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1.
Bioassay guided fractionation of the roots of Lantana montevidensis (Verbenaceae) has resulted in the isolation and identification of three new triterpenoids; 13β-hydroxy-3-oxo-olean-11-en-28-oic acid (1), 12β,13β-dihydroxyolean-3-oxo-28-oic acid (2) and 12β,13β,22β-trihydroxyolean-3-oxo-28-oic acid (3) in addition to nine known compounds: oleanonic acid (4), oleanolic acid (5), 3β,25β-dihydroxy-olean-12-en-28-oic acid (6), lantadene A (7), 19α-hydroxy-3-oxo-olean-12-en-28-oic acid (8) pomolic acid (9), camaric acid (10) together with β-sitosterol (11) and β-sitosterol-3-O-β-d-glucoside (12). The structures of the isolated metabolites were elucidated based on comprehensive 1D and 2D NMR spectroscopic data as well as HR-ESI–MS. The extracts and the isolated metabolites were evaluated for their antiprotozoal and antimicrobial activities. Compound 2 showed antibacterial activity against Staphylococcus aureus and methicillin resistant S. aureus with IC50 values against both organisms of 2.1 μM and compound 10 showed activity against same organisms with IC50 values 8.74 and 8.09 μM, respectively, compared to the positive control ciprofloxacin (IC50 = 0.3 μM against S. aureus and MRSA). Compounds 1, 4, 5, 6, and 10 showed moderate antileishmanial activity with IC50 values ranging between (2.54–14.95 μM) and IC90 values ranging between (11.90–19.47 μM), using pentamidine as a control (IC50 values 2.09  16.8 μM) and IC90 values ranging between (4.72  16.8 μM). These compounds also showed highly potent antitrypanosomal activity with IC50 values ranging between (0.39–7.12 μM) and IC90 values ranging between (1.91–10.51 μM), which are more efficient than the DFMO, the antitrypanosomal drug employed as positive control (IC50 and IC90values 11.82 and 30.82 μM).  相似文献   

2.
Two new butyrolactones: aspernolides F (6) and G (7), together with three stigmasterol derivatives: (22E,24R)-stigmasta-5,7,22-trien-3-β-ol (1), stigmast-4-ene-3-one (2), and stigmasta-4,6,8(14), 22-tetraen-3-one (3), two meroterpenoids: terretonin A (4) and terretonin (5), and a butyrolactone derivative: butyrolactone VI (8) have been isolated from the endophytic fungus Aspergillus terreus isolated from the roots of Carthamus lanatus (Asteraceae). Their structures were determined by spectroscopic means (1D, 2D NMR, and HRESIMS), as well as optical rotation measurement and comparison with literature data. The isolated compounds were evaluated for their anti-microbial, anti-malarial, anti-leishmanial, and cytotoxic activities. Compound 1 displayed a potent activity against MRSA and C. neoformans with IC50 values of 0.96 μg/mL and 4.38 μg/mL, respectively compared to ciprofloxacin (IC50 0.07 μg/mL) and amphotericin B (IC50 0.34 μg/mL), respectively. While, 6 showed good activity against C. neoformans (IC50 5.19 μg/mL) and mild activity against MRSA (IC50 6.39 μg/mL). Moreover, 1 and 2 exhibited very good anti-leishmanial activity towards L. donovani with IC50 values of 4.61 and 6.31 μg/mL, respectively and IC90 values of 6.02 and 16.71 μg/mL, respectively.  相似文献   

3.
Overcoming drug resistance with remarkable cytotoxic activity by anthracene-9,10-dione derivatives would offer a potential therapeutic strategy. In this study, we report the synthesis and the cytotoxicity of a novel set of anthraquninones. (4-(4-Aminobenzylamino)-9,10-dioxo-9,10-dihydroanthracen-1-yl-4-methylbenzenesulfonate) (3) has excellent in vitro cytotoxicity against doxorubicin-resistant cancer cell line (IC50 = 0.8 μM), 20-fold higher than doxorubicin. The cytotoxic effect via G2/M arrest does not appear to be ROS.  相似文献   

