Structure-Activity Relationships of Flavonoids,Isolated fromScutellaria baicalensis,Binding to Benzodiazepine Site of GABA_AReceptor Complex

Abstract

Twenty-six flavonoids were isolated from Scutellaria baicalensis. Their affinities for the benzodiazepine (BDZ) binding site of GABA A receptor have been studied using [ 3H]flunitrazepam binding to rat cortical membranes in vitro. The structure-activity relationships suggested that 2'-OH flavones exhibited the most potent binding affinity, which could lead to the design and discovery of new BDZ receptor ligands.

Rhus parviflora and its biflavonoid constituent, rhusflavone, induce sleep through the positive allosteric modulation of GABAA-benzodiazepine receptors

“…3). The presence of conjugated ketones as stated by Wang et al, (2002), and a C6-C8 00 biflavonoid linkage may have a significant role in enhanced affinities for the BZD-site.…”

Skullcap Scutellaria lateriflora L.: An American nervine

“…Flavone-glucuronides (e.g. baicalin, wogonin-7-Oglucuronide) had a low affinity for the benzodiazepine binding site (Wang et al, 2002a). The binding affinity of flavones was much higher, especially for flavones with a 2 -hydroxyl group.…”

“…The binding affinity of flavones was much higher, especially for flavones with a 2 -hydroxyl group. Of the flavones known to occur in S. lateriflora, oroxylin A showed the highest affinity to the receptor, followed by wogonin, while baicalein was not very active (Huen et al, 2003a;Wang et al, 2002a). Hui et al (2002) investigated the anxiolytic activities of wogonin in mice and found a similar response between wogonin (7.5-30 mg/kg oral) and diazepam (1 mg/kg) in the elevated plus-maze test.…”

Synergistic Antitumor Effect of Genitinib (Iressa®) with Flavonoids from the Scutellaria baicalensis Root on the Non-Small Cell Lung Cells

“…MS-275 was synthesized according to the reported procedure [12]. The Wogon flavonoids were previously isolated in Prof. Taniguchi's laboratory [13,14].…”