High Resolution Nuclear Magnetic Resonance
Mostrando 1-12 de 145 artigos, teses e dissertações.
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1. Friedelane Triterpenes with Cytotoxic Activity from the Leaves of Maytenus quadrangulata (Celastraceae)
Three new triterpenes, 3,4-seco-3,11β-epoxyfriedel-4(23)-en-3β-ol (1), friedelan-3α,11β diol (2), 7β,26-epoxyfriedelan-3a,7a-diol (3), a mixture of two new triterpenes 3α-hydroxyfriedelan-29-yl palmitate (4) and 3α-hydroxyfriedelan-29-yl stearate (5) and eleven known compounds were obtained from the hexane extract of Maytenus quadrangulata leaves. The
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Anti-Hyperglycemic Activities, Molecular Docking and Structure-Activity Relationships (SARs) Studies of Endiandric Acids and Kingianins from Endiandra kingiana
Diabetes has become a severe chronic disease worldwide with patients significantly increasing daily. Due to the side effects of insulin and oral hypoglycaemic agents employed in diabetes treatment, scientists are working hard to develop alternative approaches from natural plants that inhibit α-amylase and α-glucosidase. Consequently, by performing a phytoc
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. Synthesis of Eugenol-Fluorinated Triazole Derivatives and Evaluation of Their Fungicidal Activity
Eugenol (C10H12O2, 4-allyl-2-methoxyphenol) is a phenolic natural product that has several biological activities and possibilities of applications. It is herein described the synthesis of eugenol-fluorinated triazole derivatives and evaluation of their fungicidal activity. The reaction of eugenol with epichlorohydrin resulted in the preparation of (±)-2-((4
Journal of the Brazilian Chemical Society. Publicado em: 2022
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4. Capital, ideologia e uma história do mundo sob o prisma da desigualdade
The phytochemical reinvestigation from the heartwood of the extracts of Cordia glazioviana led to the isolation of four still undescribed hydroquinones derivatives designated as cordiaquinol D (1), cordiaquinol E (2), (10R)-10,11-dihydrofuran-1,4-dihydroxy-globiferin (3) and 2-[(1’E,6’E)-3’,8’- dihydroxy-3’,7’-dimethylocta-1’,6’-dienyl]-benze
Econ. soc.. Publicado em: 2021-07
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5. Anti-Inflammatory Meroterpenoids of Cordia glazioviana (Boraginaceae)
The phytochemical reinvestigation from the heartwood of the extracts of Cordia glazioviana led to the isolation of four still undescribed hydroquinones derivatives designated as cordiaquinol D (1), cordiaquinol E (2), (10R)-10,11-dihydrofuran-1,4-dihydroxy-globiferin (3) and 2-[(1’E,6’E)-3’,8’- dihydroxy-3’,7’-dimethylocta-1’,6’-dienyl]-benze
J. Braz. Chem. Soc.. Publicado em: 2021-07
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6. Alcoholmeter as a Simple and Accessible Way for Ethanol Determination in Alcohol-Based Hand Sanitizers
Expensive and complex methodologies are available to determine the ethanol concentration in alcohol gel samples. The aim of this article was to demonstrate that alcoholmeter could be used as an alternative method to determine ethanol in gel formulations. Alcohol gel samples were produced using: hydroxypropylmethylcellulose (HPMC), hydroxyethylcellulose (HEC)
J. Braz. Chem. Soc.. Publicado em: 2021-06
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7. Electrochemical Preparation and Evaluation of Cytotoxic Activity of Methoxyl-oxo-biseugenol, a New Oxidized Derivative of Biseugenol
Electrochemical procedures have emerged as a powerful tool for the synthesis of complex organic molecules including transformation of natural products. In this study, the electrosynthesis of biseugenol in MeOH afforded one new oxidized derivative, which was characterized as methoxyl-oxo-biseugenol (MOB) by nuclear magnetic resonance (NMR) and electrospray io
J. Braz. Chem. Soc.. Publicado em: 2021-05
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8. Antileishmanial Acetylene Fatty Acid and Acetogenins from Seeds of Porcelia macrocarpa
In the present work five acetylene derivatives (1-5), including three unknowns (1, 3 and 4), were isolated from seeds of Porcelia macrocarpa (Annonaceae). The structures of isolated compounds were determined as docos-13-yn-21-enoic acid (1), 3-hydroxy-4-methylene-2-(eicos-11’-yn-19’-enyl)but-2-enolide (2), 3-hydroxy-4-methylene-2-(octadec-9’-yn-17’-e
J. Braz. Chem. Soc.. Publicado em: 2021-02
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9. Synthesis and Antioxidant and Antimicrobial Properties of β-Hydroxy Sulfides, Sulfoxides, and Sulfones Derived from Cardanol and Glycerol Derivatives
Natural and synthetic sulfur-bearing organic compounds have many applications in medicinal chemistry. This article reports the preparation of amphiphilic β-hydroxy sulfides, sulfoxides, and sulfones derived from cardanol and glycerol. Thiolysis of cardanol epoxide 3 with various thiols (4a-4j) in ethanol or water yielded the corresponding β-hydroxy sulfide
J. Braz. Chem. Soc.. Publicado em: 2020-12
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10. One-Step Isolation of Monoterpene Indole Alkaloids from Psychotria leiocarpa Leaves and Their Antiviral Activity on Dengue Virus Type-2
The leaf MeOH extract of Psychotria leiocarpa (Rubiaceae) showed in vitro non-cytotoxic and anti-dengue virus serotype 2 (DENV2) activity in human hepatocarcinoma cell lineage (HepG2). A one-step and cost-effective reversed-phase solid-phase extraction method based on high-performance liquid chromatography (HPLC) parameters allowed the isolation, directly fr
J. Braz. Chem. Soc.. Publicado em: 2020-10
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11. Synthesis, in silico Study, Theoretical Stereochemistry Elucidation and Antifungal Activity of New Imides Derived from Safrole
Ten imides derived from safrole, 4a-4j, were synthesized and their structures were fully characterized by infrared (IR) spectroscopy, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy and high resolution mass spectrometry (HRMS) analysis. Among the ten imides studied, eight are new. The compounds were evaluated in an in silico study and showed strong
J. Braz. Chem. Soc.. Publicado em: 2020-10
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12. Dereplication of Aporphine Alkaloids by UHPLC-HR-ESI-MS/MS and NMR from Duguetia lanceolata St. -Hil (Annonaceae) and Antiparasitic Activity Evaluation
Although the genus Duguetia is well known for producing alkaloids as chemical constituents, there are no reports of alkaloids identified in the species D. lanceolata. Thus, aiming to identify the chemical composition of this species, the dereplication of alkaloidic phase was performed by use of ultra-high performance liquid chromatography high resolution ele
J. Braz. Chem. Soc.. Publicado em: 2020-09