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991.
The three‐component reaction of 2‐alkynylbenzaldoximes and α,β‐unsaturated carbonyl compounds with bromine or iodine monochloride is described, which generates the unexpected 2‐(4‐haloisoquinolin‐1‐yl)ethanol derivatives in good to excellent yields. 相似文献
992.
993.
An efficient and practical asymmetric synthesis of highly enantiomerically enriched α‐allenylglycines by room temperature indium‐mediated allenylation of chiral N‐tert‐butanesulfinyl imino esters with propargylic halides is described. The synthetic utilities of the approach were demonstrated by the rapid and convenient preparation of challenging cis‐substituted proline derivatives. 相似文献
994.
Bruno Almeida Dr. Jesús Joglar María Jesús Luque Rojas Juan Manuel Decara Francisco Javier Bermúdez‐Silva Dr. Manuel Macias‐González Dr. Montserrat Fitó Miguel Romero‐Cuevas Dr. Magí Farré Dr. María Isabel Covas Dr. Fernando Rodríguez de Fonseca Dr. Rafael de la Torre 《ChemMedChem》2010,5(10):1781-1787
A series of fatty acid amides of 3,4‐methylenedioxymethamphetamine (MDMA) catechol metabolites were synthesized in order to evaluate their biological activities. Upon administration, all synthesized compounds resulted in negative modulation of food intake in rats. The most active compounds have affinity for the CB1 receptor and/or PPAR‐α; part of their biological activity may be caused by these double interactions. 相似文献
995.
In this paper, we develop a computational model for the anisotropic plastic response of β‐HMX molecular crystals based upon experimental data. While phenomenological models of β‐HMX currently exist, they are inadequate as they cannot account for the orientation dependence of the observed response. The proposed model, on the other hand, successfully predicts the experimentally observed highly anisotropic and orientation dependent yield surfaces of β‐HMX molecular crystals having different crystal orientations. The model also correctly predicts the anisotropic plastic yielding of β‐HMX under uniaxial compression at different temperatures along different crystallographic directions. The model presented in this paper may be extended to predict the yielding and elastic–plastic deformation of other energetic molecular crystals. 相似文献
996.
Die Einwendung des anrainenden Betriebsinhabers, dass er "ein rechtliches Interesse daran (hat), dass durch faktisches Heranrücken
von als Wohnungen genützten Objekten an seine Betriebsanlage seine gewerberechtlichen Befugnisse nicht (zus?tzlich) beeintr?chtigt
werden", stellt keine Einwendung im Rechtssinne dar, weil daraus nicht zu erkennen ist, in welchem geschützten subjektiv-?ffentlichen
Recht sich der Nachbar durch die beabsichtigte Bauführung für verletzt erachtet. 相似文献
997.
Peng Jiang Liang Chang Fangya Pan Hongyu Jia Zhilin Chen Shanqing Liang 《应用聚合物科学杂志》2024,141(5):e54886
A tetrakis (melamine)-1-hydroxyethylidene-1,1-diphosphonic acid salt (EA-MEL) was synthesized by a straightforward acid–base neutralization reaction between 1-hydroxyethylidene-1,1-diphosphonic acid (EA) and melamine (MEL). This compound, which contains phosphorus and nitrogen elements, exhibits a 40% carbon residue at a temperature of 800°C. When combined with diethyl aluminium hypophosphite (OP1230) as a flame-retardant composite in polylactic acid (PLA)/polyamide 11 blends through melt blending, a synergistic effect between the two flame retardants is observed. Consequently, the limiting oxygen index value significantly increases to 34.3, showcasing a remarkable 64.6% improvement. Additionally, the material achieves a V-0 rating according to UL-94 standards, and the peak heat release rate drops to 269 kW∙m−2 with the addition of just 5 wt% EA–MEL. These results demonstrate that EA-MEL and OP1230 contribute to the generation of phosphoric acid derivatives and the formation of a crosslinked ( P N )n or ( P O N )n network. This network enables the formation of a complete, compact, and expanded char residue, effectively isolating heat and oxygen. 相似文献
998.
