Synthesis, Enzyme Localization, and Regulation of Neurosteroids
Sheryl S. Smith in Neurosteroid Effects in the Central Nervous System, 2003
In retrospect, Locock’s remarks provide initial clues that periodicity of seizures in epilepsy and the menstrual cycle may be linked via GABAA receptors, because it appears that bromides exert their anticonvulsant effects by permeating these receptors. Similar to many drugs known to act on GABAA receptors, bromides are sedatives. Bromides block seizures induced by the GABAA receptor antagonists pentylenetetrazol and picrotoxin. Bromides enhance the binding affinity of flunitrazepam and diazepam to GABAA receptors (Max, 1990). The bromide ion, like the chloride ion, is a monovalent anion that belongs to the halogen family. Bromide ions permeate the GABAA receptors more efficiently than chloride ions (Bormann et al., 1987). A recent detailed study demonstrated that bromides block seizures in the combined entorhinal cortex-hippocampal slice preparation and enhance paired pulse inhibition and GABA-mediated inhibitory postsynaptic currents (Meierkord
Bromides
Stanley R. Resor, Henn Kutt in The Medical Treatment of Epilepsy, 2020
At present it is not known how bromides act to prevent seizures, although there are several theories. As a halide, the bromide ion is handled similarly to chloride. Because its hydrated diameter is less than that of chloride it may pass through the membrane channels more readily and cause a hyperpolarization of the transmembrane potential, making neurons less likely to initiate a seizure discharge or to participate in the spread of the seizure (11). Other studies have shown that benzodiazepine binding is increased in the presence of bromides, suggesting that this ion may affect the function of the benzodiazepine/GABA ionophore (12). Other biochemical measures of GABA neurotransmission are not altered in the presence of bromide (13). It may also inhibit the action of carbonic anhydrase similarly to acetazolamide, which also has some antiepileptic activity (11).
Halogen Labeled Compounds (F, Br, At, Cl) *
Garimella V. S. Rayudu, Lelio G. Colombetti in Radiotracers for Medical Applications, 2019
The uses of radiolabeled pyrimidine analogs as potential diagnostic agents for tumor imaging have been discussed previously. Two radiobrominated analogs, 82Br-2- and 5-Bromo-2′-deoxyuridine were synthesized and their distribution and metabolism were studied in order to determine their utilities as tumor localization agents. No specific tumor localization with the 2-bromo analog was found in mice bearing subcutaneous Lewis Lung carcinoma. These results were attributed to rapid in vivo debromination as indicated by the similar distribution patterns with these analogs and 82Br-ammonium bromide.287, 288 In addition, 55% of the radioactivity from the 2-bromo analog was excreted as free bromide. It was concluded that these compounds could not be useful for tumor localization.287, 288
The discovery and development of aclidinium bromide for the treatment of chronic obstructive pulmonary disease
Published in Expert Opinion on Drug Discovery, 2018
Mario Malerba, Alessandro Radaeli, Giuseppe Santini, Jaymin Morjaria, Nadia Mores, Chiara Mondino, Giuseppe Macis, Paolo Montuschi
In comparison with other LAMAs, preclinical data suggest potential increased safety of aclidinium based on lower systemic exposure. In the rat pilocarpine-induced sialorrhea model, which is used for assessing the potential of investigational LAMAs to cause systemic side effects, aclidinium bromide, glycopyrronium bromide, and tiotropium bromide inhibited sialorrhea in a dose-dependent manner [41]. However, aclidinium bromide was 43- and 51-fold less potent than tiotropium bromide and glycopyrronium bromide, respectively, as reflected by their EC50 values [41]. This is likely due, at least partially, to more rapid hydrolysis of aclidinium bromide in rat, guinea pig, and human plasma compared to glycopyrronium bromide, tiotropium bromide, or ipratropium bromide [41]. Hydrolysis half-life of aclidinium in human plasma was reported to be 0.04 h [41].
Design, synthesis and biological evaluation of carbohydrate-based sulphonamide derivatives as topical antiglaucoma agents through selective inhibition of carbonic anhydrase II
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2020
Zhuang Hou, Chuanchao Li, Yichuang Liu, Miao Zhang, Yitong Wang, Zhanfang Fan, Chun Guo, Bin Lin, Yang Liu
The general synthetic strategy for the synthesis of the target compounds is shown in Scheme 1. Monosaccharide was selected as the starting material, and acetylation with acetic anhydride to form intermediate 2 in pyridine. The terminal glycosyl bromide 3 was prepared by the reaction of 2 with HBr-AcOH in good yield. Intermediate 4 was formed by the reaction of a glycosyl bromide with an excess of sodium azide. Next, the intermediate 4 was reacted with hydrogen under the catalysis of Pd/C to form an intermediate 5. The condensation reaction of amino sugar with p-sulphonamide benzoic acid forms an intermediate 6 with an amide bond as a linker. Finally, deacetylation with a catalytic amount of NaOCH3 in CH3OH gave the target analogue 720. All compounds were extensively characterised (Supplementary Material).
The effective photocatalysis and antibacterial properties of AgBr/Ag2MoO4@ZnO composites under visible light irradiation
Published in Biofouling, 2019
Huihui Xu, Jie Zhang, Xianzi Lv, Tianjie Niu, Yuxiang Zeng, Jizhou Duan, Baorong Hou
The SEM images of the 0.5 Ag2MoO4@ZnO and 0.5 AgBr/Ag2MoO4@ZnO samples are shown in Figure 3. This figure clearly shows that pure ZnO has a sheet structure with a thickness of ∼40 nm, while pure Ag2MoO4 has a spherical structure with a diameter of ∼2 μm. When adding a certain amount of sodium bromide during the preparation process, the diameter of Ag2MoO4 decreased to 80 nm. To some extent, the addition of sodium bromide can improve the specific surface area of the sample and provide more active sites for the degradation of organic pollutant in this catalysis system. In addition, SEM elemental mapping can describe the composition and distribution of the component elements. In Figure 3, different colors present elemental maps of Zn, O, Mo, Br, and Ag, and all five elements are uniformly distributed, which indicates that the composite catalysts were prepared successfully.
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