A molecular modeling study was carried out to develop a predictive model for combretastatin-like analogues populating the colchicine-binding site of beta-tubulin. A series of compounds built around a framework including two aromatic groups linked by various moieties such as alkenes (stilbenes), enones (chalcones), or ethers was selected for the study. The 5D-QSAR model was developed stepwise. F...

Anthocyanins are colorful plant pigments with promising applications as pharmaceuticals and colorants. In order to engineer efficient pigment biosynthesis in Escherichia coli, the activities of various dihydroflavonol 4-reductases (DFRs) were characterized for the three primary dihydroflavonol substrates. The biochemical assays demonstrated variable DFR activities for dihydroflavonol with one B...

The distribution patterns of flavonoids and cyclohexenyl chalcone derivatives in conventional propagated (CP) and in vitro-derived (CPA) field-grown plants of an important medicinal ginger, Boesenbergia rotunda, are described. A total of eight compounds were extracted from six organs (rootlet, rhizome, shoot base, maroon stem, stalk, and leaf) of the CP and CPA plants. Five major chromatographi...

A genomic clone encoding flavanone 3-hydroxylase (F3H) was isolated from Arabidopsis thaliana. The deduced amino acid sequence is 72 to 94% identical to all previously reported F3H proteins. Low-stringency DNA blot analysis indicated that F3H is encoded by a single gene in Arabidopsis. The F3H locus was mapped to the bottom of chromosome 3 and therefore does not correspond to any of the 13 flav...

A genomic clone encoding flavanone 3-hydroxylase (F3H) was isolated from Arabidopsis thaliana. The deduced amino acid sequence is 72 to 94% identical to all previously reported F3H proteins. Low-stringency DNA blot analysis indicated that F3H is encoded by a single gene in Arabidopsis. The F3H locus was mapped to the bottom of chromosome 3 and therefore does not correspond to any of the 13 flav...

Chenopodiaceae, Spinacia oleracea, Flavonoid Metabolism, Chalcone Synthase, Two Different Activities Chalcone synthase activity was found in enzyme preparations from spinach. In homogenates o f young leaves two different activities o f the enzyme could be separated by DEAE-ion exchange chromatography and chromatofocusing. Both activities formed naringenin with [2-14C] malonylCoA and 4-coumaroyl...

To evaluate the effect of increased expression of genes involved in flower pigmentation, additional dihydroflavonol-4-reductase (DFR) or chalcone synthase (CHS) genes were transferred to petunia. In most transformants, the increased expression had no measurable effect on floral pigmentation. Surprisingly, however, in up to 25% of the transformants, a reduced floral pigmentation, accompanied by ...

Boesenbergia rotunda (L.) cyclohexenyl chalcone derivatives, 4-hydroxypanduratin A and panduratin A, showed good competitive inhibitory activities towards dengue 2 virus NS3 protease with the Ki values of 21 and 25 microM, respectively, whilst those of pinostrobin and cardamonin were observed to be non-competitive. NMR and GCMS spectroscopic data formed the basis of assignment of structures of ...

Chalcone/flavanone interconversion occurs facilely under aqueous alkaline conditions making it a promising scaffold for the development of a covalent molecular switch. In this study, a single methoxy substituent is shown to have a significant impact on the equilibrium dynamics of this reaction; this impact is dependent on the site of substitution.

In the title chalcone derivative, C(15)H(9)Cl(3)O, the dihedral angle between the 2-chloro-phenyl and 2,4-dichloro-phenyl rings is 41.79 (14)°. Weak C-H⋯O and C-H⋯Cl intra-molecular inter-actions involving the enone unit generate S(5) ring motifs. In the crystal structure, the mol-ecules are arranged in a head-to-tail manner along the a axis. These chains are stacked along the b axis.