Synthesis and Antioxidative Activity of 3′,4′,6,7-Tetrahydroxyaurone, a Metabolite ofBidens frondosa

Chemical composition and insecticidal properties of the essential oil of <i>Bidens frondosa</i> L (Asteraceae) against booklice (<i>Liposcelis bostrychophila</i>)

“…The aerial parts of B. frondosa have been used to treat virtual fatigue, night sweat; hemoptysis, infantile malnutrition and dysentery in traditional Chinese medicine [6] and young leaves of B. frondosa are utilized as human food and tea [3]. It seems that the aerial parts of B. frondosa are quite safe for human consumption.…”

“…Chinese traditional medicine made use of the aerial parts of B. frondosa to treat virtual fatigue, night sweat hemoptysis, infantile malnutritioal and dysentery [4]. Various polyacetylenes, acylated glucosides, flavonoids, phenylpropanoids, terpenoids, and sterols were isolated from this plant in the previous phytochemical investigations [5,6]. The composition of the essential oil derived from the leaves of B. frondosa has also been determined previously [3].…”

"On water" synthesis of aurones: first synthesis of 4,5,3',4',5'-pentamethoxy-6-hydroxyaurone from Smilax riparia

“…6 In another method acetic anhydride is used as condensation agent, but in this method the hydroxy groups will be acylated, and to get the desired product an additional hydrolysis step is needed. 9 However, the present green method does not require either hydrolysis or protection/deprotection of hydroxy groups. Thus, the condensation of benzofuranones 1c and 1d with 3,4-dihydroxybenzaldehyde in water at reflux temperature for 10 h gave sulfuretin (5), maritimetin (6) in 81% and 80% yields respectively (scheme 3).…”

“…Aurones possess a wide spectrum of pharmacological activities 2 such as anti-tumor/anti-cancer, [3][4][5][6] anti-diabetic, 7 anti-inflammatory, 8 anti-oxidant, 9 anti-bacterial, 10 anti-Alzheimer's, 11 insect antifeedant, 12 and tyrosinase. 13 Various approaches have been reported for the synthesis of aurones: (i) oxidative cyclization of 2'-hydroxychalcones using Hg(OAc)2 14,15 or Thallium(III) nitrate; 16 (ii) cyclization of 2'-acetoxychalcones using tetrabutylammonium tribromide; 17 (iii) ring closing reaction of 2-(1-hydroxy-3-arylprop-2-ynyl)phenols catalyzed by AuCl2; 18 (iv) recently via dihaloacrylic acids 19 and Cu-catalyzed cyclization of (2-halogenphenyl)(3-phenyloxiran-2-yl)methanones; 20 (v) the more convenient and practical use involves the condensation of benzofuran-3(2H)-ones with aryl aldehydes using various acidic or basic catalysts 21 under different conditions, such as KOH or NaOH/CH3OH, 10 HCl/CH3COOH, 22 Al2O3/CH2Cl2, 23 KF-Al2O3/CH2Cl2/MW, 24 EDDA/CH3CN/Ultrasound, 25 acetic anhydride 26 and using deep eutectic solvent.…”

“…Due to our interest on aurones and isoaurones, 9,14,28 here we report a simple, green and environment friendly method for the synthesis of aurones from readily available benzofuranones and benzaldehydes.…”