A novel HAuCl4@UiO-66-NH2 material has been obtained and utilized as a heterogeneous Au(III) catalyst. This Au(III) catalyst was able to promote the formation of a variety of dihydrochalcones starting from 2H-chromenes in moderate to good yields. A tandem hydride shift/hydration reaction sequence has been proposed based on deuterium labeling studies, which revealed a 1,5-hydride shift reaction ...

Two new dihydrochalcones, 2',4'-dihydroxy-3'-methoxydihydrochalcone, (-)-3'-methoxy-2',4',beta-trihydroxydihydrochalcone, a new flavanone, (2 S)-(-)-5'-hydroxy-7,3',4'-trimethoxyflavanone, and a new flavonol derivative, muntingone, along with sixteen known compounds, were isolated from the leaves of Muntingia calabura. The structures of these new compounds were determined using spectral analyse...

A fractionation method was used to extract phenolic compounds from apple pomace (AP) involving a first extraction with water and subsequent extractions of the same residue with two different organic solvents. The water extracts obtained contained high amounts of phenolic compounds with high antioxidant capacity. However, the second and third extractions of the same residue still extracted consi...

A group of flavones, isoflavones, flavanones, and chalcones was subjected to small-scale biotransformation studies with the Gram-negative Stenotrophomonas maltophilia KB2 strain in order to evaluate the capability of this strain to transform flavonoid compounds and to investigate the relationship between compound structure and transformation type. The tested strain transformed flavanones and ch...

Lucidene (l), a bis(benzopyrany1) sesquiterpene was isolated from the rootbark of Uvaria lucida ssp. lucida, and ita structure was determined by spectroscopic methods and single-crystal X-ray crystallography. It is optically inactive and crystallizes in enantiomeric pairs. High-resolution 'H NMR (400 and 600 MHz) spectroscopy allowed the assignment of all protons and indicated the existence of ...

Farinose exudates on fronds of Notholaena species are known to consist of flavonoid aglycones. These are predominantly methylated flavones and flavonols, sometimes chalcones and dihydrochalcones. Flavonols with unusual properties, excreted as major farina components by some species, have been found to be derivatives of methylated flavonols, esterified in position 8 with butyric or acetic acids,...