Chalcone Dimers Research Articles

Cyclobutanes from Combretum albopunctatum

A dichloromethane extract of the aerial parts of Combretum albopunctatum Suesseng afforded five phenolic compounds—three known flavonoids and two novel cyclobutane chalcone dimers. The chemical structures were determined by standard spectroscopic techniques and the structure and relative stereochemistry of one chalcone dimer, rel-(1α,2β)-di-(2,6-dimethoxy-4-hydroxy)-benzoyl- rel-(3α,4β)-diphenylcyclobutane, were confirmed by single crystal X-ray diffraction.

Structural elucidation and total assignment of the 1H and 13C NMR spectra of new chalcone dimers

AbstractConventional 1D NMR methods and 2D shift‐correlated NMR experiments (COSY, HMQC, HMBC) were used for the structural elucidation and 1H and 13C chemical shifts assignments of four new types of chalcone dimers isolated from Myracrodruon urundeuva. Copyright © 2003 John Wiley & Sons, Ltd.

New Chalconoid Dimers fromMyracrodruon urundeuva

Abstract From the inner bark of a specimen of Myracrodruon urundeuva were isolated the new chalcone dimers 1 and 2, named urundeuvina A and B, as methyl ether derivatives (1a and 2a) obtained by methylation with diazomethane. The structure elucidation of these derivatives involved spectral data analysis, including 2D NMR experiments and NOE difference spectra.

Structure of the chalcone dimers lophirone F, and H from Lophira lanceolata stem bark

Abstract Structural elucidation of three chalcone dimers, (lophirones F, G and H) isolated from Lophira lanceolata stem bark, and their permethylethers, is discussed using spectral chemical evidence.

Structures of isombamichalcone and lophirochalcone, bi- and tetra-flavonoids from lophira lanceolata

From the stem bark of Lophira lanceolata two new flavonoids, a chalcone dimer, isombamichalcone 1, and a tetraflavonoid, lophirochalcone 4 have been isolated.