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Mentha haplocalyx (Mentha canadensis) is widely used as a medicinal plant in traditional Chinese medicine, and the extracts of its aerial parts are found to significantly inhibit the activity of α-glucosidase with an IC50 value of 21.0 μg/mL. Bioactivity-guided isolation of the extracts afforded two new compounds (1 and 2), together with 23 known ones (3–25). Their structures were established by extensive spectroscopic analyses (1D and 2D NMR, MS, IR and UV). Compounds 1–17 and 21–25 were evaluated for their α-glucosidase inhibitory activities. Compound 11 was the most active ones with an IC50 values of 83.4 μM. These results verify the α-glucosidase inhibitory activity of M. haplocalyx (M. canadensis) and specify its active compounds for the first time. [ABSTRACT FROM AUTHOR]

Pinuskesiols A–F (1 – 6), six new structurally diverse abietane diterpenoids were isolated from Pinus yunnanensis resins. Their structures including absolute configurations were characterized by using spectroscopic and computational methods. All the compounds bear a carbonyl functionality at C-4 with 1 and 2 behaving as a lactone thereof. The isopropyl group is attached to C-13 via O -atom in 3. In addition, the presence of a Δ 5(6) double bond and a ketone at C-7 makes 2 a large conjugated system. Biological evaluation revealed that 1 , 2 , and 4 could concentration-dependently inhibit iNOS and COX-2 expression in lipopolysaccharide-induced RAW 264.7 cells with 2 to be the most active toward COX-2 inhibition. Pinuskesiols A–F (1 – 6), six new structurally diverse abietane diterpenoids were isolated from Pinus yunnanensis resins. Their structures including absolute configurations were characterized by using spectroscopic and computational methods. All the compounds bear a carbonyl functionality at C-4 with 1 and 2 behaving as a lactone thereof. The isopropyl group is attached to C-13 via O -atom in 3. In addition, the presence of a Δ 5(6) double bond and a ketone at C-7 makes 2 a large conjugated system. Biological evaluation revealed that 1 , 2 , and 4 could concentration-dependently inhibit iNOS and COX-2 expression in lipopolysaccharide-induced RAW 264.7 cells with 2 to be the most active toward COX-2 inhibition. [Display omitted] [ABSTRACT FROM AUTHOR]

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-β-d-xylopyranoside (1), orcinol-1-O-β-d-apiofuranosyl-(1 → 2)-β-d-glucopyranoside (2), orcinol-3-O-β-d-apiofuranosyl-1-O-β-d-glucopyranoside (3), and 1-O-β-d-glucopyranosyl-4-ethoxyl-3-hydroxymethylphenol (4). [ABSTRACT FROM AUTHOR]

One unusual stilbene trimer-flavonoid hybrid, paeonilactiflobenoid (1), together with six known stilbenes (2–7) were isolated from the seeds of Paeonia lactiflora. The structure of 1 was elucidated with the aid of HRESIMS, 1D and 2D NMR, [ α ] D spectroscopic data and ECD calculation. Compounds 2 – 7 showed stimulative effects on GLP-1 secretion with promoting rates of 79.8%–880.4% (25 μM) and 217.6%–1089.4% (50 μM), more potent than the positive control, oleoylethanolamide (250.2% at 50 μ M). Moreover, compounds 4 and 6 exhibited agonistic activity on the G protein-coupled receptor (GPCR) TGR5 with stimulative ratios of 40.2% and 40.5% at 50 μM, and 54.2% and 49.1% at 100 μM, respectively. Docking study manifested that 6 well located in the catalytic pocket of TGR5 by hydrogen-bond and hydrophobic interactions. The GLP-1 promotion of 6 could be attenuated by IP 3 , Ca2+/CaMKII and MEK/ERK pathway inhibitors, suggesting that these pathways played important roles in GLP-1 secretion. Thus, stilbenes in peony seeds maybe regarded as potential GLP-1 secretagogues through TGR5-IP 3 -Ca2+/CaMKII-MEK/ERK pathways. [Display omitted] • One usual stilbene trimer-flavonoid hybrid was isolated from peony seeds. • Six stilbenes showed stimulative effects on GLP-1 secretion. • Compounds 4 and 6 exhibited agonistic activity on TGR5 receptor. • The GLP-1 promotion of 6 was attenuated by IP 3 , Ca2+/CaMKII and MEK/ERK inhibitors. [ABSTRACT FROM AUTHOR]

