Four new isoflavanones from Tadehagi triquetrum

Four new isoflavanones with isoprenoid units,named triquetrumones E-H(1-4),were isolated from the whole plants of Tadehagi triquetrum.The structures were elucidated on the basis of spectroscopic analyses,including application of MS,UV,IR,1D and 2D NMR spectroscopic techniques.

A practical synthesis of a new series of isoflavanones

A practical six-step synthesis of 12 methylated and hydroxylated isoflavanones was accomplished starting from readily available m-xylene. A significant improvement of this procedure included application of the simple and commercially available reagents, avoidance of expensive reagents and catalysts, simple operations and excellent yields.

New flavonoids from bioactive extract of Algerian medicinal plant Launeae arborescens

Objective:To investigate the butanol fraction of the water/acetone extract and isolate of the new flavonoids from Launeae arboescens.Methods:The compounds were isolated by liquid chromatographic methods and their structures were identified by using spectroscopic analysis.Results:The isolated compounds were identified as:7-0-[α-rhamnopyranosyl 4',5,6-Trihydroxy flavone 1,4',5'-Di-Methoxy 7-(5"-Me Hexan)1-oyl flavanone 2,3"-isopropyl pyrano[1":7,4":6]3',4',5',5-Tetrahydroxy flavanone 3,5,4',5'-Tri-Hydroxy 7-(3"-Me butan)-yl flavanone 4.5,7-Dihydroxy-2',4',5'-trimethoxy-isoflavanone 5,5,6,7,4'-tetrahydroxy flavonol 6,7-O-[α-rhamnopyranosyl-(1->6)-β-glucopyranosyl]-4',5,7-tri-hydroxy-flavanone 7,7-O-[α-rhamnopyranosyl-(1->6)-β-glucopyranosyl]3',5-Dihydroxy 4'-Methoxy flavanone 8.Conclusions:The presence of different types of bioactive flavonoids in Launeae arhoescens extract can explain the large ethnopharmacological uses and the potential activity of this medicinal plant.

Geranylated or prenylated flavonoids from Cajanus volubilis

Five new flavonoid derivatives,cajavolubones A-E(1-5),along with six known analogues(6-11)were isolated from Cajanus volubilis,and their structures were elucidated by spectroscopic analysis and quantum chemical calculations.Cajavolubones A and B(1 and 2)were identified as two geranylated chalcones.Cajavolubone C(3)was a prenylated flavone,while cajavolubones D and E(4 and 5)were two prenylated isoflavanones.Compounds 3,8,9 and 11 displayed cytotoxicity against HCT-116 cancer cell line.

Syntheses and Br…π supramolecular interactions in the crystal structure of ipriflavone bromides

Two novel compounds,3,8-dibromo-2-methoxyl-7-isopropoxyisoflavanone (1) and 3,6-dibromo-2-methoxyl-7-isopropoxyisoflavanone (2),are synthesized via bromination reaction of their precursor ipriflavone in methanol.The mixture of 1 and 2 co-crystallizes in ethanol and forms two different crystal shapes,the shape of 1 being block and 2 prism,they can be separated manually.1 and 2 are characterized by IR,1H NMR and single crystal X-ray diffraction.The mechanism of bromination reaction is also discussed.1 crystallizes in the monoclinic space group P 21/n with cell parameters a = 1.3569(3) nm,b = 0.6706(2) nm,c = 2.0704(4) nm,?= 97.50(2)°,V = 1.8678(6) nm3,Z = 4,Dc = 1.672 Mg/m3,R = 0.0455,wR = 0.0779,F(000) = 936.2 crystallizes in the monoclinic space group P 21/c with cell parameters a =1.3854(17) nm,b = 1.1215(14) nm,c = 1.3038(17) nm,? = 103.71(2)°,V = 1.968(4) nm3,Z = 4,Dc = 1.587 Mg/m3,R = 0.0306,wR = 0.0619,F(000) = 936.The Br…p interactions,hydrogen bonds,aromatic hy-drogen bonds and aromatic stacking interactions exist in the crystal structures of 1 and 2,which lead them into supramolecular compounds with a three-dimensional network structure,respec-tively.1 and 2 are the isoflavanone derivatives halogenated at C3 and this kind of isoflavanone halides has not been reported yet.