Synthesis of fused pyran and arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane in ionic liquid

Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis（4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl）methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis（pyranon-3-yl）methane hybrids with potential biological activities were constructed.

The new antioxidant 1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2- dihydroquinoline has a protective effect against carbon tetrachloride-induced hepatic injury in rats

Liver diseases with the central pathogenetic mechanism of oxidative stress are one of the main causes of mortality worldwide.Therefore,dihydroquinoline derivatives,which are precursors of hepatoprotectors and have antioxidant activity,are of interest.We have previously found that some compounds in this class have the ability to normalize redox homeostasis under experimental conditions.Here,we initially analyzed the hepatoprotective potential of the dihydroquinoline derivative 1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline(BHDQ)for carbon tetrachloride(CCl4)-induced liver injury in rats.Results suggested that BHDQ normalized the alanine aminotransferase,aspartate aminotransferase,and gamma-glutamyl transpeptidase in serum.We also observed an improvement in liver tissue morphology related to BHDQ.Animals with CCl4-induced liver injuries treated with BHDQ had less oxidative stress compared to animals with CCl4-induced liver injury.BHDQ promoted activation changes in superoxide dismutase,catalase,glutathione peroxidase,glutathione reductase,and glutathione transferase on control values in animals with CCl4-induced liver injury.BHDQ also activated gene transcription in Sod1 and Gpx1 via nuclear factor erythroid 2-related factor 2 and forkhead box protein O1 factors.Therefore,the compound of concern has a hepatoprotective effect by inhibiting the development of necrotic processes in the liver tissue,through antioxidation.

Argentum 5-Hydroxy-7-methoxy-2-phenyl-4H-chromen-4-one-6-sulfonate:Synthesis,Crystal Structure and Antitumor Activity

In order to improve the water solubility and bioavailability of 5-hydroxy-7-methoxyflavone,argentum 5-hydroxy-7-methoxy-2-phenyl-4H-chromen-4-one-6-sulfonate[Ag4(H2O)6](C(16)H(11)O4SO3)4·H2O(1,C(16)H(11)O4SO3=5-hydroxy-7-methoxy-2-phenyl-4H-chromen-4-one-6-sulfonate)was synthesized by sulfonation reaction.The structure of 1 was characterized by FT-IR,elemental analysis and X-ray single-crystal diffraction.Complex 1 belongs to the triclinic system,space group P1,a=8.077(4),b=12.365(4),c=17.735(7)A,V=1685.0(12)A3,Z=1,μ=1.372 mm^–1,Dc=1.936 g/cm^3,F(000)=984,the final R=0.0819 and wR=0.2332 with I>2σ(I).3D structure of 1 exhibits alternating organic and inorganic regions.O–H×××O hydrogen bonds and Ag–O coordination interactions exist among crystal water,coordinated water and sulfo group,which constructed an organic zone.Flavone skeletons form organic region of 1.Sulfo group is the bridge linking these two regions.The in vitro antitumor activity of 1 against human lymphoma cells U937 and human breast cancer cells MCF-7 were evaluated with CCK-8 assay.The result shows that 1 showed inhibitory activity against tumour cell U937 and MCF-7,and indicated that flavone sulfonate derivatives may be potential leads for further biological screenings and may generate drug-like molecules.

A new phenolic compound from Crinum asiaticum L.

A new phenolic compound was isolated from the ethanol extract of the bulbs of Crinum asiaticum L.var.sinicum Baker.Its structure was defined as 1-（2-hydroxy-4-hydroxymethyl）phenyl-6-O-caffeoyl-β-D-gluco-pyranoside on the basis of spectroscopic evidences.

A New Halogenated Biindole and A New Apo-carotenone from Green Alga Chaetomorpha basiretorsa Setchell

A new halogenated biindole and a new apo-carotenone have been isolated from the ethanolic extract of the green alga Chaetomorpha basiretorsa Sethcell. On the basis of chemical and spectroscopic methods including 2D NMR technique, their structures have been elucidated as 4,4′-dichloro-5,5′-dibromo-7,7′-dimethoxy-2,2′-bi-1H-indole and 1′S*,4′R*-8-(4′-hydroxy-2′,6′,6′- trimethylcyclohex-2-enyl)-6-methyloct-3E,5E,7E-trien-2-one, respectively.

A New Chromone Derivative from Stellera chamaejasme L

A new chromone derivative, 3-[1- (2, 4, 6-trihydroxyphenyl) 3-di-(4-hydroxyphenyl) 1-propanone-2-yl] 5,7-dihydroxy-8-di(4-hydroxyphenyl)methyl-4H-1-benzopyran-4-one, named as isomohsenone was isolated from the roots of Stellera chamaejasme L. together with known chamaechromone. Its structure was determined by the analysis of MS and NMR data, especially 2D NMR spectra.

A New Bisxanthone from Hypericum japonicum Thunb.ex Murray

A new bisxanthone, named bijaponicaxanthone C, was isolated from the whole plant of Hypericum japonicum. The structure was elucidated as 6-[1’’,5’’,6’’-trihydroxy-2’’’-(β-hydroxy-β- methylethyl)-2’’’,3’’’-dihydrofuran(5’’’,4’’’,3’’,4’’)xanthone-3’’’-oxyl]-1,3,5-trihydroxy-4-isoprenylxant- hone (1) on the basis of the spectral and chemical evidences.

New flavan and unusual chalcone glycosides from Drypetes parvifolia

Two new compounds 7-hydroxy-5-O-（β-D-glucopyranoside） flavan （1） and （Z）-4＇,6＇-dihydroxy-2＇-O-（β-D-glucopyranoside） chalcone （2）, along with eight known compounds, were isolated from the stem bark of Drypetes parvifolia （Euphorbiaceae）. Their structures were established on the basis of spectroscopic analysis and chemical evidence.

A Phenolic Glucoside from Alangium plantanifolium

A novel phenolic glucoside was isolated from stem barks of Alangium plantanifolium, its structure was elucidated to be 1-O-[2-(1-hydroxy-6-oxocyclohex-2-ene-1-carboxymethyl) -phenyl]-4, 6-O-[(S)-4, 4', 5, 5', 6, 6'-hexahydroxydi-phenoyl]-beta -D-glucopyranose 1 by spectroscopic methods including 2D NMR techniques.

4-(Succinimido)-1-butane sulfonic acid as a Bronsted acid catalyst for synthesis of pyrano[4,3-b]pyran derivatives under solvent-free conditions

4-（Succinimido）-1-butane sulfonic acid as an efficient and reusable Bronsted acid catalyzed the synthesis of pyrano[4,3-b]pyran derivatives under solvent-free conditions.The catalyst can be prepared by mixing succinimide and 1,4-butanesultone that is more simple and safer than the preparation of succinimide sulfonic acid.This method has the advantages of high yield,clean reaction,simple methodology and short reaction time.The catalyst could be recycled without significant loss of activity.