Artemdubosides A-E (1–5), the first examples of natural polyacetylenes substituted by 6'- O -crotonyl β- glucopyranoside, and artemdubosides F-G (6–7) that were two unusual polyacetylenes featuring a 6'- O -acetyl β- glucopyranoside moiety, were isolated from Artemisia dubia var. subdigitata. Their structures were elucidated based on the spectral data including HRESIMS, UV, IR, 1D and 2D NMR, and ECD calculations. Antihepatoma assay suggested that compound 1 exhibited activity against HepG2, Huh7, and SK-Hep-1 cells with inhibitory ratios of 77.1%, 90.8%, and 73.1% at 200.0 μM, respectively. [Display omitted] • Artemdubosides A-G (1 – 7) were isolated from Artemisia dubia var. subdigitata. • Compounds 1 – 5 represented the first examples of natural polyacetylenes substituted by 6′-O-crotonyl β-glucopyranoside. • Compounds 6 – 7 represented the first examples of natural polyacetylenes substituted by 6′- O -acetyl β-glucopyranoside. • Compound 1 showed activity against HepG2, Huh7, and SK-Hep-1 cells at 200.0 μM. [ABSTRACT FROM AUTHOR]

Abstract Ethnopharmacological relevance Traditional Chinese medicines (TCMs) are fascinating sources for natural drug candidates. Uncaria rhynchophylla (Gouteng) is a famous TCM used for alleviating central nervous system (CNS) disorders, while its antidepressant constituents are still disputed. Aim of the study The present study was designed to assess the antidepressant property of U. rhynchophylla and characterize the active constituents targeting melatonin receptors which are closely related to CNS diseases. Materials and methods The total extract and each fraction of U. rhynchophylla were extensively assessed for their agonistic activity on melatonin receptors in vitro. The following bioassay-guided fractionation yielded the active constituents, whose activity was confirmed by dose-dependent bioassay and antagonistic experiment on HEK293 cells. Their antidepressant effects were evaluated on forced swimming test (FST), tail suspension test (TST) and open-field test (OFT) mice models in vivo. Their metabolic profiles in mice plasma were analyzed by LCMS-IT-TOF. Results The stems and hooks of U. rhynchophylla were revealed with agonistic activity on melatonin receptors (MT 1 and MT 2). Under the guidance of bioassay, two flavanols, catechin and epicatechin were obtained and showed obviously activity agitating MT 1 (EC 50 = 25.8 and 156.1 μM) and MT 2 (EC 50 = 47.3 and 208.8 μM) receptors. The agonistic activity of catechin on melatonin receptors can be antagonized by luzindole at the concentrations of 1.57–100 μM. Catechin could significantly reduce the immobility time in both FST and TST mice models at doses of 80 and 40 mg/kg, without obvious effect on locomotor activity in OFT mice model. Five phase II (M1-M5) and one phase I (M6) metabolites of catechin were detected in mice plasma after intragastric (i.g.) administration. Conclusion Catechin is a potent antidepressant candidate from U. rhynchophylla by targeting melatonin receptors. The main metabolic pathways of catechin in mice plasma are glucuronidation (M3) and methylated glucuronidation (M4 and M5). This study provides valuable information for understanding the antidepressant potency of Gouteng and its active constituents. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Abstract Our random bioassay revealed that the CHCl 3 part of Chelonopsis praecox (Lamiaceae) showed significant activity against α -glucosidase with the inhibitory rate of 99.6 ± 0.4 % (330 μg/mL). Bioassay-guided isolation yielded seven new ent -kaurane diterpenoids, chepraecoxins A-G (1 - 7), and three known ones (8 - 10), driven by LC-MS analyses. The structures of chepraecoxins A-G (1 - 7) were elucidated by X-ray crystallographic and extensive spectroscopic analyses. Compounds 1 , 6 , and 10 showed obvious α -glucosidase inhibitory effects with IC 50 values of 305.0, 361.0 and 174.5 μM, respectively. Enzyme kinetics study suggested that compound 1 inhibited the α -glucosidase by a noncompetitive type mechanism (K i = 354.4 μM). Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Paeoveitols A–E ( 1 – 5 ), involving three monoterpenes and two benzofuran constituents, were isolated from Paeonia veitchii . Their structures were determined based on extensive spectral analyses (IR, UV, MS, 1D and 2D NMR), and the absolute configuration of compound 1 was confirmed by single-crystal X-ray diffraction. By the agitating human melatonin receptor 1 (MT1) assay on HEK293 cell line in vitro, compound 4 showed weak activity with the agitation rate of 22.52% at the concentration of 1.79 mM. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance The rhizome of Cyperus rotundus ( C. rotundus ) is a well-known traditional Chinese medicine to cure hepatitis in many formulae, but the active components responsible for hepatitis have not been elucidated. According to our bioassay on HepG2.2.15 cell line in vitro , the ethanol extract of C. rotundus demonstrated potent anti-HBV activity. This current study was designed to isolate and identify the anti-HBV active constituents from the rhizomes of C. rotundus . Material and methods Bioactivity and LC-MS guided fractionation on the extract of C. rotundus using various chromatographic techniques including open-column, Sephadex LH-20 and semi-preparative high performance liquid chromatography led to the isolation and identification of thirty-seven sesquiterpenoids. Structural elucidation of the isolates was carried out by extensive spectroscopic analyses (UV, IR, HRMS, 1D- and 2D –NMR). The anti-HBV activity and cytotoxicity were evaluated on the HBV-transfected HepG2.2.15 cell line in vitro . The cytotoxicity effects of the isolates were assessed by a MTT assay. The secretions of HBsAg and HBeAg in the culture medium were detected by ELISA method, and the load of HBV DNA was quantified by real-time fluorescent PCR technique. Results Five new patchoulane-type sesquiterpenoids, namely cyperene-3, 8-dione ( 1 ), 14-hydroxy cyperotundone ( 2 ), 14-acetoxy cyperotundone ( 3 ), 3 β -hydroxycyperenoic acid ( 4 ) and sugetriol-3, 9-diacetate ( 5 ), along with 32 known sesquiterpenoids were isolated from the active fractions of C. rotundus . Compounds 2 and 3 were the first cyperotundone-type sesquiterpenoids with a hydroxyl group at C-14 position. Nine eudesmane-type sesquiterpenoids ( 15 – 21 and 23 – 24 ) significantly inhibited the HBV DNA replication with IC 50 values of 42.7±5.9, 22.5±1.9, 13.2±1.2, 10.1±0.7, 14.1±1.1, 15.3±2.7, 13.8±0.9, 19.7±2.1 and 11.9±0.6 μM, respectively, of which, compounds 17 , 21 , 23 and 24 possessed high SI values of 250.4, 125.5,>259.6 and 127.5, respectively. Two patchoulane-type sesquiterpenoids ( 4 and 7 ) effectively suppressed the secretion of HBsAg in a dose-dependent manner with IC 50 values of 46.6±14.3 (SI=31.0) and 77.2±13.0 (SI=1.7) μM, respectively. Compounds 2 , 8 , 12 , 15 , 17 and 25 possessed moderate activities against HBeAg secretion with IC 50 values of 162.5±18.9 (SI=13.3), 399.2±90.0 (SI=10.6), 274.7±70.8 (SI=5.2), 313.9±87.5 (SI=7.2), 334.0±70.4 (SI=9.9) and 285.3±20.9 (SI=15.5) μM, respectively. Conclusions This is the first study to reveal the anti-HBV constituents of C. rotundus , demonstrating that the eudesmane-type sesquiterpenoids might contribute to the anti-HBV activity of the rhizomes of C. rotundus . [ABSTRACT FROM AUTHOR]

Three new secoiridoid aglycones of (−)-swermusic acid A ( 1 ) and B ( 3 ), and (−)-swerimuslatone A ( 2 ), and four new secoiridoid glycosides of 6′- O -formylsweroside ( 4 ), 6′- O -formylgentiopicroside ( 5 ), 6′- O -acetylamarogentin ( 6 ) and 6′- O -acetylamaronitidin ( 7 ), along with 40 known compounds ( 8 – 47 ) were isolated from Swertia mussotii . Their structures were elucidated on the basis of extensive spectroscopic analyses including MS, IR, UV, 1D- and 2D-NMR. Forty-five compounds from S. mussotii were evaluated for their anti-HBV activity on the HepG 2.2.15 cell line in vitro inhibiting the secretions of HBsAg and HBeAg, as well as HBV DNA replication. Six of the nine phenols 26 – 29 , 31 and 32 exhibited activities inhibiting HBsAg and HBeAg secretion with IC 50 values from 0.23 to 5.18 mM, and HBV DNA replication with IC 50 values from < 0.06 to 2.62 mM. Moreover, isooriention ( 45 ) displayed significant anti-HBV activities against secretions of HBsAg and HBeAg with IC 50 value of 0.79 and 1.12 mM, as well as HBV DNA replication with IC 50 value of 0.02 mM. [ABSTRACT FROM AUTHOR]

