150433-18-4Relevant academic research and scientific papers
Sequential Cleavage of Lignin Systems by Nitrogen Monoxide and Hydrazine
Altmann, Lisa-Marie,Heinrich, Markus R.,Hofmann, Dagmar,Hofmann, Laura Elena,Prusko, Lea
supporting information, (2020/03/27)
The cleavage of representative lignin systems has been achieved in a metal-free two-step sequence first employing nitrogen monoxide for oxidation followed by hydrazine for reductive C?O bond scission. In combining nitrogen monoxide and lignin, the newly developed valorization strategy shows the particular feature of starting from two waste materials, and it further exploits the attractive conditions of a Wolff-Kishner reduction for C?O bond cleavage for the first time. (Figure presented.).
Design, synthesis and biological evaluation of novel vicinal diaryl-substituted 1H-Pyrazole analogues of combretastatin A-4 as highly potent tubulin polymerization inhibitors
Bortolozzi, Roberta,Brancale, Andrea,Camacho, Maria Encarnacion,Ferla, Salvatore,Grillo, Elisabetta,Hamel, Ernest,Mariotto, E.,Oliva, P.,Padroni, Chiara,Romagnoli, R.,Ronca, Roberto,Rruga, Fatlum,Salvador, Maria Kimatrai,Viola, Giampietro
, (2019/08/12)
A series of 3-(3′,4′,5′-trimethoxyphenyl)-4-substituted 1H-pyrazole and their related 3-aryl-4-(3′,4′,5′-trimethoxyphenyl)-1-H-pyrazole regioisomeric derivatives, prepared as cis-rigidified combretastatin A-4 (CA-4) analogues, were synthesized and evaluated for their in vitro antiproliferative against six different cancer cell lines and, for selected highly active compounds, inhibitory effects on tubulin polymerization, cell cycle effects and in vivo potency. We retained the 3′,4′,5′-trimethoxyphenyl moiety as ring A throughout the present investigation, and a structure-activity relationship (SAR) information was obtained by adding electron-withdrawing (OCF3, CF3) or electron-releasing (alkyl and alkoxy) groups on the second aryl ring, corresponding to the B-ring of CA-4, either at the 3- or 4-position of the pyrazole nucleus. In addition, the B-ring was replaced with a benzo[b]thien-2-yl moiety. For many of the compounds, their activity was greater than, or comparable with, that of CA-4. Maximal activity was observed with the two regioisomeric derivatives characterized by the presence of a 4-ethoxyphenyl and a 3′,4′,5′-trimethoxyphenyl group at the C-3 and C-4 positions, and vice versa, of the 1H-pyrazole ring. The data showed that the 3′,4′,5′-trimethoxyphenyl moiety can be moved from the 3- to the 4-position of the 1H-pyrazole ring without significantly affecting antiproliferative activity. The most active derivatives bound to the colchicine site of tubulin and inhibited tubulin polymerization at submicromolar concentrations. In vivo experiments, on an orthotopic murine mammary tumor, revealed that 4c inhibited tumor growth even at low concentrations (5 mg/kg) compared to CA-4P (30 mg/kg).
Consecutive three-component synthesis of 3-(hetero)aryl-1H-pyrazoles with propynal diethylacetal as a three-carbon building block
Levi, Lucilla,Boersch, Christina,Gers, Charlotte F.,Merkul, Eugen,Mueller, Thomas J. J.
, p. 9340 - 9356 (2012/01/04)
A novel consecutive three-component synthesis of 3-(hetero)aryl-1H- pyrazoles via room temperature Sonogashira arylation of propynal diethylacetal used as a propargyl aldehyde synthetic equivalent has been disclosed. The final acetal cleavage-cyclocondensation with hydrazine hydrochloride at 80 °C rapidly furnishes the title compounds in a one-pot fashion.
