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1.
Int J Med Mushrooms ; 25(12): 43-53, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37947063

RESUMEN

Chemical investigation of the polypore fungus Fistulina hepatica resulted in the isolation of five compounds, including four new polyacetylenic fatty acid derivatives - isocinnatriacetin B (1), isocinnatriacetin A (2), cinna-triacetin C (3) and ethylcinnatriacetin A (4) together with one known polyacetylene fatty acid derivative - cinnatriacetin A (5). The structures were elucidated using spectroscopic methods (UV, NMR, HR-ESIMS) along with comparison to literature data. Antibacterial activity screening of compounds 1-5 against ESKAPE bacterial strains in vitro with zones of inhibition (ZOI) was performed and MIC values were established for the most active compounds (3 and 4). Together with that morphological and growth parameters under solid-phase cultivation were also researched.


Asunto(s)
Agaricales , Basidiomycota , Polímero Poliacetilénico/farmacología , Basidiomycota/química , Antibacterianos , Poliinos/farmacología , Ácidos Grasos , Estructura Molecular
2.
Fitoterapia ; 171: 105697, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37797794

RESUMEN

Two previously undescribed isoquinoline alkaloids, bracteatinine (1) and isogroenlandicine (2), together with four known alkaloids - coptisine (3), dehydrocorydaline (4), palmatine (5) and jatrorrhizine (6) were isolated from the aerial parts of Corydalis bracteata (Steph. Ex. Willd.) Pers. The structures of the compounds were elucidated using 1D and 2D NMR data along with HRESI-MS. The isolated new compounds bracteatinine and isogroenlandicine are close structural derivatives and isomers of corgoine and groenlandicine, respectively. Bracteatinine is also notable, being a representative of the rare 2-benzylisoquinoline alkaloids. Many natural products isolated from different plants are used as adjuvants, in addition to standard chemotherapy, in treatment of different cancers. Cancer-associated thrombosis remains a common complication and leading cause of mortality for cancer patients. Because platelets play the key role in thrombotic complications, we investigated effects of the isolated alkaloids 1-6 on platelet reactivity and showed that they did not significantly affect platelet function.


Asunto(s)
Alcaloides , Corydalis , Neoplasias , Humanos , Corydalis/química , Estructura Molecular , Alcaloides/farmacología , Alcaloides/química , Isoquinolinas/farmacología , Isoquinolinas/química
3.
Nat Prod Res ; : 1-10, 2023 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-37004996

RESUMEN

Chemical investigation of the hydnoid fungus Sarcodontia setosa resulted in the isolation of five compounds, including two new sarcodontic acid derivatives - setosic acid (1) and 7,8-dehydrohomosarcodontic acid (2) along with three known benzoquinone pigments - sarcodontic acid (3), 4,5-dehydrosarcodontic acid (4) and dihydrosarcodontic acid (5). The structures were elucidated using spectroscopic methods (UV, NMR and HR-ESIMS). The biosynthetic relationship of the isolated compounds is proposed and discussed. Antibacterial activity screening of compounds 1-5 against ESKAPE bacterial strains in vitro with zones of inhibition was performed and MIC values were established for the most active compounds (3 and 5).

4.
Nat Prod Res ; 36(20): 5142-5147, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33949278

RESUMEN

A new dihydrochalcone, 2',4'-dimethoxydihydrochalcone (1), together with 7 known compounds, 2',4'-dihydroxydihydrochalcone (2), 2'-hydroxy-4'-methoxydihydrochalcone (3), 2'-hydroxy-4'-methoxychalcone (4), 1-(3,5-dihydroxy-4-methoxyphenyl)-2-(3-hydroxyphenyl) ethane (5), 2,3,4,7-tetramethoxy-9,10-dihydrophenanthrene (6), 5-hydroxy-2,3,4-trimethoxy-9,10-dihydrophenanthrene (7) and 5,7-dihydroxy-6,8-dimethyl flavanone (8) were isolated from the shoots of Empetrum nigrum L. The structures of these compounds were elucidated using 1D and 2D NMR experiments along with HR-ESI-MS. Compound 6 is reported for the genus Empetrum for the first time.[Formula: see text].


Asunto(s)
Chalconas , Ericaceae , Flavanonas , Ericaceae/química , Etano , Estructura Molecular
5.
Nat Prod Res ; 36(21): 5499-5507, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34935543

RESUMEN

Two undescribed (1-2) and five known cyclic diarylheptanoids (3-7) were isolated from the false heartwood of white birch (Betula pubescens Ehrh.). All structures were elucidated through extensive 1D and 2D NMR experiments and HR-ESI-MS data, along with comparison of their spectroscopic data with those reported in the literature. The two new cyclic diarylheptanoids are betuladiol (1) and betulondiol (2). Extracts from false heartwood were evaluated for their antimicrobial activity against Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis, Staphylococcus aureus and Cutibacterium acnes together with their antifungal activity against Candida albicans and Candida glabrata.