4.
Three novel compounds; two polymethoxylated flavonoids, 5,7,4′-trihydroxy-3,8,3′,5′-tetramethoxyflavone (1), 5,7,3′-trihydroxy-3,8,4′,5′-trimethoxyflavone (2), and a clerodane diterpenoid; 8-acetoxyisochiliolide lactone (3) were characterized from the leaf exudates of Microglossa pyrifolia. In addition, three known polymethoxylated flavonoids including; 5,7,4′-trihydroxy-3,8,3′-trimethoxyflavone (4), 5,3′4′-trihydroxy-3,7,8-trimethoxyflavone (5), 5,3′4′-trihydroxy-7-methoxyflavanone (6) and a clerodane diterpenoid; 7,8-epoxyisocholiolide lactone (7) were identified. Their structures were determined on the basis of spectroscopic evidence. All the compounds did not exhibit antiplasmodial and antimicrobial activities at 47.6 μg/mL and were not cytotoxic at 5 μg/mL. Compound 6 exhibited modest antileishmanial activity with IC50 value of 13.13 μg/mL with 5 and 7 showing activities with IC50 values of 31.13 and 38.00 μg/mL, respectively, therefore inactive. The flavonoids (quercetin derivatives, 4 and 5) showed similar antioxidant activities, using 2,2-diphenylpicrylhydrazyl (DPPH) assay, with IC50 values of 6.2 ± 0.3 μg/mL for 4 (17.3 μM) and 5 (17.8 μM) respectively. These activities were comparable to that of the standard quercetin (IC50 value of 6.0 ± 0.2 μg/mL (19.9 μM)), irrespective of methylation of the characteristic hydroxyl groups expected to be responsible for activity and additional substitution at C-8 in ring A of the flavonoid ring. These studies revealed that the presence of an hydroxyl group at C-4′ positions and oxygenation at C-3 in flavone skeleton, appears to be necessary for good antioxidant activities as encountered in compounds 1, 4 and 5. Substantial reduction in antioxidant activity was shown by methoxylation of the 4′-OH as observed in compound 2 with an IC50 value of 8.79 ± 0.3 μg/mL (24.4 μM).  相似文献   

5.
Bioassay-guided isolation and purification of the ethyl acetate extract of Moringa oleifera fruits yielded three new phenolic glycosides; 4-[(2′-O-acetyl-α-l-rhamnosyloxy) benzyl]isothiocyanate (1), 4-[(3′-O-acetyl-α-l-rhamnosyloxy)benzyl]isothiocyanate (2), and S-methyl-N-{4-[(α-l-rhamnosyloxy)benzyl]}thiocarbamate (3), together with five known phenolic glycosides (48). The structures of the new metabolites were determined on the basis of spectroscopic analyses including 1D- and 2D-NMR and mass spectrometry. The anti-inflammatory activity of isolated compounds was investigated with the lipopolysaccharide (LPS)-induced murine macrophage RAW 264.7 cell line. It was found that 4-[(2′-O-acetyl-α-l-rhamnosyloxy)benzyl]isothiocyanate (1) possessed potent NO–inhibitory activity with an IC50 value of 1.67 μM, followed by 2 (IC50 = 2.66 μM), 4 (IC50 = 2.71 μM), and 5 (IC50 = 14.4 μM), respectively. Western blots demonstrated these compounds reduced LPS-mediated iNOS expression. In the concentration range of the IC50 values, no significant cytotoxicity was noted. Structure–activity relationships following NO-release indicated: (1) the isothiocyanate group was essential for activity, (2) acetylation of the isothiocyanate derivatives at C-2′ or at C-3′ of rhamnose led to higher activity, (3) un-acetylated isothiocyanate derivatives displayed eight times less activity than the acetylated derivatives, and (4) acetylation of the thiocarbamate derivatives enhanced activity. These data indicate compounds 1, 2, 4 and 5 are responsible for the reported NO-inhibitory effect of Moringa oleifera fruits, and further studies are warranted.  相似文献   

