterpene glycosides (12-18), and two new ursane triterpenoids (19-20) were isolated from the twigs and leaves of Lyonia ovalifolia. The structures of these compounds were elucidated by extensive MS and NMR spectroscopic analysis. The absolute configuration of compound 1a (the aglycone of 1) was established by X-ray crystallography, and that of C-24 in compounds 2, 7, and 12 was established by Mo2(OAc)4-induced electronic circular dichroism experiments. All compounds were evaluated for their antiviral [herpes simplex virus-1 (HSV-1), influenza A/95-359 (A/95-359), and Coxsackie B3 (CVB3)] activity. Compounds 1, 1a, 2a, 12a, 13, and 16 exhibited potent activity against HSV-1, with IC50 values from 2.1 to 14.3 µM, while compounds 1a, 2a, 12a, 13, and 12-2a exhibited potent activity against A/95-359, with IC50 values from 2.1 to 11.1 µM. In turn, compounds 1, 1a, 2a, 12a, and 13 exhibited potent activity against CVB3, with IC50 values from 2.1 to 11.1 µM.

Antinociceptive Grayanoids from the Roots of Rhododendron molle.

Nine new grayanoids (1-9), together with 11 known compounds, were isolated from the roots of Rhododendron molle. The structures of the new compounds (1-9) were determined on the basis of spectroscopic analysis, including HRESIMS, and 1D and 2D NMR data. Compounds 4, 6, 12, and 14-20 showed significant antinociceptive activities in an acetic acid-induced writhing test. In particular, 14 and 15 were found to be more potent than morphine for both acute and inflammatory pain models and 100-fold more potent than gabapentin in a diabetic neuropathic pain model.

A new thiophene and two new monoterpenoids from Xanthium sibiricum.

Three new compounds (1-3), together with six known compounds (4-9), were isolated from the fruits of Xanthium sibiricum. The structures and the absolute configurations of sibiricumthionol (1), (+)-(5Z)-6-methyl-2-ethenyl-5-hepten-1,2,7-triol [(+)-2], ( - )-(5Z)-6-methyl-2-ethenyl-5-hepten-1,2,7-triol [( - )-2], (2E,4E,1'S, 2'R, 4'S, 6'R)-dihydrophaseic acid (3), (+)-xanthienopyran [(+)-4] and ( - )-xanthienopyran [( - )-4] were established by extensive spectroscopic analyses, X-ray crystallographic analysis, ECCD analysis and ECD calculations. Caffeic acid (7) and caffeic acid ethyl ester (8) weekly inhibited α-glucosidase enzymatic activity by 44.5% and 40.2%, respectively, at 40 µM. Protocatechuic acid (9) selectively exhibited cytotoxicity against HepG2 cell lines, with an IC50 value of 2.92 µM.

Diketopiperazines and Sesquilignans from the Branches and Leaves of Claoxylon polot.

Six new diketopiperazines (1-6), two new sesquilignans (7-8), and ten known compounds (9-18) were isolated from the branches and leaves of Claoxylon polot. Their structures were elucidated by extensive spectroscopic analysis. The absolute configurations of 1-3 were assigned by computational methods. Compounds 1 and 2 exhibited antiviral activity against Coxsackie B3 virus with IC50 values of 14.6 and 25.9 µM, respectively.

Bioactive Sesquiterpenes and Lignans from the Fruits of Xanthium sibiricum.

Seven new sesquiterpenes (1, 3-8), a new sesquiterpene natural product (2), and two new lignans (9 and 10), together with 15 known compounds, were isolated from the fruits of Xanthium sibiricum. The structures of the new compounds were established by NMR spectroscopic analysis, ECD calculations, and Mo2(OAc)4-induced circular dichroism, with the structures of 1 and 4 confirmed by single-crystal X-ray diffraction. Compound 1 is the first example of a 3/5/6/5 tetracyclic eudesmane sesquiterpene lactone formed at C-6 and C-7. In turn, compound 4 is the first example of a natural xanthane tetranorsesquiterpene, while compounds 5-8 are the first xanthane trinorsesquiterpenes found to date. Compounds 8, 11-15, 17, and 24 exhibited indirect anti-inflammatory activity by suppressing the lipopolysaccharide-induced proinflammatory factors in BV2 microglial cells, with IC50 values between 1.6 and 8.5 µM. Furthermore, compounds 13 and 17 exhibited anti-inflammatory activity against ear edema in mice produced by croton oil, with inhibition rates of 46.9% and 37.7%, respectively. Compounds 8, 11, 12, 23, and 24 exhibited potent activity against influenza A virus (A/FM/1/47, H1N1) with IC50 values between 3.7 and 8.4 µM.

[Chemical constituents from roots of Illicium majus].

Ten compounds, including seven sesquiterpenes, two phenols and one phenylpropanoid, were isolated from the roots of Illicium majus by means of silica gel, ODS, Sephadex LH-20, and preparative HPLC. On analysis of MS and NMR spectroscopic data , their structures were established as cycloparviflorolide (1), cycloparvifloralone (2), tashironin (3), tashironin A (4), anislactone A(5), anislactone B (6), pseudomajucin (7), syringaldehyde (8), methyl-4-hydroxy-3, 5-dimethoxybenzoate (9), and (E)-3-methoxy-4,5-methylenedioxycinnamic alchol (10), respectively. Compounds 1-4 and 8-10 were first isolated from this plant. In the in vitro assays, at a concentration of 1.0 x 10(-5) mol x L(-1), compounds 5 and 6 were active against LPS induced NO production in microglia with a inhibition rate of 75.31% and 53.7%, respectively.

[Chemical constituents from stems of Brucea mollis and their cytotoxic activity].

Ten compounds were isolated from the stems of Brucea mollis by various chromatographic techniques such as column chromatography on silica gel and Sephadex LH-20, and preparative HPLC, and their structures were elucidated as deacetylated isobrucein B (1), indaquassin X (2), cleomiscosin A (3), cleomiscosin B (4), (+)-lyoniresinol (5), (+)-epipinoresinol(6), (+)-pinoresinol (7), (+)-syringaresinol (8), 4,5-dihydroblumenol A (9) and adenosine (10) on the basis of spectroscopic data analysiS. All compounds were obtained from this plant for the first time, moreover, compound 1 was a new natural product. Compound 2 showed significant cytotoxic activities against the human cell lines HT-29, HepG2, BGC-823 and SKOV3 with IC50 values of 0.84-3.97 micromol x L(-1).