Investigation of Uña De Gato I. 7-Deoxyloganic acid and 15N NMR spectroscopic studies on pentacyclic oxindole alkaloids from Uncaria tomentosa
| Autor: | D. Chuck Dunbar, Ikhlas A. Khan, Riaz A. Khan, Markus Ganzera, Ilias Muhammad |
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| Rok vydání: | 2001 |
| Předmět: |
Indoles
Magnetic Resonance Spectroscopy Stereochemistry Rubiaceae Plant Science Horticulture Biology Pharmacognosy Biochemistry chemistry.chemical_compound Alkaloids Glucoside Tumor Cells Cultured Uncaria tomentosa Humans Iridoids Oxindole Molecular Biology Nitrogen Isotopes Alkaloid Biological activity General Medicine Carbon-13 NMR biology.organism_classification chemistry Two-dimensional nuclear magnetic resonance spectroscopy |
| Zdroj: | Phytochemistry. 57:781-785 |
| ISSN: | 0031-9422 |
| DOI: | 10.1016/s0031-9422(01)00043-7 |
| Popis: | The C-8-( S ) isomer of deoxyloganic acid (7-deoxyloganic acid), together with β-sitosteryl glucoside, five known stereoisomeric pentacyclic oxindole alkaloids and the tetracyclic oxindole isorhyncophylline, were isolated from the inner bark of Uncaria tomentosa . Structures of the isolated compounds were based on 1 H and 13 C NMR data, mainly 2D NMR experiments, including 1 H– 13 C HMBC and 1 H– 1 H NOESY correlation. Furthermore, the hitherto unreported 15 N chemical shifts of the isomeric oxindole alkaloids, using 1 H– 15 N HMBC experiments, were utilized to facilitate their characterization. Uncarine D showed weak cytotoxic activity against SK-MEL, KB, BT-549 and SK-OV-3 cell lines with IC 50 values between 30 and 40 μg/ml, while uncarine C exhibited weak cytotoxicity only against ovarian carcinoma (IC 50 at 37 μg/ml). |
| Databáze: | OpenAIRE |
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