Search results for " medicinal"
showing 10 items of 590 documents
New phenolics, cytotoxicity and chemosystematic significance of Atriplex semibaccata
2019
Abstract The chemical characterization of the 70% hydromethanolic extract of Atriplex semibaccata (family: Chenopodiaceae) afforded a new methoxylated flavonol triglycoside, atrisemibaccatoside A (1), and a new lignanamide, (N-[(E)-m-hydroxycinnamoyl]tyramine (7), as well as, five known flavonols (2–6) and two lignanamides (8–9). The structures of the isolated compounds were established depending upon LR&HR-FAB-MS, 1D and 2D NMR spectroscopic analyses. The cytotoxic activity of the isolated compounds (1–4, and 7–9) was investigated. Compounds 7, 8 and 9 weakly inhibited the proliferation of leukemia CCRF-CEM cells with IC50 values of 78.5, 46.3, and 71.2 μg/ml, respectively, and exhibited n…
Triterpene saponins from the roots of Bupleurum spinosum Gouan
2020
Abstract Three previously undescribed triterpene saponins, and four known ones, were isolated from the EtOH/H2O extract of the roots of Bupleurum spinosum. Their structures were characterized using spectroscopic techniques including 1D and 2D NMR (1H, 13C, COSY, TOCSY, ROESY, HSQC, and HMBC) experiments and mass spectrometry as 3-O-β-D-glucopyranosyl-(1→6)-[β-D-glucopyranosyl-(1→2)]-[α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranosyl-3β,16β,23,28-tetrahydroxyolean-12-ene, 3-O-β-D-glucopyranosyl-(1→6)-[β-D-glucopyranosyl-(1→2)]-[α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranosyl-3β,16β,28-trihydroxy-23-oxoolean-12-ene, 3-O-β-D-glucopyranosyl-(1→6)-[α-L-rhamnopyranosyl(1→4)]-β-D-glucopyranosyl-3β,16β,2…
Stereoselective Synthesis of (+)-Boronolide
2002
The delta-lactone boronolide (+)-1, a pharmacologically active, naturally occurring product, has been synthesized in enantiopure form with L-erythrulose as the chiral starting material. The key steps of the synthesis were a highly stereoselective aldol-reduction one-pot sequence, an indium-mediated diastereoselective aldehyde allylation, and a ring-closing metathesis.
Cytotoxicity of an unprecedented brominated oleanolide and a new furoceramide from the Cameroonian spice, Echinops giganteus
2016
A preliminary study on Echinops giganteus (Asteraceae) showed that the methanolic extract has interesting cytotoxicities against a panel of cancer cell lines. From this extract, a lignan, a flavonoid and a polyacetylenic thiophene identified were three times less cytotoxic than the extract. In the search of the metabolites responsible for the bioactivity, a new harvested E. giganteus was subjected to a phytochemical study using chromatographic methods. In the course of the work, two new compounds: a brominated oleanolide (1) and a tetrahydrofurano-ceramide (2) were obtained along with β-amyrin acetate (3), 2-(penta-1,3-diynyl)-5-(4-hydroxybut-1-ynyl)-thiophene (4), 2-(penta-1,3-diynyl)-5-(3…
Two novel oxetane containing lignans and a new megastigmane from Paronychia arabica and in silico analysis of them as prospective SARS-CoV-2 inhibito…
2021
The chemical characterization of the extract of the aerial parts of Paronychia arabica afforded two oxetane containing lignans, paronychiarabicine A (1) and B (2), and one new megastigmane, paronychiarabicastigmane A (3), alongside a known lignan (4), eight known phenolic compounds (5–12), one known elemene sesquiterpene (13) and one steroid glycoside (14). The chemical structures of the isolated compounds were constructed based upon the HRMS, 1D, and 2D-NMR results. The absolute configurations were established via NOESY experiments as well as experimental and TDDFT-calculated electronic circular dichroism (ECD). Utilizing molecular docking, the binding scores and modes of compounds 1–3 tow…
Eliciting callus culture for production of hepatoprotective flavonoids and phenolics from Sequoia sempervirens (D. Don Endl)
2020
The aim of our study is to estimate the hepatoprotective effects of the ethanolic extract of the leaves of Sequoia sempervirens by determination of liver biomarkers (ALT, AST, total bilirubin and albumin in serum) and by histopathological examinations using thioacetamide-induced (TAA) liver injury model. Concurrent administration of ethanolic extracts of S. sempervirens leaves improved the alterations in liver morphology where it was a potent protector of the liver. The potential of L-phenylalanine and silver nitrate as chemical elicitors as well as UV radiation as a physical elicitor on flavonoid production in callus culture of S. sempervirens were emphasized. Murashige and Skoog’s medium …
Synthesis of plagiochiline N from santonin.
2001
This article reports the transformation of O-acetylisophotosantonin, obtained by photochemical rearrangement of santonin, into plagiochiline N, an ent-2,3-secoaromadendrane isolated from Plagiochila ovalifolia. The synthesis was carried out in a sequence involving as the key steps (a) the substitution of the lactone moiety by a gem-dimethylcyclopropane ring through a synthetic intermediate having a C(6)-C(7) double bond and (b) the ozonolysis of the C(2)-C(3) bond followed by cyclization to the dihydropyran ring characteristic of plagiochiline N. Spectroscopic data of the synthetic product fully coincided with the reported data for the natural product.
In vivo anti-inflammatory activity of saponins from Bupleurum rotundifolium
2001
Seven oleanane-type triterpene saponins were isolated from the methanolic extract of the aerial parts of Bupleurum rotundifolium. They were identified on the basis of their spectral data as 3-O-[alpha-L-rhamnopyranosyl (1--2)-beta-D-glucopyranosyl (1--2)-beta-D-glucopyranosyl]-28-O-[beta-D-glucopyranosyl (1--2)-beta-D-glucopyranosyl] echinocystic acid (saponin 1), 3-O-[alpha-L-rhamnopyranosyl (1--2)-beta-D-glucopyranosyl (1--2)-beta-D-fucopyranosyl] 11-methoxy-primulagenin A (saponin 2), rotundioside E (saponin 3), rotundioside F (saponin 4), 3beta-sulfate, 28-O-[beta-D-glucopyranosyl (1--6)-beta-D-glucopyranosyl (1--2)-beta-D-glucopyranosyl (1--2)-beta-D-glucopyranosyl] ester of primulagen…
Molecular hydrogen (H 2 ) as a potential treatment for acute and chronic fatigue
2020
Many diseases as well as acute conditions can lead to fatigue, which can be either temporary or chronic in nature. Acute fatigue develops frequently after physical exercise or after alcohol hangover, whereas microbial infections such as influenza or COVID-19 and chronic diseases like Parkinson's disease or multiple sclerosis are often associated with chronic fatigue. Oxidative stress and a resulting disturbance of mitochondrial function are likely to be common denominators for many forms of fatigue, and antioxidant treatments have been shown to be effective in alleviating the symptoms of fatigue. In this study, we review the role of reactive oxygen and nitrogen species in fatigue and the an…
A new ceramide from the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl.
2020
A new ceramide is being reported herein together with six known compounds from the methanol extract of the leaves of Lannea schimperi (Hochst. ex A.Rich.) Engl. The metabolites were obtained through repeated open column chromatography and were characterized by spectroscopic and spectrometric techniques. The radical-scavenging activity of the crude extract and isolated compounds was evaluated using the DPPH radical. The obtained results suggest the studied species as prominent candidate to fight reactive oxygen species (ROS).