Five new secoiridoid glycosides, swericinctosides A and B ( 1 – 2 ), 9- epi swertiamarin ( 3 ), 2′- O - m -hydroxybenzoyl swertiamarin ( 4 ), 4″- O -acetyl swertianoside E ( 5 ), and one unusual lactonic enol ketone, 3-(hydroxymethyl ene) dihydro- 2H -pyran-2, 4( 3H )-dione ( 6 ), together with three known compounds, swertiaside ( 7 ), swertianoside C ( 8 ) and decentapicrin B ( 9 ) were isolated from Swertia cincta . The structures of the new compounds were determined by extensive spectroscopic analyses including 1D and 2D NMR, HRESIMS, UV, IR and [α] D spectra. Anti-HBV assay on HepG 2.2.15 cell line in vitro demonstrated that compounds 1 – 9 possessed inhibitory activity on HBV DNA replication with IC 50 values from 0.05 to 1.83 mM, and compounds 1 , 3 , 5 , 7 and 8 could inhibit the secretion of HBsAg with IC 50 values from 0.24 to 1.06 mM. [ABSTRACT FROM AUTHOR]

Four new compounds swertiachiralatone A (1), swertiachoside A (2), swertiachirdiol A (3) and swertiachoside B (4), together with twenty-six known ones were isolated from the ethanol extract of Swertia chirayita . Their structures were elucidated by extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, IR and [ α ] D ). All compounds were evaluated for anti-hepatitis B virus (anti-HBV) activities on HepG 2.2.15 cells line in vitro , of which compounds 14 and 19 showed inhibitory activity on hepatitis B surface antigen (HBsAg) secretion with IC 50 values of 0.31 ± 0.045 and 1.49 ± 0.033 mM; compounds 14 and 28 exhibited activity against hepatitis B e antigen (HBeAg) secretion with IC 50 values of 0.77 ± 0.076 and 5.92 ± 1.02 mM; and eight compounds (8,9,13,14,24–26,29) possessed activity against HBV DNA replication with IC 50 values of 0.07–0.33 mM. In particular (+)-cycloolivil-4′- O - β - d -glucopyranoside (14) exhibited inhibition not only on the secretions of HBsAg and HBeAg with IC 50 values of 0.31 ± 0.045 mM (SI = 4.29) and 0.77 ± 0.076 mM (SI = 1.75), respectively, but also on HBV DNA replication with an IC 50 value of 0.29 ± 0.034 mM (SI = 4.66). [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Hepatitis B induced by HBV is a serious health problem. Artemisia capillaris (Yin-Chen) has long been used to treat hepatitis in traditional Chinese medicine. Coumarins, flavonoids and organic acids were revealed as its hepatoprotective and choleretic components, but its anti-HBV active components remain unknown. This current study focused on its anti-HBV active constituents by various chromatographic methods. Material and methods LC/MS and bioassay-guided fractionation on the active extract of Artemisia capillaris led to the isolation of nine chlorogenic acid analogues. Structures of the isolates were elucidated by MS/MS and NMR techniques. Anti-HBV assay was performed on HepG 2.2.15 cell line in vitro : reduction of HBsAg and HBeAg secretions was measured by an ELISA method; inhibition of HBV DNA replication was monitored by real-time quantitative PCR and cellular toxicity was assessed by a MTT method. Results The 90% ethanol extract of Artemisia capillaris (Fr. AC) showed significantly inhibitory activity on HBV DNA replication with an IC 50 value of 76.1±3.9 μg/mL and low cytotoxic effects (SI>20.1). To clarify its active constituents, the extract was further separated into 3 sub-fractions (AC-1, AC-2 and AC-3), of which Fr. AC-2 was the most active fraction against HBeAg secretion and HBV DNA replication with IC 50 values of 44.2±2.8 and 23.2±1.9 μg/mL. Nine chlorogenic acid analogues were detected from the active part (Fr. AC-2) by a LC/MS technique and further separated by a HPLC method. The isolates were determined as chlorogenic acid ( 1 ), cryptochlorogenic acid ( 2 ), neochlorogenic acid ( 3 ), 3,5-dicaffeoylquinic acid ( 4 ), 4,5-dicaffeoylquinic acid ( 5 ), 3,4-dicaffeoylquinic acid ( 6 ), chlorogenic acid methyl ester ( 7 ), cryptochlorogenic acid methyl ester ( 8 ), neochlorogenic acid methyl ester ( 9 ). Compounds 1 – 6 possessed potent activity against HBV DNA replication with IC 50 values in the range of 5.5±0.9–13.7±1.3 μM. Di-caffeoyl analogues ( 4 – 6 ) also exhibited activity against the secretions of HBsAg and HBeAg. Esterified analogues ( 7 – 9 ) showed dramatically decreased anti-HBV activity, indicating that carboxyl group is closely associated to the anti-HBV activity. Conclusions This investigation was focused on the active fractions of Artemisia capillaris and their active compositions, which showed that Fr. AC-2 was the main active section of Artemisia capillaris and chlorogenic acid analogues were the main constituents contributing to its anti-HBV activity. These results support the ethnopharmacological use of Artemisia capillaris as anti-HBV agents. [ABSTRACT FROM AUTHOR]

