182425-73-6Relevant academic research and scientific papers
Preparation of 3,4-Substituted-5-Aminopyrazoles and 4-Substituted-2-Aminothiazoles
Havel, Stepan,Khirsariya, Prashant,Akavaram, Naresh,Paruch, Kamil,Carbain, Benoit
, p. 15380 - 15405 (2019/01/04)
3,4-Substituted-5-aminopyrazoles and 4-substituted-2-aminothiazoles are frequently used intermediates in medicinal chemistry and drug discovery projects. We report an expedient flexible synthesis of 3,4-substituted-5-aminopyrazoles (35 examples), based on palladium-mediated α-arylation of β-ketonitriles with aryl bromides. A library of 4-substituted-2-aminothiazoles (21 examples) was assembled by a sequence employing Suzuki coupling of newly prepared, properly protected pinacol ester and MIDA ester of 4-boronic acid-2-aminothiazole with (hetero)aryl halides.
Pyrimethamine Derivatives: Insight into Binding Mechanism and Improved Enhancement of Mutant β- N -acetylhexosaminidase Activity
Tropak, Michael B.,Zhang, Jianmin,Yonekawa, Sayuri,Rigat, Brigitte A.,Aulakh, Virender S.,Smith, Matthew R.,Hwang, Hee-Jong,Ciufolini, Marco A.,Mahuran, Don J.
, p. 4483 - 4493 (2015/06/23)
In order to identify structural features of pyrimethamine (5-(4-chlorophenyl)-6-ethylpyrimidine-2,4-diamine) that contribute to its inhibitory activity (IC50 value) and chaperoning efficacy toward β-N-acetylhexosaminidase, derivatives of the compound were synthesized that differ at the positions bearing the amino, ethyl, and chloro groups. Whereas the amino groups proved to be critical to its inhibitory activity, a variety of substitutions at the chloro position only increased its IC50 by 2-3-fold. Replacing the ethyl group at the 6-position with butyl or methyl groups increased IC50 more than 10-fold. Surprisingly, despite its higher IC50, a derivative lacking the chlorine atom in the para-position was found to enhance enzyme activity in live patient cells a further 25% at concentrations >100 μM, while showing less toxicity. These findings demonstrate the importance of the phenyl group in modulating the chaperoning efficacy and toxicity profile of the derivatives.
Potential antimalarials. XXII Some 2,4-diamino-5-(3- and 4-trifluoromethylphenyl and 3,4-methylenedioxyphenyl)pyrimidines
Barlin, Gordon B.,Kotecka, Barbara,Rieckmann, Karl H.
, p. 647 - 650 (2007/10/03)
A series of 10 pyrimethamine analogues containing 3′- and 4′-trifluoromethyl and 3′,4′-methylenedioxy groups has been prepared and tested for in vitro antimalarial activity against the FC-27 and K-1 isolates of Plasmodium falciparum. Several of these compounds were almost as active as pyrimethamine against the drug-sensitive FC-27 isolate, and like pyrimethamine, they were much less active against the drug-resistant K-1 isolate. The 4′-trifluoromethyl compunds, however, showed much smaller differences.