6.
Two new lignans, gymnothelignans V (1) and W (2), were isolated from a methanol extraction of Gymnotheca chinensis Decne. Their structures were established on the basis of extensive 1D and 2D NMR spectroscopy. Compound 1 exhibited moderate cytotoxicity against the HCT116, HCT15, A549, MCF-7 and HepG2 cancer cell lines with IC50 values of 45.1 μM, 26.9 μM, 49.6 μM, 30.0 μM and 49.7 μM, respectively. Compound 2 exhibited weak cytotoxicity against the A549 cancer cell line with an IC50 value of 41.3 μM.  相似文献   

7.
The efficient synthesis of a new series of polyhydroxylated dibenzyl ω-(1H-1,2,3-triazol-1-yl)alkylphosphonates as acyclic nucleotide analogues is described starting from dibenzyl ω-azido(polyhydroxy)alkylphosphonates and selected alkynes under microwave irradiation. Selected O,O-dibenzylphosphonate acyclonucleotides were transformed into the respective phosphonic acids. All compounds were evaluated in vitro for activity against a broad variety of DNA and RNA viruses and for cytostatic activity against murine leukemia L1210, human T-lymphocyte CEM and human cervix carcinoma HeLa cells. Compound (1S,2S)-16b exhibited antiviral activity against Influenza A H3N2 subtype (EC50 = 20 μM—visual CPE score; EC50 = 18 μM—MTS method; MCC >100 μM, CC50 >100 μM) in Madin Darby canine kidney cell cultures (MDCK), and (1S,2S)-16k was active against vesicular stomatitis virus and respiratory syncytial virus in HeLa cells (EC50 = 9 and 12 μM, respectively). Moreover, compound (1R,2S)-16l showed activity against both herpes simplex viruses (HSV-1, HSV-2) in HEL cell cultures (EC50 = 2.9 and 4 μM, respectively) and feline herpes virus in CRFK cells (EC50 = 4 μM) but at the same time it exhibited cytotoxicity toward uninfected cell (MCC  4 μM). Several other compounds have been found to inhibit proliferation of L1210, CEM as well as HeLa cells with IC50 in the 4–50 μM range. Among them compounds (1S,2S)- and (1R,2S)-16l were the most active (IC50 in the 4–7 μM range).  相似文献   

8.
The series of imidazoldine-2-thiones 2 and tetrahydropyrimidine-2-thiones 3 were discovered as inhibitor of α-MSH-induced melanin production in melanoma B16 cells. The primary bioassay showed that 1-(4-ethylbenzyl)-tetrahydropyrimidine-2(1H)-thione 3e (>100% inhibition at 10 μM, IC50 = 1.2 μM) and 1-(4-tert-butylbenzyl)-tetrahydropyrimidine-2(1H)-thione 3f (>100% inhibition at 10 μM, IC50 = 0.76 μM) exhibited potent inhibitory effect against α-MSH-induced melanin production. Compounds 3 inhibit the biosynthesis of tyrosinase without affecting its catalytic activity in melanogenesis.  相似文献   

9.
A pair of isomeric isoflavonoid derivatives, Hirtellanines A (1) and B (2), has been isolated from the roots of Campylotropis hirtella (Franch.) Schindl. and their structures were elucidated on the basis of spectroscopic methods, with special emphasis on 1D and 2D NMR techniques. The in vitro assay showed that Hirtellanine A had strong B lymphocyte suppression activity (IC50: 0.06 μM) and T lymphocyte suppression activity (IC50: 0.92 μM). Hirtellanine B showed moderate B lymphocyte suppression activity (IC50: 3.00 μM) and T lymphocyte suppression activity (IC50: 9.55 μM). Due to the potent immunosuppressive activities and lower cytotoxicity, Hirtellanine A could be a promising lead towards novel immunosuppressive agents.  相似文献   

