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21.
22.
Andrei Hutanu Steffen Kiessig Andrea Bathke Rolf Ketterer Sonja Riner Jan Olaf Stracke Markus Wild Bernd Moritz 《Electrophoresis》2019,40(22):3014-3022
Charge heterogeneity profiling is important for the quality control (QC) of biopharmaceuticals. Because of the increasing complexity of these therapeutic entities [1], the development of alternative analytical techniques is needed. In this work, flow‐through partial‐filling affinity capillary electrophoresis (FTPFACE) has been established as a method for the analysis of a mixture of two similar monoclonal antibodies (mAbs). The addition of a specific ligand results in the complexation of one mAb in the co‐formulation, thus changing its migration time in the electric field. This allows the characterization of the charged variants of the non‐shifted mAb without interferences. Adsorption of proteins to the inner capillary wall has been circumvented by rinsing with guanidine hydrochloride before each injection. The presented FTPFACE approach requires only very small amounts of ligands and provides complete comparability with a standard CZE of a single mAb. 相似文献
23.
Stanković S Catak S D'hooghe M Goossens H Abbaspour Tehrani K Bogaert P Waroquier M Van Speybroeck V De Kimpe N 《The Journal of organic chemistry》2011,76(7):2157-2167
The synthetic utility of N-alkylidene-(2,3-dibromo-2-methylpropyl)amines and N-(2,3-dibromo-2-methylpropylidene)benzylamines was demonstrated by the unexpected synthesis of 3-methoxy-3-methylazetidines upon treatment with sodium borohydride in methanol under reflux through a rare aziridine to azetidine rearrangement. These findings stand in contrast to the known reactivity of the closely related N-alkylidene-(2,3-dibromopropyl)amines, which are easily converted into 2-(bromomethyl)aziridines under the same reaction conditions. A thorough insight into the reaction mechanism was provided by both experimental study and theoretical rationalization. 相似文献
24.
Microphysiometry was used to evaluate the effects of terpene trilactone and flavonoid constituents of Ginkgo biloba on human platelet‐activating‐factor receptor (PAFR). Inhibition of the platelet‐activating factor response by terpene trilactones was confirmed using this functional assay. Ginkgolide B (GB) and 10‐O‐benzyl‐GB showed the strongest inhibition (81 and 93%, resp.) of the PAFR response, while the flavonoids rutin, quercetin, and kaempferol showed negligible response inhibition. G. biloba extract mixtures were also tested, and results indicate possible synergistic effects among various components. 相似文献
25.
Bühl M Grigoleit S Kabrede H Mauschick FT 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,12(2):477-488
59Co chemical shifts were computed at the GIAO-B3LYP level for [Co(CN)6]3-, [Co(H2O)6]3+, [Co(NH3)6]3+, and [Co(CO)4]- in water. The aqueous solutions were modeled by Car-Parrinello molecular dynamics (CPMD) simulations, or by propagation on a hybrid quantum-mechanical/molecular-mechanical Born-Oppenheimer surface (QM/MM-BOMD). Mean absolute deviations from experiment obtained with these methods are on the order of 400 and 600 ppm, respectively, over a total delta(59Co) range of about 18,000 ppm. The effect of the solvent on delta(59Co) is mostly indirect, resulting primarily from substantial metal-ligand bond contractions on going from the gas phase to the bulk. The simulated solvent effects on geometries and delta(59Co) values are well reproduced by using a polarizable continuum model (PCM), based on optimization and perturbational evaluation of quantum-mechanical zero-point corrections. 相似文献
26.
Olga Bienemann Ann‐Kathrin Froin Ines dos Santos Vieira Ramona Wortmann Alexander Hoffmann Prof. Dr. Sonja Herres‐Pawlis 《无机化学与普通化学杂志》2012,638(11):1683-1690
This contribution reports the synthesis of the novel tetradentate bisguanidine ligand 2′,2′‐[ethane‐1, 2‐diylbis(methylazanediyl)]bis(ethane‐2, 1‐diyl)bis(1, 1, 3, 3‐tetramethylguanidine) ( L1 , TMG2dmtrien), which combines two weak amine and two strong guanidine donor functions. Two new copper(II) complexes were isolated and structurally characterized as complexes [Cu(TMG2dmtrien)][Br]2 · 3MeCN ( C1 [Br]2 · 3MeCN) and [Cu(TMG2dmtrien)][Cl]2 · 3MeCN ( C2 [Cl]2 · 3MeCN). The cations C1 and C2 [Cu(TMG2dmtrien)]2+ show a square‐planar coordination environment and are chiral with both enantiomers being observed in the unit cell. We investigated the application of L1 in copper‐mediated styrene ATRP. L1 shows with CuBr and PEBr as initiator a high polymerization activity according to the polymerization rate. First order kinetics confirm the living character of the polymerization. However, the deviation of molecular weights from theoretical molecular weights and the broad molecular weight distributions hint for a low controlled ATRP. The ATRP with further copper(I) salts {CuCl, [Cu(MeCN)4]BF4 and [Cu(MeCN)4]PF6} and PECl and PEBr as initiators were investigated as well. Herein the use of [Cu(MeCN)4]PF6 with PECl led to promising results. 相似文献
27.
