- Organic bifunctional catalyst and preparation method thereof as well as stereoregular biodegradable polyester and preparation method thereof
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The invention relates to an organic bifunctional catalyst and a preparation method thereof, and stereoregular biodegradable polyester and a preparation method thereof. The organic bifunctional catalyst disclosed by the invention is obtained by reacting isocyanate or isothiocyanate with a pyridylamine compound. According to the catalyst, an O-carboxyl intracyclic anhydride monomer and a pyridine nucleophilic addition monomer of an amino acid source are activated by thiourea, and controllable ring opening polymerization can be performed on an OCA monomer under a mild condition by utilizing an amplification effect of adjacent groups, so that functional polyester with high isotacticity and controllable molecular weight is prepared. The solvent used for polymerization can be chloroform, toluene, dichloromethane and the like, the polymerization temperature range is 25-50 DEG C, and the stereoregularity is adjustable between 60% and 90%. Under the polymerization condition, the monomer conversion rate can reach 99% within 24-48 hours. The molecular weight of the obtained polyester is controllable, and the melting point reaches up to 150 DEG C. The molecular weight of the polyester is changed between 20,000 and 100,000, and the polyester has a wide prospect for industrial application.
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Paragraph 0146-0148
(2021/07/10)
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- Synergetic Organocatalysis for Eliminating Epimerization in Ring-Opening Polymerizations Enables Synthesis of Stereoregular Isotactic Polyester
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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.
- Tao, Youhua,Li, Maosheng,Tao, Yue,Tang, Jiadong,Wang, Yanchao,Zhang, Xiaoyong,Wang, Xianhong
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supporting information
p. 281 - 289
(2019/01/04)
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- Intramolecular N-arylation in heterocyclization: synthesis of new pyrido-fused pyrrolo[1,2-a][1,4]diazepinones
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Alkylation of l-prolinamide with 3-(chloromethyl)-2-halopyridines, followed by cyclization through an intramolecular Pd-catalysed amidation, provided an entry to the pyrido[2,3-e]pyrrolo[1,2-a][1,4]diazepin-10-one scaffold. Furthermore, a synthetic route towards diverse new pyrido[f]pyrrolo[1,2-a][1,4]diazepin-7-ones has been developed by acylation of contiguously substituted (aminomethyl)halopyridines with Boc-l-proline followed by intramolecular amination.
- Legerén, Loreto,Domínguez, Domingo
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body text
p. 4053 - 4057
(2010/08/07)
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- Pyrimidine derivatives useful as inhibitors of PKC-theta
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Disclosed are novel compounds of formula (I): wherein X, Y, R1, R2 and R3 are as defined herein, which are useful as inhibitors of PKC-theta and are thus useful for treating a variety of diseases and disorders that are mediated or sustained through the activity of PKC-theta, including immunological disorders and type II diabetes. This invention also relates to pharmaceutical compositions comprising these compounds, methods of using these compounds in the treatment of various diseases and disorders, processes for preparing these compounds and intermediates useful in these processes.
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Page/Page column 94
(2008/06/13)
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- Aza-and polyaza-naphthalenly ketones useful as hiv integrase inhibitors
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Certain aza- and polyaza-naphthalenyl ketones including certain quinolinyl and naphthyridinyl ketones are described as inhibitors of HIV integrase and inhibitors of HIV replication. These compounds are useful in the prevention or treatment of infection by HIV and the treatment or the delay in the onset of AIDS, as compounds or pharmaceutically acceptable salts, or as ingredients in pharmaceutical compositions, optionally in combination with other antivirals, immunomodulators, antibiotics or vaccines. Methods of treating or delaying the onset of AIDS and methods of preventing or treating infection by HIV are also described.
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Page/Page column 48
(2010/02/10)
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- Design and synthesis of 8-hydroxy-[1,6]naphthyridines as novel inhibitors of HIV-1 integrase in vitro and in infected cells
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Naphthyridine 7 inhibits the strand transfer of the integration process catalyzed by integrase with an IC50 of 10 nM and inhibits 95% of the spread of HIV-1 infection in cell culture at 0.39 μM. It does not exhibit cytotoxicity in cell culture
- Zhuang, Linghang,Wai, John S.,Embrey, Mark W.,Fisher, Thorsten E.,Egbertson, Melissa S.,Payne, Linda S.,Guare Jr., James P.,Vacca, Joseph P.,Hazuda, Daria J.,Felock, Peter J.,Wolfe, Abigail L.,Stillmock, Kara A.,Witmer, Marc V.,Moyer, Gregory,Schleif, William A.,Gabryelski, Lori J.,Leonard, Yvonne M.,Lynch Jr., Joseph J.,Michelson, Stuart R.,Young, Steven D.
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p. 453 - 456
(2007/10/03)
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