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3-Oxo-12alpha-hydroxyfriedelane from Maytenus gonoclada: structure elucidation by (1)H and (13)C chemical shift assignments and 2D-NMR spectroscopy. | LitMetric
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3-Oxo-12alpha-hydroxyfriedelane from Maytenus gonoclada: structure elucidation by (1)H and (13)C chemical shift assignments and 2D-NMR spectroscopy.

Mauro Lúcio G Oliveira Lucienir Pains Duarte Grácia Divina F Silva Sidney Augusto Vieira Filho Vagner Fernandes Knupp Fernando Gomes P Alves

Magn Reson Chem

NEPLAM - Departamento de Química, ICEx, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, CEP 31270-901, Belo Horizonte, Minas Gerais, Brazil.

Published: October 2007

The compounds 3-oxofriedelane (1), 3beta-hydroxyfriedelane (2), 3,11-dioxofriedelane (3), 3,16-dioxofrie delane (4) and 3-oxo-12alpha-hydroxyfriedelane (5) were isolated from the hexane extract of Maytenus gonoclada Mart. (Celastraceae) leaves. Structural formula and the stereochemistry of the new pentacyclic triterpene 3-oxo-12alpha-hydroxyfriedelane (5) were established through (1)H and (13)C NMR and DEPT 135 spectral data including 2D experiments (HMBC, HMQC, COSY, and NOESY) and mass spectrometry (GC-MS).

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http://dx.doi.org/10.1002/mrc.2062DOI Listing

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