1. |
- Amountzias, Vaios, et al.
(author)
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Cyclopeptide alkaloids from the Greek shrub Paliurus spina-christi and their in silico binding affinity to Dipeptidyl Peptidase IV
- 2024
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In: NATURAL PRODUCT RESEARCH. - 1478-6419 .- 1478-6427.
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Journal article (peer-reviewed)abstract
- A new cyclopeptide alkaloid, spinachristene A (1), along with two previously described, sanjoinenine (2) and oxyphylline C (3), were isolated from the fruits of Paliurus spina-christi Mill. All three metabolites are being isolated for the first time from the genus Paliurus. A model for the in silico binding affinity of compounds 1-3 to Dipeptidyl Peptidase IV (DPP4), which is related to type 2 diabetes (T2D), was developed. According to our model, compounds 1-3 were ranked in positions 9/12, 11/12 and 8/12, respectively and are predicted to exhibit significant affinity to DPP4, in the range of low 2-digit mu M.
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2. |
- Ashitani, Tatsuya, et al.
(author)
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Reaction mechanism of direct episulfidation of caryophyllene and humulene
- 2008
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In: Natural Product Research. - : Informa UK Limited. - 1478-6419 .- 1478-6427. ; 22:6, s. 495-498
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Journal article (peer-reviewed)abstract
- Direct episulfidations of caryophyllene or humulene with elemental sulfur were examined by means of gas chromatography. Caryophyllene-6,7-episulfide was formed at an early stage in a reaction of the caryophyllene and elemental sulfur at 120C. Caryophyllene-3,6-sulfide and polymer compounds were formed after the episulfidation. Formations of the these compounds were related to the disappearance of the caryophyllene-6,7-episulfide. Isomerization from the caryophyllene to isocaryophyllene was also observed during the reaction. In the reaction of humulene with elemental sulfur, humulene-6,7-episulfide was initially produced and then converted to humulene-9,10-episulfide. It was assumed that the polymer compound in the reaction of humulene with sulfur was related to the disappearance of the both humulene episulfides.
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3. |
- El-Seedi, Hesham R
(author)
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Antimicrobial triterpenes from Poulsenia armata Miq. Standl.
- 2005
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In: Natural Product Research. - : Informa UK Limited. - 1478-6419 .- 1478-6427. ; 19:2, s. 197-202
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Journal article (peer-reviewed)abstract
- Crude petroleum ether extract from the bark of Poulsenia armata showed antimicrobial activity. Activity-guided fractionation led to the isolation and structure elucidation of two active new triterpene derivatives, the stearate of glut-5-en-3beta-ol (1) and 3beta,28-diacetoxyurs-12-ene (4), for the first time as naturally occurring compounds. Compound 4 has previously been synthesized. The structures were determined by 1D- and 2D-NMR spectroscopy, mass spectrometry and chemical transformations. This is the first report on the chemistry and pharmacology of the genus.
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4. |
- Forestrania, Roshamur Cahyan, et al.
(author)
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Secondary metabolites from Garcinia daedalanthera Pierre leaves (Clusiaceae)
- 2022
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In: Natural Product Research. - : Taylor & Francis Group. - 1478-6419 .- 1478-6427. ; 36:1, s. 207-213
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Journal article (peer-reviewed)abstract
- Two new glycerol esters, (S)-2-hydroxy-3-(octanoyloxy)propyl tetracosanoate (1) and (S)-3-(((S)-11-acetoxy octadecanoyl)oxy)propane-1,2-diyl diacetate (2), and eight known compounds, docosanedioic acid (3), 2,5-dimethylnonadecane (4), lupeol (5), stigmasterol (6), β-sitosterol (7), heptadecanoic acid (8), hexanedioic acid, 1,6-bis[(2R)-ethylhexyl] ester (9), and 1,3-di-O-[2',2'-di-(p-phenylene)] (10) were isolated from the leaves of Garcinia daedalanthera Pierre, collected from Indonesia. Structural analysis of the isolates was performed using 1 D- and 2 D-NMR, LC- and GC-MS, IR, polarimetry, and UV-visible spectroscopic methods. Cytotoxicity assessments, as well as reactive oxygen species (ROS) analysis of the isolates, were also completed. Lupeol was the only compound found active with an IC50 value of 19.2 µM against HT-29 colon cancer cells. Significant ROS inhibition and induction activity was observed for compounds 4 and 8, respectively.
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5. |
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6. |
- Gomaa, Mohamed N., et al.
(author)
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Antibacterial effect of the red sea soft coral Sarcophyton trocheliophorum
- 2016
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In: Natural Product Research. - : Informa UK Limited. - 1478-6419 .- 1478-6427. ; 30:6, s. 729-734
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Journal article (peer-reviewed)abstract
- The marine soft corals Sarcophyton trocheliophorum crude extracts possessed antimicrobial activity towards pathogenic bacterial strains, i.e. Bacillus cereus, Salmonella typhi, Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Bioassay-guided fractionation indicated that the antimicrobial effect was due to the presence of terpenoid bioactive derivatives. Further biological assays of the n-hexane fractions were carried out using turbidity assay, inhibition zone assay and minimum inhibitory concentration for investigating the growth-inhibition effect towards the Gram-positive and Gram-negative bacteria. The fractions were screened and the structure of the isolated compound was justified by interpretation of the spectroscopic data, mainly mass spectrometry (GC-MS). The structure was assigned as (5S)-3-[(3E,5S)-5-hydroxy-3-hepten-6-yn-1-yl]-5-methyl-2(5H)-furanone and was effective at concentrations as low as 0.20mg/mL. The above findings, in the course of our ongoing research on marine products, may implicate that the profound anti-microbial activity of the S. trocheliophorum soft corals, inhabiting the red sea reefs, is attributed to the presence of growth-inhibiting secondary metabolites mainly terpenoids.