Ananías Pascoal Marta Prado Pilar Calo Alberto Cepeda Jorge Barros-Velázquez 《European Food Research and Technology》2005,220(3-4):444-450
The identification of beef in animal foods is a major concern not only for the prevention of commercial fraud, but also to avoid safety risks deriving from the presence of prohibited bovine material that might be harmful to both human and animal health. Here we report a novel set of bovine-specific primers, CYTbos1 (forward) and CYTbos2 (reverse), which allow the specific amplification of a 115 base pair fragment of the bovine cytochrome b gene (cytb) between nt 844 (mitochondrial site 15,590) and nt 958 (mitochondrial site 15,704), no cross-reaction being observed with DNA from another 12 frequent commercial meat species. The polymerase chain reaction product obtained is cleaved specifically by endonucleases ScaI and TspE1 to achieve further confirmation evidence. The sensitivity of the proposed method was 0.025%. The CYTbos primers successfully detected bovine DNA in meat samples processed for 20 min at 133 °C/300 kPa or for 2 h at 121 °C. CYTbos primers also detected bovine DNA in heat-processed commercial meat products exhibiting a complex nature, as well as in bovine specific risk materials. The proposed polymerase chain reaction method, aimed at detecting a small and specific fragment of the bovine mitochondrial DNA, may be especially useful for the direct identification of bovine DNA in foodstuffs subjected to severe heating under overpressure conditions. 相似文献
999.
Immobilized yeast cells extensively produced the diacetyl precursor, α-acetolactate, during alcohol fermentation. The activity of acetohydroxy acid synthetase, which is responsible for the formation of α-acetolactate from pyruvic acid, was high in cell-free extracts of immobilized yeast cells compared with that of free yeast cells. It was suggested that the expression of AHA synthase of immobilized yeast cells was increased during growth in the carrier as compared with free yeast cells. When the initial immobilizing yeast cell concentration was changed from 1.0 × 106 cells/ml to 1.0 × 109 cells/ml, production of α-acetolactate was reduced from 0.94 mg/l to 0.30 mg/l. Furthermore, during continuous fermentation for 10 d, the concentration of α-acetolactate in beer was 0.30 mg/l. 相似文献
1000.
Isaac Jardin Alejandro Berna-Erro Joel Nieto-Felipe Alvaro Macias Jose Sanchez-Collado Jose J. Lopez Gines M. Salido Juan A. Rosado 《International journal of molecular sciences》2022,23(23)
Orai1, the first identified member of the Orai protein family, is ubiquitously expressed in the animal kingdom. Orai1 was initially characterized as the channel responsible for the store-operated calcium entry (SOCE), a major mechanism that allows cytosolic calcium concentration increments upon receptor-mediated IP3 generation, which results in intracellular Ca2+ store depletion. Furthermore, current evidence supports that abnormal Orai1 expression or function underlies several disorders. Orai1 is, together with STIM1, the key element of SOCE, conducting the Ca2+ release-activated Ca2+ (CRAC) current and, in association with TRPC1, the store-operated Ca2+ (SOC) current. Additionally, Orai1 is involved in non-capacitative pathways, as the arachidonate-regulated or LTC4-regulated Ca2+ channel (ARC/LRC), store-independent Ca2+ influx activated by the secretory pathway Ca2+-ATPase (SPCA2) and the small conductance Ca2+-activated K+ channel 3 (SK3). Furthermore, Orai1 possesses two variants, Orai1α and Orai1β, the latter lacking 63 amino acids in the N-terminus as compared to the full-length Orai1α form, which confers distinct features to each variant. Here, we review the current knowledge about the differences between Orai1α and Orai1β, the implications of the Ca2+ signals triggered by each variant, and their downstream modulatory effect within the cell. 相似文献