93876-67-6Relevant academic research and scientific papers
Synthesis of Flavonols via Pyrrolidine Catalysis: Origins of the Selectivity for Flavonol versus Aurone
Xiong, Wei,Wang, Xiaohong,Shen, Xianyan,Hu, Cuifang,Wang, Xin,Wang, Fei,Zhang, Guolin,Wang, Chun
supporting information, p. 13160 - 13176 (2020/11/23)
A novel synthetic method for flavonol from 2′-hydroxyl acetophenone and benzaldehyde promoted by pyrrolidine under an aerobic condition in water is established. This protocol was supported by efficient synthesis of 44 common examples and three natural products. The α, β-unsaturated iminium ion (enimine ion E) was proved to be the key intermediate in the reaction. H218O and 18O2 isotope tracking experiments demonstrated that both water and the aerobic atmosphere were necessary to ensure the transformation. The selectivity for flavonol or aurone was originated from solvent-triggered intermediates, which were determined by UV-visible spectra from isolated enimine. The phenol-iminium E-A is dominant in water and the ketoenamine intermediate E-B is prevalent in acetonitrile. In the presence of pyrrolidine and oxygen, E-A leads to flavonol through E-I, a zwitterionic-like phenoloxyl-iminium ion, following the key steps of cyclization and a [2 + 2] oxidation; E-B proceeds through path II, a radical process induced by photolysis of E-B with both pyrrolidine and oxygen, to afford aurone. Preliminary mechanistic studies are reported.
Quercetin analogs with high fetal hemoglobin-inducing activity
Pabuprapap, Wachirachai,Wassanatip, Yanisa,Khetkam, Pichit,Chaichompoo, Waraluck,Kunkaewom, Sukanya,Senabud, Pongpan,Hata, Janejira,Chokchaisiri, Ratchanaporn,Svasti, Saovaros,Suksamrarn, Apichart
, p. 1755 - 1765 (2019/08/02)
β-Thalassemia is the major health problems in developing countries, when affected patients and healthy carriers are numerous, resulting a total absence or severe decrease in the production of β-globin chains. The use of chemical agents for increasing the production of fetal hemoglobin (HbF) by reactivating γ-globin gene to balance excess α-globin chains is an alternative therapeutic approach. Therefore, the search for molecules exhibiting the property of inducing γ-globin gene expression is of great interest. In this report, we discovered that quercetin (1), the major flavonoid isolated from the heartwoods of the medicinal plant Anaxagorea luzonensis promoted the expression of γ-globin gene. Chemical modification of 1 to fourteen methyl ether analogs (2?15) was conducted. The structures of these compounds were established on the basis of their spectroscopic data and by comparison with those of the reported values. The parent flavonoid and its chemically modified analogs were investigated for their γ-globin gene induction for the first time. The parent compound 1 exhibited less induced γ-globin gene expression than cisplatin and hemin, the positive controls. 3,4′-Di-O-methylquercetin (7), the modified analog, significantly enhanced γ-globin gene expression with 2.6-fold change at 8 μM, which was slightly higher than cisplatin and hemin. Moreover, compounds 1 and 7 displayed less cytotoxic activity against K562::ΔGγAγEGFP cells than cisplatin. Structure-activity relationship (SAR) study revealed that the methoxyl groups at the 3- and 4?-positions and the free hydroxyl group at the 7-position are required for strong HbF-inducing activity.
A 3 - hydroxy flavone and its derivatives of aqueous phase one-pot synthesis method (by machine translation)
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Paragraph 0060-0063; 0072-0076, (2019/02/25)
The invention belongs to the field of chemical synthesis, in particular to a 3 - hydroxy flavone and its derivatives of the one-pot synthesis method of the aqueous phase. The invention relates to 2 - hydroxy acetophenone and its derivatives with the benzaldehyde and its derivatives as the substrate of reaction, or 2 - hydroxy chalcone and its derivatives as the substrate of reaction, water or ethanol aqueous solution as the solvent, under the aerobic condition, 20 - 100 °C, reaction to obtain 3 - hydroxy flavone and its derivatives. The present invention provides a new reaction mechanism, has developed an efficient, convenient, wide adaptability of the substrate 3 - hydroxy flavone synthesis method; the invention also the use of the new method to synthesize a brand-new 3 - hydroxy flavone derivatives, in the health care field has important application value. (by machine translation)