10.
A combinatorial series of novel quinazolin-4(3H)-ones were synthesised and their structures were established based on spectroscopic data (IR, NMR, EI-MS, and FAB-MS). The compounds were tested for inhibition of the zinc metalloproteinase thermolysin (TLN) utilizing a chemical array-based approach. Some of the compounds were found to inhibit TLN, with IC50 values ranging from 0.0115 μM (compound 3) to 122,637 μM (compound 29). Compound 3 [3-phenyl-2-(trifluoromethyl) quinazolin-4(3H)-one] (IC50 = 0.0115 μM) and compound 35 [3-(isopropylideneamino)-2,2-dimethyl-2,3-dihydroquinazolin-4 (1H)-one] (IC50 = 0.2477 μM) were found to be the most potent inhibitors.  相似文献   

11.
Fractionation guided by the cytotoxic activity of the methanolic extract of Veronica americana led to the isolation of two new iridoids identified as 4β-hydroxy-6-O-(p-hydroxybenzoyl)-tetrahydrolinaride (1) and 10-O-protocatechuyl-catalpol (2), together with four known aromatic acids, veratric acid (3) p-methoxybenzoic acid (4), p-hydroxybenzoic acid (5) and protocatechuic acid (6). The structure of these compounds was determined by spectroscopic analysis. Iridoid glycosides 1 and 2 showed selective cytotoxic activity against the human cancer cell lines HF-6 (IC50 = 0.031 and 0.066 μM, respectively) and PC-3 (IC50 = 0.721 and 0.801 μM, respectively), with less sensitivity in normal MRC-5 cells (IC50 = 77.103 and 1451.562 μM, respectively). Compound 1 was 9.9 times more potent than camptothecin against HF-6 cell line, while compound 2 was 4.7 times, more potent, against the same cell line, than camptothecin. The found biological efficacy of 1 and 2 allow us to propose these compounds as candidates for the development of effective anticancer therapeutic agents.  相似文献   

12.
A series of N-substituted amide linked triazolyl β-d-glucopyranoside derivatives (4a-l) were synthesized and their in vitro inhibitory activity against yeast α-glucosidase enzyme [EC.3.2.1.20] was assessed. Compounds 4e (IC50 = 156.06 μM), 4f (IC50 = 147.94 μM), 4k (IC50 = 127.71 μM) and 4l (IC50 = 121.33 μM) were identified as the most potent inhibitors for α-glucosidase as compared to acarbose (IC50 = 130.98 μM) under the same in vitro experimental conditions. Kinetic study showed that both 4e and 4f inhibit the enzyme in a competitive manner with p-nitrophenyl α-d-glucopyranoside as substrate. Molecular docking studies of 4e, 4f, 4k and 4l were also carried out using homology model of α-glucosidase to find out the binding modes responsible for the inhibitory activity. This study revealed that the binding affinity of compounds 4e, 4f, 4k and 4l for α-glucosidase were −8.2, −8.6, −8.3 and −8.5 kcal/mol respectively, compared to that of acarbose (−8.9 kcal/mol). The results suggest that the N-substituted amide linked triazole glycoconjugates can reasonably mimic the substrates for the yeast α-glucosidase.  相似文献   

13.
Quinone-methide triterpenes, celastrol (1), pristimerin (2), tingenone (3), and iguesterin (4) were isolated from Triterygium regelii and dihydrocelastrol (5) was synthesized by hydrogenation under palladium catalyst. Isolated quinone-methide triterpenes (14) and 5 were evaluated for SARS-CoV 3CLpro inhibitory activities and showed potent inhibitory activities with IC50 values of 10.3, 5.5, 9.9, and 2.6 μM, respectively, whereas the corresponding 5 having phenol moiety was observed in low activity (IC50 = 21.7 μM). As a result, quinone-methide moiety in A-ring and more hydrophobic E-ring assist to exhibit potent activity. Also, all quinone-methide triterpenes 14 have proven to be competitive by the kinetic analysis.  相似文献   

