The structure determination of major allergens is a prerequisite for analyzing surface exposed areas of the allergen and for mapping conformational epitopes. These may be determined by experimental methods including crystallographic and NMR-based approaches or predicted by computational methods. In this review we summarize the existing structural information on allergens and their classification in protein fold families. The currently available allergen-antibody complexes are described and the experimentally obtained epitopes compared. Furthermore we discuss established methods for linear and conformational epitope mapping, putting special emphasis on a recently developed approach, which uses the structural similarity of proteins in combination with the experimental cross-reactivity data for epitope prediction.

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Substitution reactions of rhenium(V) oxo precursors [ReOCl3(PPh3)2] or [NBu4][ReOCl4] with the bidentate acetylacetone-derived ketoamine ligands APOH = 4-anilino-3-penten-2-one, DPOH = 4-[2,6-dimethylanilino]-3-penten-2-one, and MTPOH = 4-[2-(methylthio)anilino]-3-penten-2-one gave the complexes [ReO(APO)Cl2(PPh3)] (1), [ReO(DPO)Cl2(PPh3)] (2), and [NBu4][ReOLCl3] (3, L = APO; 4, L = DPO; 5, L = MTPO), respectively. All complexes exhibit only one ketoamino chelate, independent of the amount of ligand added to the rhenium precursors. The complexes were characterized by 1H and 13C NMR spectroscopy. X-ray crystal structures of the complexes 1, 2, 4, and 5, including that of MTPOH, were determined, revealing the trans position of the two oxygen atoms and the trans-Cl,Cl conformation in 1 and 2, in contrast to most other rhenium complexes of this type where the cis-Cl,Cl conformation is observed. Coordination of the potentially tridentate ligand MTPOH in 5 is bidentate with a dangling thioether substituent. Compound 2 shows catalytic activity in the oxidation of cis-cyclooctene with tert-butylhydroperoxide.

Molybdenum dioxo compounds [MoO2Cl(eta 2-pz)] and [MoO2(eta 2-pz)2] with pz = eta (2)-3,5-di-tert-butylpyrazolate have been synthesized; crystallographic data, catalytic activity, and oxo transfer properties are described.

The synthesis of N-heterocyclic carbene adducts of alkynyl lithium and magnesium is achieved, and different degrees of association are observed. Reaction of strontium amide nacnacSrN(SiMe(3))(2)(thf) (nacnac = CH(CMe2,6-iPr(2)C(6)H(3)N)(2)) with PhC[triple bond]CH in THF yields the dimeric alkynyl complex [nacnacSr(thf)(mu-C[triple bond]CPh)](2) which shows an interesting coordination geometry around the metal center. The compound retains the THF molecules, unlike its lighter congener, even in hydrocarbon solvents.

Carrier-bound Der p 2 peptides should allow avoiding IgE-mediated side-effects, and because of their low potential to activate allergen-specific T cells, they may reduce late-phase side-effects during SIT. Further, these peptides may be also useful for prophylactic vaccination.

The fluorosilylhydroxylamine tBuSiF(Me)−ONH2 (2) is obtained in the reaction of tBuSiF(Me)−NHtBu (1) and HONH2·HCl. The reaction of tBuSiMe2−ONH2 with butyllithium leads to the formation of the bis(silyl)hydroxylamine tBuSiMe2−NH−O−SiF(Me)tBu (3). Depending on the bulkiness of the substituents and the solvent, lithium salts of N,O-bis(silyl)hydroxylamines crystallize as dimeric, trimeric, or tetrameric O-lithium-N,N-bis(silyl)hydroxylamides, e.g., [(tBuSiMe2)2N−OLi·THF]2, [(tBuSiMe2)2N−OLi]3 (4), and [tBuSiMe2(Me3Si)N−OLi]4 (6). Lithiation of tBuSiMe2ONHSiMe2 tBu in the presence of TMEDA leads to a cleavage of the N−O bond. The hexameric lithium silanolate (tBuSiMe2O−Li)6 (5) is obtained. Above 0 °C the lithium derivative of 3 (3a) reacts with LiF and the cyclic silylhydroxylamine (tBuSiMe-O−N−SiMe2 tBu)2 (7). In the reactions of 3a and 6 with F2SiMe2 and F3SiMe the first asymmetrical tris(silyl)hydroxylamines N,N-tBuSiMe2(FSi(Me)tBu)N−O−SiFMe2 (8), N,N-tBuSiMe2(SiMe3)N−O−SiFMe2 (9), N,N-tBuSiMe2(SiMe3)N−O−SiF2Me (10), and the bis((bis)(silyl)hydroxylamino)silane [N,N-tBuSiMe2(SiMe3)]2−O−SiFMe (11) are isolated. Chlorodimethylalane reacts with the trimeric O-lithium-N,N-bis(tert-butyldimethylsilyl)hydroxylamide to give LiCl and the four-membered ring system 2,4-bis-N,N-bis(tert-butyldimethylsilylhydroxylamide)-1-dimethylalano-3-lithio-2,4-dioxocyclobutane (12). Crystal structures of 4−7 and 12 are reported.

The European X-ray Free-Electron Laser Facility in Germany delivers x-ray pulses with femtosecond pulse duration at a repetition rate of up to 4.5 MHz. The free-electron laser radiation is created by the self-amplified spontaneous emission (SASE) process, whose stochastic nature gives rise to shot-to-shot fluctuations in most beam properties, including spectrum, pulse energy, spatial profile, wavefront, and temporal profile. Each spectrum consisting of many spikes varies in width and amplitude that appear differently within the envelope of the SASE spectrum. In order to measure and study the SASE spectrum, the HIgh REsolution hard X-ray single-shot (HIREX) spectrometer was installed in the photon tunnel of the SASE1 undulator beamline. It is based on diamond gratings, bent crystals as a dispersive element, and a MHz-repetitionrate strip detector. It covers a photon energy range of 3 keV-25 keV and a bandwidth of 0.5% of the SASE beam. The SASE spikes are resolved with 0.15 eV separation using the Si 440 reflection, providing a resolving power of 60 000 at a photon energy of 9.3 keV. The measured SASE bandwidth is 25 eV. In this paper, we discuss the design specifications, installation, and commissioning of the HIREX spectrometer. The spectral results using Si (110), Si (111), and C (110) crystals are presented.