76288-41-0Relevant academic research and scientific papers
TWO DIBENZOYLMETHANES FROM THE FROND EXUDATE OF NOTHOLAENA SPECIES
Roitman, James N.,Mann, Karin,Wollenweber, Eckhard
, p. 985 - 988 (1992)
Fronds of various ferns in the genus notholaena produce an exudate which consists mostly of flavonoid aglycones.In some species we found small amounts of two dibenzoylmethanes or β-diketones.These have been identified by spectroscopic methods.Both, 2',β,4-trihydroxy-4',6'-dimethoxychalcone and 2',β-dihydroxy-4',6',4-trimethoxychalcone, are novel natural products.The structures have been confirmed by synthesis of the latter compound. Key words: Notholaena; Pteridaceae; frond exudates; β-diketones; 2',β,4-trihydroxy-4',6'-dimethoxychalcone; 2',β-dihydroxy-4',6',4-trimethoxychalcone; 2',4'-dihydroxy-4',6'-dimethoxydibenzoylmethane, 2'-hydroxy-4',6',4-trimethoxydebenzoylmethane.
Transition-Metal-Free Photoinduced Intramolecular Annulation of 2,3-Di(hetero)arylchromen-4-one
Han, Jie,Wang, Tao,Liang, Yong,Li, Ying,Li, Chenchen,Wang, Rui,Feng, Siqi,Zhang, Zunting
supporting information, p. 3552 - 3555 (2017/07/17)
An efficient transition-metal-free photoinduced intracyclization of 4H-chromen-4-ones in EtOH-H2O (7:1, v/v) at ambient temperature for the construction of complicated fused-ring heteroaromatics is established. The reaction proceeds smoothly without requiring any catalysts/additives.
Synthesis and preliminary biological evaluation of chrysin derivatives as potential anticancer drugs
Zheng, Xing,Zhao, Fei Fei,Liu, Yun Mei,Yao, Xu,Zheng, Zi Tong,Luo, Xing,Liao, Duan Fang
scheme or table, p. 6 - 8 (2011/10/31)
A series of chrysin derivatives were prepared from 2-hydroxyacetophenone, 2,4-dihydroxyacetophenone, 2,4,6-trihydroxy- acetophenone, using modified Baker-Venkataraman transformation. Their anticancer activities in vitro were evaluated by the standard MTT method. The results of biological test showed that some of chrysin derivatives showed stronger anticancer activity than 5-fluorouracil.
COMPOSITIONS AND METHODS FOR POTENTIATING ANTIBIOTIC ACTIVITY
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, (2008/06/13)
[205] The present invention provides compounds that potentiate the activity of antibiotic agents, particularly quinolones such as norflaxin. The invention further provides compositions, e.g., pharmaceutical compositions, comprising the inventive compounds. The invention also provides compositions comprising an antibiotic (e.g., a quinolone) and a compound that potentiates activity of the antibiotic. The invention further provides methods of treating a subject comprising administering any of the inventive compounds or compositions to the subject. The invention also provides screening methods to identify compounds that potentiate the activity of an antibiotic, e.g., a quinolone.
Total synthesis of robustaflavone, a potential anti-hepatitis B agent
Zembower, David E.,Zhang, Heping
, p. 9300 - 9305 (2007/10/03)
Robustaflavone, a naturally occurring compound, is an inhibitor of hepatitis B virus replication in vitro. Robustaflavone is a biflavanoid composed of two units of apigenin (5,7,4'-trihydroxyflavone) joined via a biaryl linkage between the 6-position of one unit and the 3'-position of the other (I6,II3'-biapigenin). The natural material was isolated from the seed- kernels of Rhus succedanea. To provide ready access to sufficient quantities of material for continued biological studies, as well as to provide a general route for the preparation of structural analogues, a total synthesis of robustaflavone was pursued. The total synthesis was approached by constructing apigenin ethers containing functionalities at the 6- and 3'- positions which could be cross-coupled using transition metal catalysis. Key steps of the synthesis included development of a regioselective iodination of an apigenin derivative at the 6-position. Also key was the formation of an apigenin 3'-boronate using a palladium-catalyzed exchange of the corresponding 3'-iodide with a diboron reagent. Finally, identification of appropriate reaction conditions for Suzuki coupling to form the sterically congested 6-3''' biaryl bond of robustaflavone provided access to the desired biflavanoid system. This work represents the first total synthesis of robustaflavone.
New synthesis of 1,3-diarylpropane-1,3-diones
Bansal,Singh,Khanna
, p. 586 - 587 (2007/10/03)
1,3-Diarylpropane-1,3-diones have been synthesized by (i) UV irradiation and thermal rearrangement of o-aroyloxyacetophenones and (ii) microwave irradiation of aroyl chlorides and o-hydroyacetophenones.
Prenylation of Apigenin
Roy, D,Khanna, R. N.
, p. 583 - 586 (2007/10/02)
Apigenin (I) on prenylation with 2-methylbut-3-ene-2-ol affords two major and four minor products.The major products are characterized as 6-C-prenylapigenin (II) and 5,4'-dihydroxy-6'',6''-dimethyl-4'',5''-dihydropyranoflavone (III) and the minor products as 7-O-prenylapigenin (IV), 5,4'-dihydroxy-6'',6''-dimethyl-5''-C-prenyl-4'',5''-dihydropyranoflavone (V), 5,4'-dihydroxy-6'',6''-dimethyl-4'',5''-dihydropyranoflavone (VI) and 5,4'-dihydroxy-6'',6''-dimethyl-5''-C-prenyl-4'',5''-dihydropyranoflavone (VII).Prenylation of apigenin with prenyl bromide in presence of methanolic sodium methoxide yields two major products, identified as 6,8-di(C-prenyl)apigenin (VIII) and 6-C-prenylapigenin (II), and four minor products, viz. 7,4'-di-O-prenylapigenin (IX), 8-C-prenyl-5,4'-dihydroxy-6'',6''-dimethyl-4'',5''-dihydropyranoflavone (X), 7-O-prenylapigenin (IV) and 5,4'-dihydroxy-6'',6''-dimethyl-4'',5''-dihydropyranoflavone (VI).Apigenin has been synthesized by a new route in a better yield.
