62452-63-5Relevant articles and documents
Transition-Metal-Free One-Pot Synthesis of Naphthoquinonefuran Derivatives through Sequential Nucleophilic Substitution-Nucleophilic Addition Reaction
Li, Xiang,Sun, Peng,Xie, Kaijun,Zhou, Dun,Peng, Jinsong,Fan, Aihong,Zhang, Jing,Chen, Chunxia
, p. 9313 - 9320 (2020)
A transition-metal-free route for tandem one-pot synthesis of naphthoquinonefuran derivatives from 2-hydroxynaphthoquinones has been developed. The sequentially accomplished process comprises an intermolecular alkynylation of sp2-carbon at the 3 position of 2-hydroxynaphthoquinones with arylethynyl bromides, followed by a base-promoted intramolecular nucleophilic annulation reaction. A broad range of functional groups is compatible with this reaction, and diverse naphtho[2,3-b]furan-4,9-diones can be obtained with good yields and excellent regioselectivity.
New strategies for the synthesis of naphthoquinones employing Cu(II) complexes: Crystal structures and cytotoxicity
Azeredo, Nathália F.B.,Souza, Fabrícia P.,Demidoff, Felipe C.,Netto, Chaquip D.,Resende, Jackson A.L.C.,Franco, Roberto W.A.,Colepicolo, Pio,Ferreira, Ana M.C.,Fernandes, Christiane
, p. 11 - 20 (2017/09/26)
The syntheses, physico-chemical characterization and cytotoxicity toward three human cell lines (standard and resistant sarcoma cells, and fibroblast) of a new copper(II) complex [Cu(HBPA)(L1)Cl]·3H2O 2 are reported. Complex 2 was obtained through the reaction between the ligand stilbene-quinone (HL1) and Cu[HBPA]Cl2 1, where HBPA = 2-hydroxybenzyl-2pyridylmethylamine. The synthesis of HL1 was performed in high yield through Heck reaction on PEG-400. X-ray diffraction and solution studies (UV–Vis, EPR, ESI(+)?MS and ESI(+)?MS/MS) were performed for complex 2, in which the copper(II) center is coordinated to the quinone in its deprotonated form, to the ligand HBPA and to a chloro ligand. Similar reaction employing CuCl2·2H2O, instead of Cu[HBPA]Cl2 1 and HL1, has resulted in the obtainment of a furano-o-naphtoquinone (L2) with 99% selectivity, suggesting a new methodology to cyclize the ligand HL1. In order to obtain the analogous para-isomer (L3), and to evaluate the isomerism influence on cytotoxicity activity, a cyclization reaction of HL1 with NBS (N-bromosuccinimide) was also performed, which resulted in the obtainment of L2 (8%) and L3 (13%). X-ray diffraction studies were performed for L2 and complex 2, and the description of their structure elucidated. Results from MTT assay revealed that complex 2 is more active against sarcoma cell lines (MES-SA/Dx5 and MES-SA) than both the free ligand HL1 and complex 1, reducing cell viability to less than 50 μmol L?1. L2 was the most active in the series, presenting cytotoxicity against resistant MES-SA/Dx5 and its standard MES-SA cell line, respectively, three and ten times higher than the current drug doxorubicin.
Synthesis of Stilbene-Quinone Hybrids through Heck Reactions in PEG-400
Demidoff, Felipe C.,De Souza, Fabrícia P.,Netto, Chaquip D.
supporting information, p. 5217 - 5223 (2017/11/28)
Styrenes were coupled with 3-iodolawsone in PEG-400 at 90 °C, leading stereoselectively to (E)-stilbene-quinone hybrids through Heck reactions. The best reaction conditions were found to be the use of NaOH (3 equiv) and 10 mol% of palladium acetate at 90 °C for 15 minutes. The chemical yields of the Heck reactions using styrenes with electron-withdrawing groups (65-98%) were greater than styrenes bearing electron-donating groups (7-32%) on the aromatic ring. In particular, the chemical yields of Heck reactions involving nitrostyrenes were the best ones observed.
