Mechanistic Aspects of the Polymerization of Lactide Using a Highly Efficient Aluminum(III) Catalytic System

bibtex: ISI:000400802300037 bibtex\location:'1155 16TH ST, NW, WASHINGTON, DC 20036 USA',publisher:'AMER CHEMICAL SOC',type:'Article',affiliation:'Thomas, CM (Reprint Author), PSL Res Univ, Chim ParisTech, CNRS, Inst Rech Chim Paris, F-75005 Paris, France. Maron, L (Reprint Author), Univ Toulouse, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, L (Reprint Author), UPS, INSA, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, L (Reprint Author), IRSAMC, LPCNO, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, L (Reprint Author), CNRS, F-31077 Toulouse, France. Maron, L (Reprint Author), IRSAMC, UMR 5215, F-31077 Toulouse, France. Robert, Carine; Schmid, Thibault E.; Richard, Vincent; Haquette, Pierre; Raman, Sumesh K.; Rager, Marie-Noelle; Thomas, Christophe M., PSL Res Univ, Chim ParisTech, CNRS, Inst Rech Chim Paris, F-75005 Paris, France. Gauvin, Regis M.; Morin, Yohann, Univ Lille, Univ Artois, CNRS, Cent Lille,ENSCL,UCCS,UMR 8181, F-59000 Lille, France. Trivelli, Xavier, Univ Lille, CNRS, UGSF, UMR 8576, F-59000 Lille, France. Guerineau, Vincent, Univ Paris Sud, Univ Paris Saclay, CNRS UPR2301, Inst Chim Subst Nat, Ave Terrasse, F-91198 Gif Sur Yvette, France. del Rosal, Iker; Maron, Laurent, Univ Toulouse, 135 Ave Rangueil, F-31077 Toulouse, France. del Rosal, Iker; Maron, Laurent, UPS, INSA, 135 Ave Rangueil, F-31077 Toulouse, France. del Rosal, Iker; Maron, Laurent, IRSAMC, LPCNO, 135 Ave Rangueil, F-31077 Toulouse, France. del Rosal, Iker; Maron, Laurent, CNRS, F-31077 Toulouse, France. del Rosal, Iker; Maron, Laurent, IRSAMC, UMR 5215, F-31077 Toulouse, France.','author-email':'[email protected] [email protected]',da:'2018-12-05','doc-delivery-number':'EU1SV','funding-acknowledgement':'ENSCP; ANR [ANR-10-PDOC-010-01]; Fondation Pierre-Gilles de Gennes; CNRS; CALMIP-EOS [p0833]; CNRS [TGIR-RMN-THC Fr3050]','funding-text':'ENSCP, ANR (grant ANR-10-PDOC-010-01), Fondation Pierre-Gilles de Gennes, and CNRS are thanked for financial support of this work. This work was performed using HPC resources from CALMIP-EOS (grant p0833). We would like to thank Purac for a generous loan of rac-lactide. C.M.T. is grateful to the Institut Universitaire de France (IUF). Financial support from the TGIR-RMN-THC Fr3050 CNRS for conducting the research is gratefully acknowledged.','journal-iso':'J. Am. Chem. Soc.','keywords-plus':'RING-OPENING POLYMERIZATION; CHROMIUM SALEN COMPLEXES; QUATERNARY ORGANIC SALT; CARBON-DIOXIDE; PROPYLENE-OXIDE; RAC-LACTIDE; STEREOSELECTIVE POLYMERIZATION; ALTERNATING COPOLYMERIZATION; CYCLIC CARBONATES; RACEMIC LACTIDE','number-of-cited-references':'85','orcid-numbers':'Del Rosal, Iker/0000-0001-6898-4550 Gauvin, Regis/0000-0002-4788-4363 Guerineau, Vincent/0000-0002-1747-5016 Thomas, Christophe/0000-0001-8014-4255','research-areas':'Chemistry','researcherid-numbers':'Del Rosal, Iker/H-3419-2012','times-cited':'12','unique-id':'ISI:000400802300037','usage-count-last-180-days':'13','usage-count-since-2013':'83','web-of-science-categories':'Chemistry, Multidisciplinary'\International audienceWe report here a unique example of an in situ generated aluminum initiator stabilized by a C-2-symmetric salen ligand which shows a hitherto unknown high activity for the ROP of rac-lactide at room temperature. Using a simple and robust catalyst system, which is prepared from a salen complex and an onium salt, this convenient route employs readily available reagents that afford polylactide in good yields with narrow polydispersity indices, without the need for time-consuming and expensive processes that are typically required for catalyst preparation and purification. In line with the experimental evidence, DFT studies reveal that initiation and propagation proceed via an external alkoxide attack on the coordinated monomer

Mechanistic Aspects of the Polymerization of Lactide Using a Highly Efficient Aluminum(III) Catalytic System

