67938-76-5Relevant articles and documents
Synergetic Organocatalysis for Eliminating Epimerization in Ring-Opening Polymerizations Enables Synthesis of Stereoregular Isotactic Polyester
Tao, Youhua,Li, Maosheng,Tao, Yue,Tang, Jiadong,Wang, Yanchao,Zhang, Xiaoyong,Wang, Xianhong
supporting information, p. 281 - 289 (2019/01/04)
Ring-opening polymerization of O-carboxyanhydrides (OCAs) can furnish polyesters with a diversity of functional groups that are traditionally hard to harvest by polymerization of lactones. Typical ring-opening catalysts are subject to unavoidable racemization of most OCA monomers, which hampers the synthesis of highly isotactic crystalline polymers. Here, we describe an effective bifunctional single-molecule organocatalysis for selective ring-opening polymerization of OCAs without epimerization. The close vicinity of both activating groups in the same molecule engenders an amplified synergetic effect and thus allows for the use of mild bases, thereby leading to minimal epimerization for polymerization. Ring-opening polymerization of manOCA monomer (OCA from mandelic acid) mediated by the bifunctional single-molecule organocatalyst yields highly isotactic poly(mandelic acid) (PMA) with controlled molecular weights (up to 19.8 kg mol-1). Mixing of the two enantiomers of PMA generates the first example of a crystalline stereocomplex in this area, which displayed distinct Tm values around 150 °C. Remarkably, the bifunctional catalysts are moisture-stable, recyclable, and easy to use, allowing sustainable and scalable synthesis of a stereoregular functional polyester.
SOLUBLE GUANYLATE CYCLASE ACTIVATORS
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Page/Page column 88, (2011/12/14)
A compound of Formula (I): or a pharmaceutically acceptable salt thereof, are capable of modulating the body's production of cyclic guanosine monophosphate ("cGMP") and are generally suitable for the therapy and prophylaxis of diseases which are associated with a disturbed cGMP balance. The invention furthermore relates to processes for preparing compounds of Formula I , or a pharmaceutically acceptable salt thereof, for their use in the therapy and prophylaxis of the above mentioned diseases and for preparing pharmaceuticals for this purpose, and to pharmaceutical preparations which comprise compounds of Formula (I) or a pharmaceutically acceptable salt thereof
HIV INTEGRASE INHIBITORS
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Page/Page column 21-22, (2010/11/27)
The invention encompasses a series bicyclic pyrimidinone compounds of Formula I which inhibit HIV integrase and prevent viral integration into human DNA. This action makes the compounds useful for treating HIV infection and AIDS. The invention also encompasses pharmaceutical compositions and methods for treating those infected with HIV.