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51.
Simonato S Gröger H Möllmer J Staudt R Puls A Dreisbach F Feldmann C 《Chemical communications (Cambridge, England)》2012,48(6):844-846
The CO(2) uptake on nanoscale AlO(OH) hollow spheres (260 mg g(-1)) as a new material is comparable to that on many metal-organic frameworks although their specific surface area is much lower (530 m(2) g(?1)versus 1500-6000 m(2) g(?1)). Suited temperature-pressure cycles allow for reversible storage and separation of CO(2) while the CO(2) uptake is 4.3-times higher as compared to N(2). 相似文献
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Su XC Man B Beeren S Liang H Simonsen S Schmitz C Huber T Messerle BA Otting G 《Journal of the American Chemical Society》2008,130(32):10486-10487
A new lanthanide tag was designed for site-specific labeling of proteins with paramagnetic lanthanide ions. The tag, 4-mercaptomethyl-dipicolinic acid, binds lanthanide ions with nanomolar affinity, is readily attached to proteins via a disulfide bond, and avoids the problems of diastereomer formation associated with most of the conventional lanthanide tags. The high lanthanide affinity of the tag opens the possibility to measure residual dipolar couplings in a single sample containing a mixture of paramagnetic and diamagnetic lanthanides. Using the DNA-binding domain of the E. coli arginine repressor as an example, it is demonstrated that the tag allows immobilization of the lanthanide ion in close proximity of the protein by additional coordination of the lanthanide by a carboxyl group of the protein. The close proximity of the lanthanide ion promotes accurate determinations of magnetic susceptibility anisotropy tensors. In addition, the small size of the tag makes it highly suitable for studies of intermolecular interactions. 相似文献
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A Catalytic Oxidative Quinone Heterofunctionalization Method: Synthesis of Strongylophorine‐26
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Kristian M. Jacobsen Henriette N. Tobiesen Line Clemmensen Prof. Dr. Thomas B. Poulsen 《Angewandte Chemie (International ed. in English)》2018,57(31):9805-9809
The preparation of heteroatom‐substituted p‐quinones is ideally performed by direct addition of a nucleophile followed by in situ reoxidation. Albeit an appealing strategy, the reactivity of the p‐quinone moiety is not easily tamed and no broadly applicable method for heteroatom functionalization exists. Shown herein is that Co(OAc)2 and Mn(OAc)3?2 H2O act as powerful catalysts for oxidative p‐quinone functionalization with a collection of O, N, and S nucleophiles, using oxygen as the terminal oxidant. Preliminary mechanistic observations and the first synthesis of the cytotoxic natural product strongylophorine‐26 is presented. 相似文献
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Henriette M. Hansen 《Tetrahedron》2005,61(42):9955-9960
A new and convergent synthesis of azaphenanthridines via an anionic ring closure is reported. Ortho-lithiation/in situ borylation of cyanopyridines produces the corresponding cyanopyridylboronic esters, which undergo a Suzuki-Miyaura cross-coupling to give the key intermediates. Addition of lithium morpholide produces the azaphenanthridines. 相似文献
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Henriette Lissau Martyn Jevric Anders
stergaard Madsen Mogens Brndsted Nielsen 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(6):452-455
π‐Conjugated donor–acceptor systems based on dithiafulvene (DTF) donor units and various acceptor units have attracted attention for their linear and nonlinear optical properties. The reaction between p‐benzoquinone and a 1,3‐dithiole phosphonium salt, deprotonated by lithium hexamethyldisilazide (LiHMDS), gave a product mixture from which the Michael adduct [systematic name: dimethyl 2‐(3‐hydroxy‐6‐oxocyclohexa‐2,4‐dien‐1‐ylidene)‐2H‐1,3‐dithiole‐4,5‐dicarboxylate], C13H10O6S2, was isolated. It is likely that one of the unidentified products obtained previously by others from related reactions could be a similar Michael adduct. 相似文献