bibtex: ISI:000400802300037 bibtex\location:'1155 16TH ST, NW, WASHINGTON, DC 20036 USA',publisher:'AMER CHEMICAL SOC',type:'Article',affiliation:'Thomas, CM (Reprint Author), PSL Res Univ, Chim ParisTech, CNRS, Inst Rech Chim Paris, F-75005 Paris, France. Maron, L (Reprint Author), Univ Toulouse, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, L (Reprint Author), UPS, INSA, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, L (Reprint Author), IRSAMC, LPCNO, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, L (Reprint Author), CNRS, F-31077 Toulouse, France. Maron, L (Reprint Author), IRSAMC, UMR 5215, F-31077 Toulouse, France. Robert, Carine; Schmid, Thibault E.; Richard, Vincent; Haquette, Pierre; Raman, Sumesh K.; Rager, Marie-Noelle; Thomas, Christophe M., PSL Res Univ, Chim ParisTech, CNRS, Inst Rech Chim Paris, F-75005 Paris, France. Gauvin, Regis M.; Morin, Yohann, Univ Lille, Univ Artois, CNRS, Cent Lille,ENSCL,UCCS,UMR 8181, F-59000 Lille, France. Trivelli, Xavier, Univ Lille, CNRS, UGSF, UMR 8576, F-59000 Lille, France. Guerineau, Vincent, Univ Paris Sud, Univ Paris Saclay, CNRS UPR2301, Inst Chim Subst Nat, Ave Terrasse, F-91198 Gif Sur Yvette, France. del Rosal, Iker; Maron, Laurent, Univ Toulouse, 135 Ave Rangueil, F-31077 Toulouse, France. del Rosal, Iker; Maron, Laurent, UPS, INSA, 135 Ave Rangueil, F-31077 Toulouse, France. del Rosal, Iker; Maron, Laurent, IRSAMC, LPCNO, 135 Ave Rangueil, F-31077 Toulouse, France. del Rosal, Iker; Maron, Laurent, CNRS, F-31077 Toulouse, France. del Rosal, Iker; Maron, Laurent, IRSAMC, UMR 5215, F-31077 Toulouse, France.','author-email':'[email protected] [email protected]',da:'2018-12-05','doc-delivery-number':'EU1SV','funding-acknowledgement':'ENSCP; ANR [ANR-10-PDOC-010-01]; Fondation Pierre-Gilles de Gennes; CNRS; CALMIP-EOS [p0833]; CNRS [TGIR-RMN-THC Fr3050]','funding-text':'ENSCP, ANR (grant ANR-10-PDOC-010-01), Fondation Pierre-Gilles de Gennes, and CNRS are thanked for financial support of this work. This work was performed using HPC resources from CALMIP-EOS (grant p0833). We would like to thank Purac for a generous loan of rac-lactide. C.M.T. is grateful to the Institut Universitaire de France (IUF). Financial support from the TGIR-RMN-THC Fr3050 CNRS for conducting the research is gratefully acknowledged.','journal-iso':'J. Am. Chem. Soc.','keywords-plus':'RING-OPENING POLYMERIZATION; CHROMIUM SALEN COMPLEXES; QUATERNARY ORGANIC SALT; CARBON-DIOXIDE; PROPYLENE-OXIDE; RAC-LACTIDE; STEREOSELECTIVE POLYMERIZATION; ALTERNATING COPOLYMERIZATION; CYCLIC CARBONATES; RACEMIC LACTIDE','number-of-cited-references':'85','orcid-numbers':'Del Rosal, Iker/0000-0001-6898-4550 Gauvin, Regis/0000-0002-4788-4363 Guerineau, Vincent/0000-0002-1747-5016 Thomas, Christophe/0000-0001-8014-4255','research-areas':'Chemistry','researcherid-numbers':'Del Rosal, Iker/H-3419-2012','times-cited':'12','unique-id':'ISI:000400802300037','usage-count-last-180-days':'13','usage-count-since-2013':'83','web-of-science-categories':'Chemistry, Multidisciplinary'\International audienceWe report here a unique example of an in situ generated aluminum initiator stabilized by a C-2-symmetric salen ligand which shows a hitherto unknown high activity for the ROP of rac-lactide at room temperature. Using a simple and robust catalyst system, which is prepared from a salen complex and an onium salt, this convenient route employs readily available reagents that afford polylactide in good yields with narrow polydispersity indices, without the need for time-consuming and expensive processes that are typically required for catalyst preparation and purification. In line with the experimental evidence, DFT studies reveal that initiation and propagation proceed via an external alkoxide attack on the coordinated monomer

Terminal Complement Inhibitor Eculizumab in Atypical Hemolytic-Uremic Syndrome

Background Atypical hemolytic-uremic syndrome is a genetic, life-threatening, chronic disease of complement-mediated thrombotic microangiopathy. Plasma exchange or infusion may transiently maintain normal levels of hematologic measures but does not treat the underlying systemic disease. Methods We conducted two prospective phase 2 trials in which patients with atypical hemolytic-uremic syndrome who were 12 years of age or older received eculizumab for 26 weeks and during long-term extension phases. Patients with low platelet counts and renal damage (in trial 1) and those with renal damage but no decrease in the platelet count of more than 25% for at least 8 weeks during plasma exchange or infusion (in trial 2) were recruited. The primary end points included a change in the platelet count (in trial 1) and thrombotic microangiopathy event-free status (no decrease in the platelet count of >25%, no plasma exchange or infusion, and no initiation of dialysis) (in trial 2). Results A total of 37 patients (17 in trial 1 and 20 in trial 2) received eculizumab for a median of 64 and 62 weeks, respectively. Eculizumab resulted in increases in the platelet count; in trial 1, the mean increase in the count from baseline to week 26 was 73x10(9) per liter (P<0.001). In trial 2, 80% of the patients had thrombotic microangiopathy event-free status. Eculizumab was associated with significant improvement in all secondary end points, with continuous, time-dependent increases in the estimated glomerular filtration rate (GFR). In trial 1, dialysis was discontinued in 4 of 5 patients. Earlier intervention with eculizumab was associated with significantly greater improvement in the estimated GFR. Eculizumab was also associated with improvement in health-related quality of life. No cumulative toxicity of therapy or serious infection-related adverse events, including meningococcal infections, were observed through the extension period. Conclusions Eculizumab inhibited complement-mediated thrombotic microangiopathy and was associated with significant time-dependent improvement in renal function in patients with atypical hemolytic-uremic syndrome