Search results for "Stilbenoid"
showing 7 items of 17 documents
Star-shaped conjugated compounds forming nematic discotic systems
2004
Abstract Star-shaped compounds, having a benzene ( 9a,b ) or a 1,3,5-triazine ( 11a,b ) core and stilbenoid arms were prepared. Hexyloxy chains, attached in the middle of the arms, provide nematic discotic phases ND, which are unusual for such systems. The position of the sidechains prevents the micro-segregation, which is valid for star-shaped discs of columnar phases. The stilbenoid character of 9a,b and 11a,b guarantees a high light sensitivity. Apart from the statistical CC bond formation by irradiation in solution or in the LC phases, a topochemically controlled chemo-, regio- and stereoselective photocyclodimerization 11a → 12 was found in the crystalline state. The structure determin…
Major orchestration of shikimate, early phenylpropanoid and stilbenoid pathways by Subgroup 2 R2R3-MYBs in grapevine
2021
AbstractThe stilbenoid pathway is responsible for the production of resveratrol and its derivatives in grapevine. A few transcription factors (TFs) have been previously identified as regulators of this pathway but the extent of this control is yet to be fully understood. Here we demonstrate how DNA affinity purification sequencing (DAP-Seq) allows for genome-wide TF binding site interrogation in a non-model species. We obtained 5,190 and 4,443 binding events assigned to 4,041 and 3,626 genes for MYB14 and MYB15, respectively (around 40% of peaks being located within -10kb of transcription start sites). DAP-Seq of MYB14 and MYB15 was combined with aggregate gene centred co-expression network…
Bis-, Tris-, and Tetrakis(squaraines) Linked by Stilbenoid Scaffolds
2001
The oligosquaraines 1−5, with stilbenoid scaffolds, were prepared by multistep syntheses in which the final steps consisted of condensation reactions between the semisquaric acid 21 and multiple resorcinols 12b−15b and 17b. The target compounds exhibit intense (ϵ > 250000 L·mol−1·cm−1) and sharp absorption bands with maxima between 687 to 778 nm, depending on the conjugation in the stilbenoid scaffold. Comparison with the monosquaraine 6 as a model compound reveals intramolecular interactions between different donor−acceptor−donor moieties, which give rise to increased absorption intensities.
ChemInform Abstract: Bis-, Tris-, and Tetrakis(squaraines) Linked by Stilbenoid Scaffolds.
2010
The oligosquaraines 1−5, with stilbenoid scaffolds, were prepared by multistep syntheses in which the final steps consisted of condensation reactions between the semisquaric acid 21 and multiple resorcinols 12b−15b and 17b. The target compounds exhibit intense (ϵ > 250000 L·mol−1·cm−1) and sharp absorption bands with maxima between 687 to 778 nm, depending on the conjugation in the stilbenoid scaffold. Comparison with the monosquaraine 6 as a model compound reveals intramolecular interactions between different donor−acceptor−donor moieties, which give rise to increased absorption intensities.
Synthesis of Tetrastilbenylmethanes by Wittig−Horner Reactions
2004
The all-(E)-configured tetrastilbenylmethanes 3a−e and 5a,b can be obtained by fourfold Wittig−Horner reactions. The tetrahedral arrangement of these compounds guarantees independent stilbenoid chromophores with a high chromophore density. Apart from (E)/(Z) isomerization reactions, irradiation leads to a three-dimensional network with isolated unchanged stilbene units. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Classification of stilbenoid compounds by entropy of artificial intelligence
2013
A set of 66 stilbenoid compounds is classified into a system of periodic properties by using a procedure based on artificial intelligence, information entropy theory. Eight characteristics in hierarchical order are used to classify structurally the stilbenoids. The former five features mark the group or column while the latter three are used to indicate the row or period in the table of periodic classification. Those stilbenoids in the same group are suggested to present similar properties. Furthermore, compounds also in the same period will show maximum resemblance. In this report, the stilbenoids in the table are related to experimental data of bioactivity and antioxidant properties avail…
Antioxidant stilbenoid and flavanonol from stem ofErythrophleum suaveolens(Guill. & Perr.)
2015
Keywords: NMR; 1H NMR; Caesalpiniaceae; Erythrophleum suaveolens; flavanonol; stilbenoid; radical scavenging activity