17823-94-8Relevant articles and documents
Orthogonal Cu- and Pd-based catalyst systems for the O- and N-arylation of aminophenols
Maiti, Debabrata,Buchwald, Stephen L.
supporting information; experimental part, p. 17423 - 17429 (2010/03/25)
O- or N-arylated aminophenol products constitute a common structural motif in various potentially useful therapeutic agents and/or drug candidates. We have developed a complementary set of Cu- and Pd-based catalyst systems for the selective O- and N-arylation of unprotected aminophenols using aryl halides. Selective O-arylation of 3- and 4-aminophenols is achieved with copper-catalyzed methods employing picolinic acid or CyDMEDA, trans-N,N′-dimethyl-1,2- cyclohexanediamine, respectively, as the ligand. The selective formation of N-arylated products of 3- and 4-aminophenols can be obtained with BrettPhos precatalyst, a biarylmonophosphine-based palladium catalyst. 2-Aminophenol can be selectively N-arylated with CuI, although no system for the selective O-arylation could be found. Coupling partners with diverse electronic properties and a variety of functional groups can be selectively transformed under these conditions.
Discovery of a simple picomolar inhibitor of cholesteryl ester transfer protein
Reinhard, Emily J.,Wang, Jane L.,Durley, Richard C.,Fobian, Yvette M.,Grapperhaus, Margaret L.,Hickory, Brian S.,Massa, Mark A.,Norton, Monica B.,Promo, Michele A.,Tollefson, Michael B.,Vernier, William F.,Connolly, Daniel T.,Witherbee, Bryan J.,Melton, Michele A.,Regina, Karen J.,Smith, Mark E.,Sikorski, James A.
, p. 2152 - 2168 (2007/10/03)
A novel series of substituted N-[3-(1,1,2,2-tetrafluoroethoxy)benzyl]-N-(3-phenoxyphenyl)-trifluoro-3- amino-2-propanols is described which potently and reversibly inhibit cholesteryl ester transfer protein (CETP). Starting from the initial lead 1, various substituents were introduced into the 3-phenoxyaniline group to optimize the relative activity for inhibition of the CETP-mediated transfer of [3H]-cholesteryl ester from HDL donor particles to LDL acceptor particles either in buffer or in human serum. The better inhibitors in the buffer assay clustered among compounds in which the phenoxy group was substituted at the 3, 4, or 5 positions. In general, small lipophilic alkyl, haloalkyl, haloalkoxy, and halogen moieties increased potency relative to 1, while analogues containing electron-donating or hydrogen bond accepting groups exhibited lower potency. Compounds with polar or strong electron-withdrawing groups also displayed lower potency. Replacement of the phenoxy ring in 1 with either simple aliphatic or cycloalkyl ethers as well as basic heteroaryloxy groups led to reduced potency. From the better compounds, a representative series 4a-i was prepared as the chirally pure R(+) enantiomers, and from these, the 4-chloro-3-ethylphenoxy analogue was identified as a potent inhibitor of CETP activity in buffer (4a, IC50 0.77 nM, 59 nM in human serum). The simple R(+) enantiomer 4a represents the most potent acyclic CETP inhibitor reported. The chiral synthesis and biochemical characterization of 4a are reported along with its preliminary pharmacological assessment in animals.