Abstract: Six new 14-noreudesmane sesquiterpenoids, nicotabacosides A–F (1–6), along with five known sesquiterpenoids (7–11), were isolated from the leaves of Nicotiana tabacum. The structures of compounds 1–6 were elucidated as isorishitin 3-O-β-d-glucopyranoside (1), rishitin 3-O-β-d-glucopyranoside (2), rishitin 2-O-β- d-glucopyranoside (3), 1, 6-dehydro-rishitin 3-O-β-d-glucopyranoside (4), 2-hydroxyl-ligudentatol 3-O-β-d-glucopyranoside (5) and oxyglutinosone 3-O-β-d-glucopyranoside (6) based on extensive spectroscopic analyses (HRESIMS, UV, IR, 1D and 2D NMR). Their absolute configurations were determined by X-ray single-crystal diffraction and comparison of their electronic circular dichroism (ECD) spectra. [Copyright &y& Elsevier]

Abstract: Three new polyacetylenes, 8-(Z)-decene-4, 6-diyne-1, 3, 10-triol (1), 1, 3S, 8S-trihydroxydec-9-en-4, 6-yne (2), 3S, 8S-dihydroxydec-9-en-4, 6-yne 1-O-β -D-glucopyranoside (3), and one new glucosyl caffeoate, 1-O-ethyl-6-O-caffeoyl-β -D-glucopyranose (4), together with 34 known compounds were isolated from Artemisia capillaris. The structures of the new compounds were determined by extensive spectroscopic analyses including 1D and 2D NMR, HRESIMS, [α]D and CD experiments. Among them, 19 compounds showed activity inhibiting HBsAg secretion; 20 compounds showed activity inhibiting HBeAg secretion; and 25 compounds possessed inhibitory activity against HBV DNA replication according to our anti-HBV assay on HepG 2.2.15 cell line in vitro. The most active compound 12 could inhibit not only the secretions of HBsAg and HBeAg, but also HBV DNA replication with IC50 values of 15.02μM (SI=111.3), 9.00μM (SI=185.9) and 12.01μM (SI=139.2). [Copyright &y& Elsevier]

Abstract: Four new C18-diterpenoid alkaloids, weisaconitines A–D (1–4), were isolated from Aconitum weixiense. Based on extensive UV, IR, MS, 1D and 2D NMR analyses, their structures were elucidated as 8-O-ethyldolaconine (1), 4-demethylgenicunine B (2), 14-oxoaconosine (3), and 8-O-ethylaconosine (4). The analgesic activity of compound 4 was studied with CH3COOH-induced writhing model in mice. Compound 4 showed writhing inhibitions of 24% (50mg/kg), 26% (100mg/kg) and 34% (200mg/kg), respectively, as compared to the reference drug aspirin (63%) at a dose of 200mg/kg. [Copyright &y& Elsevier]

