192049-20-0Relevant academic research and scientific papers
Urea anions: Simple, fast, and selective catalysts for ring-opening polymerizations
Lin, Binhong,Waymouth, Robert M.
, p. 1645 - 1652 (2017)
Aliphatic polyesters and polycarbonates are a class of biorenewable, biocompatible, and biodegradable materials. One of the most powerful methods for accessing these materials is the ring-opening polymerization (ROP) of cyclic monomers. Here we report that the deprotonation of ureas generates a class of versatile catalysts that are simultaneously fast and selective for the living ring-opening polymerization of several common monomers, including lactide, δ-valerolactone, ε-caprolactone, a cyclic carbonate, and a cyclic phosphoester. Spanning several orders of magnitude, the reactivities of several diaryl urea anions correlated to the electron-withdrawing substituents on the aryl rings. With the appropriate urea anions, the polymerizations reached high conversions (～90%) at room temperature within seconds (1-12 s), yielding polymers with narrow molecular weight distributions (Crossed D sign = 1.06 to 1.14). These versatile catalysts are simple to prepare, easy to use, and exhibit a range of activities that can be tuned for the optimal performance of a broad range of monomers. (Chemical Equation Presented).
Bronsted base/Lewis acid cooperative catalysis in the enantioselective Conia-ene reaction
Yang, Ting,Ferrali, Alessandro,Sladojevich, Filippo,Campbell, Leonie,Dixon, Darren J.
supporting information; experimental part, p. 9140 - 9141 (2009/12/06)
(Chemical Equation Presented) A mutually compatible and cooperative combination of copper(I) triflate and bifunctional 9-amino-9-deoxyepicinchona- derived urea compounds for the enantioselective Conia-ene cyclization of alkyne-tethered β-ketoester substrates is reported. The reaction is efficient, broad in scope, and easy to perform and allows access to chiral methylenecyclopentane products with high enantiocontrol. The transformation illustrates the concept of combining inactive precatalysts with inactive transition-metal-ion complexes in situ to reversibly create a catalytically active combination of the two.
Phosphate transport inhibitors
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, (2008/06/13)
Disclosed are compounds which have been identified as inhibitors of phosphate transport. Many of the compounds are represented by Structural Formula (I): Ar1—W—X—Y—Ar2; or a pharmaceutically acceptable salt thereof. Ar1 and Ar2 are independently a substituted or unsubstituted aryl group or an optionally substituted five membered or six membered non-aromatic heterocylic group fused to an optionally substituted monocylic aryl group. W and Y are independently a covalent bond or a C1-C3 substituted or unsubstituted alkylene group. X is a heteroatom-containing functional group, an aromatic heterocyclic group, substituted aromatic heterocyclic group, non-aromatic heterocyclic group, substituted non-aromatic heterocyclic group, an olefin group or a substituted olefin group. Also disclosed are methods of treating a subject with a disease associated with hyperphosphatemia, as well as a disease mediated by phosphate-transport function. The methods comprise the step of administering an effective amount of the one of the compounds described above.
