109899-87-8Relevant articles and documents
Novel Bifunctionalization of Activated Methylene: Base-Promoted Trifluoromethylthiolation of β-Diketones with Trifluoromethanesulfinyl Chloride
Sun, Dong-Wei,Jiang, Min,Liu, Jin-Tao
, p. 10797 - 10802 (2019/07/03)
A novel bifunctionalization of activated methylene was achieved successfully through the base-promoted trifluoromethylthiolation of β-diketones or β-ketoesters with trifluoromethanesulfinyl chloride. A series of α-trifluoromethylthiolated α-chloro-β-diketones and α-chloro-β-ketoesters were obtained in moderate to good yields under mild conditions. When β-diketones containing a phenyl group with a hydroxyl or amino substituent at the ortho position were used as substrates, intramolecular trifluoromethylthiolation/cyclization reaction took place to give the corresponding cyclic products. Furthermore, the protocol could be extended to perfluoroalkylthiolation with the sodium perfluoroalkanesulfinate/POCl3 system. On the basis of experimental results, plausible mechanisms are proposed.
Facile synthesis of new substituted aryl and heteroarylflavones by thermal and microwave assisted Suzuki-Miyaura coupling reaction
Joshi, Vidya,Govind Hatim, Jaywant
, p. 1002 - 1010 (2012/10/18)
Microwave assisted Suzuki-Miyaura coupling of 4′-bromoflavone 5 with substituted aryl and heteroarylboronic acids 6a-m gives high yields of aryl and heteroarylflavones 7a-m. Couplings have been carried out by three methods i) conventional heating with Pd(OCOCH3)2 catalyst, in solvent DMF(N,N-dimethylformamide) and base, aqueous Na2CO3 (2N) for 6-12 hr, at 110°C, yield 30-70%, ii) conventional heating with Pd[(C6H5)3P]4 catalyst, in DMF and base, aq. Na2CO3 (2N) for 6-12 hr, at 110°C, yield 40-72% and iii) Microwave heating with Pd[(C6H5)3P] 4 catalyst, in solvent (DMF+H2O, 5:2) and base, aq. Na2CO3 (2N) for 2-9 min, yield 50-87%. The substrate 4′-bromoflavone 5 has been synthesized from o-hydroxyacetophenone 1 in 3 steps. Esterification of 1 with 4-bromobenzoyl chloride 2 with montmorillonite-KSF catalyst, DCE (1,2-dichloroethane) and Et3N (triethylamine) which gives 2-(4- bromobenzoyloxy)acetophenone 3. Baker-Venkataraman rearrangement of 3 with pyridine and KOH further gives 1-(4-bromophenyl)-3-(2- hydroxyphenyl)propane-1,3-dione 4, followed by cyclization of 4 with methanolic sulfuric acid (2.5%) which yields 4'-bromoflavone 5, yield 82%.
Benzoflavone activators of the cystic fibrosis transmembrane conductance regulator: Towards a pharmacophore model for the nucleotide-binding domain
Springsteel, Mark F.,Galietta, Luis J. V.,Ma, Tonghui,By, Kolbot,Berger, Gideon O.,Yang, Hong,Dicus, Christopher W.,Choung, Wonken,Quan, Chao,Shelat, Anang A.,Guy, R. Kiplin,Verkman,Kurth, Mark J.,Nantz, Michael H.
, p. 4113 - 4120 (2007/10/03)
Our previous screen of flavones and related heterocycles for the ability to activate the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel indicated that UCCF-029, a 7,8-benzoflavone, was a potent activator. In the present study, we describe the synthesis and evaluation, using cell-based assays, of a series of benzoflavone analogues to examine structure-activity relationships and to identify compounds having greater potency for activation of both wild type CFTR and a mutant CFTR (G551D-CFTR) that causes cystic fibrosis in some human subjects. Using UCCF-029 as a structural guide, a panel of 77 flavonoid analogues was prepared. Analysis of the panel in FRT cells indicated that benzannulation of the flavone A-ring at the 7,8-position greatly improved compound activity and potency for several flavonoids. Incorporation of a B-ring pyridyl nitrogen either at the 3- or 4-position also elevated CFTR activity, but the influence of this structural modification was not as uniform as the influence of benzannulation. The most potent new analogue, UCCF-339, activated wild-type CFTR with a Kd of 1.7 μM, which is more active than the previous most potent flavonoid activator of CFTR, apigenin. Several compounds in the benzoflavone panel also activated G551D-CFTR, but none were as active as apigenin. Pharmacophore modeling suggests a common binding mode for the flavones and other known CFTR activators at one of the nucleotide-binding sites, allowing for the rational development of more potent flavone analogues.