Abstract: Three new secoiridoids, swermacrolactones A–C (1–3), together with fourteen known compounds were isolated from Swertia macrosperma. Their structures were elucidated based on extensive spectroscopic analyses (IR, UV, MS, 1D and 2D NMR). By anti-HBV assay on the Hep G 2.2.15 cell line in vitro, the most active compound, luteolin (9), inhibited the secretion of hepatitis B virus surface antigen (HBsAg) and hepatitis B virus e antigen (HBeAg) with IC50 values of 0.02 and 0.02mM, respectively. [Copyright &y& Elsevier]

Abstract: Four new triterpenoids, sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4), along with nineteen known compounds (5–23) were isolated from Swertia yunnanensis. Based on extensive spectroscopic analyses (1D- and 2D-NMR, HRESIMS, UV, IR, [α]D), the structures of sweriyunnangenin A (1), sweriyunnanosides A (2), B (3) and C (4) were elucidated as taraxer-14-ene-3α,6β-diol, oleanolic acid 28-O-β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranoside, 2α,3β-di-hydroxyolean-12-en-28-oic acid 28-O-β-d-glucopyranosyl(1→6)-β-d-glucopyranosyl (1→6)-β-d-glucopyranosyl(1→2)-β-d-glucopyranoside and hederagenin 28-O-β-d-glucopyranosyl(1→6)-β-d-glucopyranosyl(1→6)-β-d-glucopyranosyl(1→2)-β-d-glucopyranoside, respectively. Twenty-two compounds were evaluated for their anti-HBV activities on the HepG 2.2.15 cell line in vitro, of which nine compounds showed potent anti-HBV activities. Compounds 1, 5–6, 14–16 and 19 showed activities against the secretion of HBsAg (IC50 values from 0.10 to 1.76mM) and HBeAg (IC50 values from 0.04 to 1.41mM), and compounds 11 and 13–16 exhibited significant inhibition on HBV DNA replication (IC50 values from 0.01 to 0.09mM). [Copyright &y& Elsevier]

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 IC50 value of 2.08mM on hepatitis B virus (HBV) e antigen (HBeAg) secretion of the HepG2.2.15 cell line. [Copyright &y& Elsevier]

Abstract: Aim of the study: Previously, we reported that the petroleum ether fraction, RC-1, and EtOAc fraction, RC-2, of the medicinal plant Rhus chinensis showed potent anti-HIV-1 activities. To address anti-HIV-1 constituents of RC-1 and RC-2, 17 compounds were isolated. Anti-HIV-1 activities and possible action mechanisms of these compounds were investigated. Methods: The syncytial formation induced by HIV-1 was determined under the inverted microscope, cellular toxicity and protection assay were assessed by MTT method, reduction of p24 antigen expression level and RT activity were measured by ELISA, and inhibition of recombinant HIV-1 PR was monitored by the fluorescent signal. Results: The compounds 1 and 13 inhibited HIV-1-induced syncytium formation potently with TI value of 42.31 and 19.07, respectively. Compounds 4, 5, 6, 9 and 10 were less potent with TI value of 8.94, 8.22, 4.14, 5.11 and 5.34, respectively. Compound 1, a benzofuranone-type compound, previously reported as a novel anti-HIV-1 agent, might target late-steps of HIV-1 life cycle. Compound 13 inhibited HIV-1 replication with EC50 of 7.16μg/ml and might target at/before integration step. Conclusion: These compounds might contribute to anti-HIV-1 activities extracts of the medicinal plant Rhus chinensis. [Copyright &y& Elsevier]

Abstract: Rhus chinensis, a species used in folk medicine by Chinese native people, the anti-HIV-1 activities of the petroleum ether, ethyl acetate, butanol and aqueous extract of Rhus chinensis, named as RC-1, RC-2, RC-3 and RC-4, respectively, was evaluated. The petroleum ether extract RC-1 can inhibit the syncytium formation and HIV-1 p24 antigen at non-cytotoxic concentrations, the 50% effective concentration (EC50) were 0.71 and 0.93μg/ml, respectively. The therapeutic index (TI) was about 100. RC-1 had no activity on inhibiting HIV-1 recombinant RT and HIV-1 entry into host cells. Results showed that RC-1 was effective against HIV-1 and Rhus chinensis would be a useful medicinal plant for the chemotherapy of HIV-1 infection. RC-1 might inhibit the post steps or target the new sites of HIV-1 replication. [Copyright &y& Elsevier]