Synthesis and in vitro antiplasmodial evaluation of 4-anilino-2-trichloromethylquinazolines
摘要:
To identify a new safe antiplasmodial molecular scaffold, an original series of 2-trichloromethylquinazolines, functionalized in position 4 by an alkyl-or arylamino substituent, was synthesized from 4-chloro-2-trichloromethylquinazoline 1, via a cheap, fast and efficient solvent-free operating procedure. Among the 40 molecules prepared, several exhibit a good profile with both a significant antiplasmodial activity on the W2 Plasmodium falciparum strain (IC50 values: 0.4-2.2 mu M) and a promising toxicological behavior regarding human cells (HepG2/W2 selectivity indexes: 40-83), compared to the antimalarial drug compounds chloroquine and doxycycline. The in vitro antitoxoplasmic and antileishmanial evaluations were conducted in parallel on the most active molecules, showing that these ones specifically display antiplasmodial properties. (C) 2009 Elsevier Ltd. All rights reserved.
A new DMAP-catalyzed and microwave-assisted approach for introducing heteroarylamino substituents at position-4 of the quinazoline ring
摘要:
We report herein a new methodology for synthesizing quinazoline derivatives bearing a heteroarylamino moiety at position-4 of the quinazoline ring. As an alternative to the Buchwald-Hartwig cross-coupling reaction, which appears, until now, as the only efficient way to react 4-chloroquinazolines with numerous amino nitrogen-containing heterocycles displaying poor nucleophilicity, we developed a DMAP-catalyzed reaction involving microwave irradiation. Optimization of the reaction conditions led to the use of 30 mol % of DMAP in toluene, using a monomode microwave reactor and sealed vials. Moreover, the SNAr reaction intermediate salt was isolated and fully characterized. Finally, the procedure was extended to two different 2-substituted-quinazoline series and also to various anilines, demonstrating that this approach was a general efficient way to access to such 4-substituted quinazoline scaffolds of high pharmaceutical interest. (C) 2014 Elsevier Ltd. All rights reserved.