Novel representatives of the important group of biologically active dibenzosuberone derivatives were prepared: 3,7-dibromo-5-(dimethylaminoethyl- oxyimino)-10,11-dihydro-5H-dibenzo[a,d]cyclohepta-1,4-diene (1), 3,7-dibromo-5-(3- dimethylaminopropylidene)-10,11-dihydro-5H-dibenzo[a,d]cycloheptene (2) and 1,7- dibromo-5-(3-dimethylaminopropylidene)-10,11-dihydro-5H-dibenzo-[a,d]-cycloheptene (3). These compounds are potential tricyclic antidepressants (TCAs), which are still the most frequently prescribed antidepressants in many countries. 相似文献
28.
Adam Neuba Dr. Sonja Herres‐Pawlis Oliver Seewald Janna Börner Andreas J. Heuwing Ulrich Flörke Prof. Dr. Gerald Henkel 《无机化学与普通化学杂志》2010,636(15):2641-2649
The transition metal complexes with the ligand 1,3‐bis(N,N,N′,N′‐tetramethylguanidino)propane (btmgp), [Mn(btmgp)Br2] ( 1 ), [Co(btmgp)Cl2] ( 2 ), [Ni(btmgp)I2] ( 3 ), [Zn(btmgp)Cl2] ( 4 ), [Zn(btmgp)(O2CCH3)2] ( 5 ), [Cd(btmgp)Cl2] ( 6 ), [Hg(btmgp)Cl2] ( 7 ) and [Ag2(btmgp)2][ClO4]2·2MeCN ( 8 ), were prepared and characterised for the first time. The stoichiometric reaction of the corresponding water‐free metal salts with the ligand btmgp in dry MeCN or THF resulted in the straightforward formation of the mononuclear complexes 1 – 7 and the binuclear complex 8 . In complexes with MII the metal ion shows a distorted tetrahedral coordination whereas in 8 , the coordination of the MI ion is almost linear. The coordination behavior of btmgp and resulting structural parameters of the corresponding complexes were discussed in an comparative approach together with already described complexes of btmgp and the bisguanidine ligand N1,N2‐bis(1,3‐dimethylimidazolidin‐2‐ylidene)‐ethane‐1,2‐diamine (DMEG2e), respectively. 相似文献
29.
Janna Börner M. Sc. Ulrich Flörke Dr. Klaus Huber Prof. Dr. Artjom Döring Dipl.‐Chem. Dirk Kuckling Prof. Dr. Sonja Herres‐Pawlis Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(10):2362-2376
New class of air‐stable catalysts for lactide polymerisation: Guanidine–pyridine hybrid ligands (picture, left) were used to prepare a series of zinc complexes (e.g., depicted cation [ZnL2(CF3SO3)]+, where L is the quinoline‐containing ligand with R1=R2=R3=R4=Me), in which the ligand binds through two different N‐donor atoms. The zinc complexes show high activity in ring‐opening polymerisation of d,l ‐lactide (right), giving polylactide with molecular masses up to 176 000 g mol?1 and in high yield.
30.
Sonja Herres‐Pawlis Dr. Tarimala Seshadri Ulrich Flörke Gerald Henkel Prof. Dr. 《无机化学与普通化学杂志》2009,635(8):1209-1214
The reaction of 2,2′‐Bis(2N‐(1,1′,3,3′‐tetramethyl‐guanidino))diphenylene‐amine (TMG2PA) ( 1 ) with CuI in MeCN results in the formation of [CuII(TMG2PAamid)I] ( 2 ) indicatingthat CuI is the target of an oxidative attack of the N‐H proton of the ligand which itself is converted to molecular hydrogen. In contrast, if [Cu(MeCN)4][PF6] is used as the CuI source, [CuI2(TMGbenz)2][PF6]2 ( 3 ) is obtained instead. The use of the non‐coordinating counterion [PF6]– apparently prevents CuI from oxidation but induces itself a cyclisation reaction within the ligand which results in the formation of a benzimidazole‐guanidine ligand. 相似文献