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7. |
- Ibrahim, Nabaweya Ali, et al.
(author)
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Phytochemical investigation and hepatoprotective activity of Cupressus sempervirens L. leaves growing in Egypt.
- 2007
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In: Natural Product Research. - : Informa UK Limited. - 1478-6419 .- 1478-6427. ; 21:10, s. 857-866
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Journal article (peer-reviewed)abstract
- Three phenolic compounds cosmosiin, caffeic acid, and p-coumaric acid were isolated for the first time from the leaves of Cupressus sempervirens L., together with cupressuflavone, amentoflavone, rutin, quercitrin, quercetin, myricitrin. The isolated compounds were identified using (1)H- and (13)C-NMR spectra. The hepatoprotective activity of the MeOH extract was carried out in liver homogenate of normal and CCl(4)-treated rats; a significant decrease in glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, cholesterol level, and triglycerides, while a significant increase in the total protein level, was observed after the oral administration of MeOH extract. The free radical scavenging activity against stable 2,2-diphenyl-2-picrylhydrazyl (DPPH*) was measured for MeOH extract and some of the isolated phenolic compounds in comparison with alpha-tocopherol and butylated hydroxy toluene as standard antioxidants using ESR technique, showed high antioxidant activity for quercetin, rutin, caffeic acid, and p-coumaric acid.
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8. |
- Jassbi, Amir Reza, et al.
(author)
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Cytotoxic abietane-type diterpenoids from roots of Salvia spinosa and their in Silico pharmacophore modeling
- 2022
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In: Natural Product Research. - : Informa UK Limited. - 1478-6419 .- 1478-6427. ; 36:12, s. 3183-3188
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Journal article (peer-reviewed)abstract
- The roots of Salvia spinosa L. (Lamiaceae) were extracted withhexane, dichloromethane (DCM) and ethyl acetate. The DCMextract exhibited cytotoxic activity (IC50 32.7 mg/mL) against MFC7 breast cancer cell line in MTT colorimetric bioassay. Ferruginol(1), taxodione (2), 12-deoxy-6-hydroxy-6,7-dehydroroyleanone (3),14-deoxycoleon U (4), 15-deoxyfuerstione (5) and taxodone (6)were isolated from the DCM roots extract. Their structures wereelucidated by a combination of spectroscopic analyses includingEIMS and 1H- and 13C NMR spectra. The cytotoxicity of compound3 was determined against MCF-7 and K562 cell lines and compared with the other compounds. A pharmacophore model wasbuilt based on potent input compounds to resolve importantpharmacophore features responsible for cytotoxic activity of theisolated compounds
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9. |
- Nord, Christina, et al.
(author)
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Tetramic acid based alkaloids from Aspergillus amoenus Roberg strain UP197-antibiotic properties and new pyranterreones
- 2022
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In: Natural Product Research. - : Informa UK Limited. - 1478-6419 .- 1478-6427. ; 36:4, s. 967-973
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Journal article (peer-reviewed)abstract
- The fungus Aspergillus amoenus Roberg strain UP197 was shown to produce antibacterial tetramic acid based alkaloids. Two new compounds, pyranterreone I and J (1 and 2), were isolated and characterized, in addition to the known compounds cordylactam, 7-hydroxycordylactam, pyranterreone C, D, F and G. Neither the pyranterreones nor the cordylacctams had previously been tested for antimicrobial activity. Thus, all isolated compounds were tested against a panel of clinically important bacteria and fungi. Pyranterreone C was active against Gram-positive and Gram-negative bacteria, with minimal inhibitory concentrations (MIC) between 1 and 8 mu g/mL, whereas the MICs for all other compounds were >32 mu g/mL. Pyranoterreone C was cytotoxic towards HepG2 cells, and since pyranterreone C reacted rapidly with the nucleophile cysteine, it is likely that the observed antibacterial activity is due to the chemical reactivity rather than enzymatic affinity, making it unsuitable for development as an antibacterial drug.
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10. |
- Sohretoglu, Didem, et al.
(author)
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Antioxidant secondary metabolites from Geranium lasiopus Boiss. & Heldr.
- 2012
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In: Natural Product Research. - : Informa UK Limited. - 1478-6419 .- 1478-6427. ; 26:13, s. 1261-1264
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Journal article (peer-reviewed)abstract
- Chromatographic studies on the EtOAc soluble portion of the MeOH extract of Geranium lasiopus led to the isolation of eight flavonoids (kaempferol (1), quercetin (2), quercetin 3-O-beta-glucopyranoside (3), quercetin 3-O-beta-galactopyranoside (4), kaempferol 3-O-alpha-rhamnopyranosyl-(1 -> 6)-beta-glucopyranoside (5), quercetin 3-O-alpha-rhamnopyranosyl-(1 -> 6)-beta-glucopyranoside (6), kaempferol 3-O-alpha-rhamnopyranosyl-(1 -> 2)-beta-glucopyranoside (7) and quercetin 3-O-alpha-rhamnopyranosyl-(1 -> 2)-beta-glucopyranoside (8)), two simple phenolic compounds (gallic acid (9) and its methyl ester (10)) and a hydrolysable tannin (pusilagin (11)). The structures of the compounds were elucidated by 1- and 2-dimensional NMR techniques (H-1, C-13, COSY, HMBC, HMQC) and ESI-TOF-MS spectrometry. Inhibitory effects on H2O2-induced lipid peroxidation in human red blood cells of the different extracts of G. lasiopus, as well as isolated compounds, were investigated. All tested compounds showed comparable or higher activity than that of ascorbic acid and trolox.
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