- Tuning a robust system: N,O zinc guanidine catalysts for the ROP of lactide
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Non-toxic, highly active and robust complexes are the holy grail as ideal green catalysts for the polymerisation of biorenewable and biodegradable polylactide. Four new zinc guanidine complexes [ZnCl2(TMG4NMe2asme)], [ZnCl2(TMG5Clasme)], [ZnCl2(TMG5Measme)] and [ZnCl2(TMG5NMe2asme)] with different electron-donating and electron-withdrawing groups on the ligand's aromatic backbone have been synthesised. Ligands are derived from low-cost commercially available compounds and have been converted by a three- or four-step synthesis process into the desired ligand in good yields. The compounds have been fully characterised and tested in the ROP of rac-LA under industrially relevant conditions. The complexes are based on the recently published structure [ZnCl2(TMGasme)] which has shown high activity in the polymerisation of lactide at 150 °C. Different substituents in the para-position of the guanidine moiety significantly increase the polymerisation rate whereas positioning substituents in the meta-position causes no change in the reaction rate. With molecular weights over 71000 g mol-1 being achievable, the best system produces polymers for multiple industrial applications and its polymerisation rate approaches that of Sn(Oct)2. The robust systems are able to polymerise non-purified lactide. The initiation of the polymerisation is suggested to occur due to impurities in the monomer.
- Sch?fer, Pascal M.,McKeown, Paul,Fuchs, Martin,Rittinghaus, Ruth D.,Hermann, Alina,Henkel, Johanna,Seidel, Sebastian,Roitzheim, Christoph,Ksiazkiewicz, Agnieszka N.,Hoffmann, Alexander,Pich, Andrij,Jones, Matthew D.,Herres-Pawlis, Sonja
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p. 6071 - 6082
(2019/05/17)
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- COMPOUNDS AND METHODS FOR 18F LABELED AGENTS
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The present invention relates to novel compounds suitable for or already radiolabeled with 18F, methods of making such compounds and use of such compounds for diagnostic imaging. Such labeled compounds are characterized by Formula II, wherein the substituents G, Q, L, Y and U have the meaning as defined in the specification and claims.
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Page/Page column 129
(2010/11/30)
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- Compounds and methods for F labelled agents
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This invention relates to novel compounds suitable for or already radiolabeled with 18F, methods of making such compounds and use of such compounds for diagnostic imaging. Such labeled compounds are characterized by Formula 11, wherein the subs
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- Novel phenylalanine derivatives
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Specific phenylalanine derivatives and analogues thereof have an antagonistic activity to α4 integrin. They are used as therapeutic agents for various diseases concerning α4 integrin.
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Page/Page column 42-43
(2010/02/14)
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- PROCESS FOR PRODUCING PHENYLALANINE DERIVATIVE HAVING QUINAZOLINEDIONE SKELETON AND INTERMEDIATE FOR THE SAME
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The present invention provides a method for producing a phenylalanine derivative(s) having a quinazolinedione ring of formula (5), including steps comprising of:reacting an acylphenylalanine derivative(s) of formula (1) with a carbonyl group-introducing r
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Page/Page column 14
(2010/02/14)
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