14.
Six 1,3-diphenylpropanes exhibiting inhibitory activities against both the monophenolase and diphenolase actions of tyrosinase were isolated from the methanol (95%) extract of Broussonetia kazinoki. These compounds, 16, were identified as kazinol C (1), D (2), F (3), broussonin C (4), kazinol S (5) and kazinol T (6). The latter two species (5 and 6) emerged to be new 1,3-diphenylpropanes which we fully spectroscopically characterized. The IC50 values of compounds (1, 35) for monophenolase inhibition were determined to range between 0.43 and 17.9 μM. Compounds 1 and 35 also inhibited diphenolase significantly with IC50 values of 22.8, 1.7, 0.57, and 26.9 μM, respectively. All four active tyrosinase inhibitors (1, 35) were competitive inhibitors. Interestigly they all mainfested simple reversible slow-binding inhibition against diphenolase. The most potent inhibitor, compound 4 diplayed the following kinetic parameters k3 = 0.0993 μM?1 min?1, k4 = 0.0048 min-1, and Kiapp = 0.0485 μM.  相似文献   

15.
A new compound govaniadine (1), along with three known tetrahydroprotoberberine-type alkaloids caseadine (2), caseamine (3), and protopine (4), were isolated from the plant Corydalis govaniana Wall. All alkaloids 14 exhibited a good urease enzyme inhibition with IC50 ± S.E.M. values of 20.2 ± 3.6, 38.9 ± 2.8, 66.7 ± 1.2, and 54.1 ± 1.2 μM, respectively, which are comparable to the standard inhibitor, acetohydroxamic acid (IC50 = 42.0 μM). None of these compounds showed inhibition against α-chymotrypsin. This is the first report of urease inhibiting tetrahydroprotoberberine-type alkaloids.  相似文献   

16.
The methanolic extract from fresh stems of Cistanche tubulosa (Orobanchaceae) was found to show hepatoprotective effects against d-galactosamine (d-GalN)/lipopolysaccharide (LPS)-induced liver injury in mice. From the extract, three new phenylethanoid oligoglycosides, kankanosides H1 (1), H2 (2), and I (3), were isolated together with 16 phenylethanoid glycosides (419) and two acylated oligosugars (20, 21). The structures of 13 were determined on the basis of spectroscopic properties as well as of chemical evidence. Among the isolates, echinacoside (4, IC50 = 10.2 μM), acteoside (5, 4.6 μM), isoacteoside (6, 5.3 μM), 2′-acetylacteoside (8, 4.8 μM), and tubuloside A (10, 8.6 μM) inhibited d-GalN-induced death of hepatocytes. These five isolates, 4 (31.1 μM), 5 (17.8 μM), 6 (22.7 μM), 8 (25.7 μM), and 10 (23.2 μM), and cistantubuloside B1 (11, 21.4 μM) also reduced TNF-α-induced cytotoxicity in L929 cells. Moreover, principal constituents (46) exhibited in vivo hepatoprotective effects at doses of 25–100 mg/kg, po.  相似文献   

17.
Continued interest in the chemistry of Ficus spp. led to the investigation of the figs and the roots of Ficus thonningii Blume. Two new flavonoids, thonningiol (1) and thonningiisoflavone (2) along with nineteen known compounds were isolated. β-Isoluteone (13) was isolated here for the first time from a natural source. Their structures were elucidated on the basis of spectroscopic evidence. Interestingly, thonningiisoflavone (2) and hydroxyalpinumisoflavone (21) showed strong DPPH radical scavenging activity with IC50 = 65.50 μM and 68.20 μM respectively compared to the standard BHA with IC50 = 44.20 μM. The methanolic extract of figs, taxifolin (14), conrauiflavonol (17) and shuterin (19) exhibited moderate antimicrobial activity against six micro-organisms with MIC below 1.5 mg/mL.  相似文献   