Asunto(s)
Betula , Diarilheptanoides , Diarilheptanoides/química , Extractos Vegetales/química , Staphylococcus aureus , Escherichia coli
6.
Lasers Surg Med ; 53(8): 1122-1131, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33450786

RESUMEN

BACKGROUND AND OBJECTIVE: A novel dual-stage method for active laser drug delivery (DSLADD) in the treatment of nail diseases is being presented. This method includes sequentially performed microporation of the nail with submillisecond pulses of Er:YLF laser radiation through a layer of an aqueous solution of drug deposited on the nail surface (Stage 1) and exposure this layer to the same laser radiation to deliver drug under the nail plate (Stage 2). The delivery of methylene blue (MB) as one of the possible drugs in the treatment of nail diseases is investigated. The influence of the thickness of the MB layer, as well as the energy and number of applied laser pulses, on the rate of active laser delivery is discussed. To illustrate the possible effect of delivery on the drug delivered, special attention is paid to the deformation of the extinction spectrum of MB solution after laser irradiation. STUDY DESIGN/MATERIALS AND METHODS: Diode-pumped Er:YLF laser was used for DSLADD. The process of DSLADD under the nail plate was investigated using digital video microscopy. For different values of the thickness of MB solution layer applied to the nail plate and the energy of laser pulses, the number of laser pulses required to create a single through a microchannel in the nail plate and the number of laser pulses required to deliver the solution to the ventral side of the nail plate after its microporation were registered. The mass and the dose of MB solution penetrated under the nail plate, and the rate of MB solution delivery through a single microchannel was determined. Investigation of the influence of Er:YLF laser radiation parameters on the extinction spectrum of the drug was performed using a fiber spectrometer. The extinction spectra of the 0.001% aqueous solution of MB were recorded before and after exposure to a different number of Er:YLF laser pulses with the energy of 1-4 mJ. RESULTS: It was found that the minimum number of laser pulses required for active Er:YLF laser drug delivery under the nail corresponds to the MB layer thickness of 100 µm and the laser pulse energy of 4 mJ. It is shown that in this case, the rate of active laser delivery of MB solution reaches 0.26 ± 0.03 mg/pulse. The radiation of the Er:YLF laser affects the shape of the extinction spectrum of the aqueous solution of MВ, which is associated with the transition of the dye from the monomeric to dimeric state. Depending on the laser pulse energy, the fraction of a certain conformational state in the aqueous MB solution can decrease or increase, stimulating a possible change in its photodynamic and antiseptic activity. CONCLUSION: For the first time, a novel DSLADD through the nail has been described and investigated in vitro. It was demonstrated that at Er:YLF laser pulse repetition rate of f = 30 Hz, microporation of the nail plate and drug delivery through a single microchannel will be about 1.5 s. Lasers Surg. Med. © 2021 Wiley Periodicals LLC.


Asunto(s)
Láseres de Estado Sólido , Preparaciones Farmacéuticas , Sistemas de Liberación de Medicamentos
7.
Biomed Opt Express ; 10(7): 3232-3240, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31467776

RESUMEN

Active Er-laser drug delivery under the nail plate using a drug-impregnated gel containing liquid methylene blue clusters is demonstrated for the first time. The effect of the agar-agar concentration in the gel and the gel plate thickness on the number of Er:YLF-laser pulses required for formation of a through microhole in the gel and in the nail plate with subsequent active drug delivery is discussed. The influence of the laser pulse energy, the gel plate thickness, and the external pressure applied to the gel on the rate of delivery of methylene blue under the nail plate through a single microhole in it is investigated. It is shown that with a laser pulse energy of 4.0 ± 0.1 mJ, the delivery rate can reach 0.024 ± 0.004 mg/pulse.

8.
Inorg Chem ; 55(7): 3351-63, 2016 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-26967379

RESUMEN

The noncovalent intermolecular interactions (π-π stacking, metallophilic bonding) of the cyclometalated complexes [Pt(NCN)L](+)X(-) (NCN = dipyridylbenzene, L = pyridine (1), acetonitrile (2)) are determined by the steric properties of the ancillary ligands L in the solid state and in solution, while the nature of the counterion X(-) (X(-) = PF6(-), ClO4(-), CF3SO3(-)) affects the molecular arrangement of 2·X in the crystal medium. According to the variable-temperature X-ray diffraction measurements, the extensive Pt···Pt interactions and π-stacking in 2·X are significantly temperature-dependent. The variable concentration (1)H and diffusion coefficients NMR measurements reveal that 2·X exists in the monomeric form in dilute solutions at 298 K, while upon increase in concentration [Pt(NCN)(NCMe)](+) cations undergo the formation of the ground-state oligomeric aggregates with an average aggregation number of ∼3. The photoluminescent characteristics of 1 and 2·X are largely determined by the intermolecular aggregation. For the discrete molecules the emission properties are assigned to metal perturbed IL charge transfer mixed with some MLCT contribution. In the case of oligomers 2·X the luminescence is significantly red-shifted with respect to 1 and originates mainly from the (3)MMLCT excited states. The emission energies depend on the structural arrangement in the crystal and on the complex concentration in solution, variation of which allows for the modulation of the emission color from greenish to deep red. In the solid state the lability of the ligands L leads to vapor-induced reversible transformation 1 ↔ 2 that is accompanied by the molecular reorganization and, consequently, dramatic change of the photophysical properties. Time-dependent density functional theory calculations adequately support the models proposed for the rationalization of the experimental observations.

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