18.
Bioassay-guided separation of the South African plant Kniphofia ensifolia for antiplasmodial activity led to the isolation of two new anthraquinones, named kniphofiones A and B (3 and 4), together with three known bioactive anthraquinone monomers (1, 2 and 5), and four known bisanthraquinones (69). The structures of the two new compounds were elucidated based on analyses of their 1D and 2D NMR spectra and mass spectrometric data. The dimeric compounds 6 and 7 displayed the strongest antiplasmodial activity among all the isolated compounds, with IC50 values of 0.4 ± 0.1 and 0.2 ± 0.1 μM, respectively. The two new compounds displayed modest activities, with IC50 values of 26 ± 4 and 9 ± 1 μM, respectively. Due to the synthetic accessibility of the new compounds and the increased activity shown by the dimeric compounds, a structure–activity relationship study was conducted. As a result, one analogue of kniphofione B (4), the caffeic acid derivative of aloe-emodin, was found to have the highest activity among all the aloe-emodin derivatives, with an IC50 value of 1.3 ± 0.2 μM.  相似文献   

19.
Salvialeriol (1), a new abietane-type diterpene, was isolated from Salvia leriifolia Benth. (Salvia leriaefolia), along with two known abietane-type diterpenoids, 6-hydroxysalvinolone (2) and deacetylnemorone (3), and two known triterpenes, 2-acetoxylupeol (4), and lupine-2,3-diol (5). Compounds 2–5 are reported here for the first time from this species. Compound 4 was previously reported as a synthetic derivative of 5 and this is the first report of its isolation from a natural source. Compounds 2, 3 and 5 exhibited a potent antiproliferative activity against the prostate cancer cell lines (PC3) with IC50 of 3.9 ± 0.1, 6.2 ± 0.1 and 2.8 ± 0.1 μM, respectively, and cervical cancer cell lines (HeLa) with IC50 of 8.0 ± 0.3, 2.6 ± 0.1 and 2.7 ± 0.1 μM, respectively. Whereas compounds 1 and 4 showed moderate antiproliferative activities against the cell lines. Compounds 15 were also evaluated for the inhibition of α-chymotrypsin, a protease enzyme, and 2 exhibited a competitive inhibition of the enzyme (IC50 = 188.8 μM).  相似文献   

20.
A series of 23 3′,4′,5′-trimethoxychalcone analogues was synthesized and their inhibitory effects on nitric oxide (NO) production in LPS/IFN-γ-treated macrophages, and tumor cell proliferation has been investigated. 4-Hydroxy-3,3′,4′,5′-tetramethoxychalcone (7), 3,4-dihydroxy-3′,4′,5′-trimethoxychalcone (11), 3-hydroxy-3′,4,4′,5′-tetramethoxychalcone (14), and 3,3′,4′,5′-tetramethoxychalcone (15) were the most potent growth inhibitory agents on NO production, with an IC50 value of 0.3, 1.5, 1.3 and 0.3 μM, respectively. The tumor cells proliferation assay results revealed that several compounds exhibited potent inhibition activity against different cancer cell lines. The chalcone 15 was the most potent anti-proliferative compound in the series with IC50 values of 1.8 and 2.2 μM toward liver cancer Hep G2 and colon cancer Colon 205 cell lines, respectively. 2,3,3′,4′,5′-Pentamethoxychalcone (1), 3,3′,4,4′,5,5′-hexamethoxychalcone (3), 2,3′,4,4′,5,5′-hexamethoxychalcone (5), 2-hydroxy-3,3′,4′,5′-tetramethoxychalcone (10), 11 and 14 showed significant anti-proliferation actions in Hep G2 and Colon 205 cells with an IC50 values ranging between 10 and 20 μM. Among the tested agents, compound 7 showed selective NO production inhibition (IC50 = 0.3 μM), while has no effect on tumor cell proliferation (IC50 >100 μM). 3,3′,4,4′,5′-Pentamethoxychalcone (2) showed selective anti-proliferation effect in Hep G2 cells, in addition to its potent NO inhibition, however has no such response in Colon 205 cells. In contrast, 3-formyl-3′,4′,5′-trimethoxychalcone (22) showed moderate growth inhibition in Colon 205 cells, while has no such effect on NO production and Hep G2 cells proliferation. These results provide insight into the correlation between some structural properties of 3′,4′,5′-trimethoxychalcones and their in vitro anti-inflammatory and anti-cancer differentiation activity.  相似文献   

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