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101.
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Aldo Balsamo Bruno Macchia Franco Macchia Armando Rossello Paolo Domiano 《Tetrahedron letters》1985,26(34):4141-4144
The reaction of 4-iodomethylazetidin-2-one (2) with the t-butyl ester of propiolic acid (4) in the presence both of equimolar amounts of copper(I) and oxygen results unexpectedly in the fomation of the β-lactam ynamide 5. Its structure was suggested by spectroscopic data and confirmed by single-crystal X-ray analysis. 相似文献
104.
The relative configuration of diastereomeric cyclonona-2,3-diene-1-ols, (1RS,aRS)2, and (1RS,aSR), was determined by chemical methods, and confirmed by X-ray analysis of the phenylurethane derivative of the (1RS,aRS) isomer, 3a. 相似文献
105.
Daniela A. Bocchini Valquiria B. Damiano Eleni Gomes Roberto Da Silva 《Applied biochemistry and biotechnology》2003,106(1-3):393-401
The alkalophilic Bacillus circulans D1 was isolated from decayed wood. It produced high levels of extracellular cellulase-free xylanase. The enzyme was thermally
stable up to 60°C, with an optimal hydrolysis temperature of 70°C. It was stable over a wide pH range (5.5—10.5), with an
optimum pH at 5.5 and 80% of its activity at pH 9.0. This cellulase-free xylanase preparation was used to biobleach kraft
pulp. Enzymatic treatment of kraft pulp decreased chlorine dioxide use by 23 and 37% to obtain the same kappa number (κ number)
and brightness, respectively. Separation on Sephadex G-50 isolated three fractions with xylanase activity with distinct molecular
weights. 相似文献
106.
107.
Benjamin Guieu Cedric Lecoutey Rmi Legay Audrey Davis Jana Sopkova de Oliveira Santos Cosimo Damiano Altomare Marco Catto Christophe Rochais Patrick Dallemagne 《Molecules (Basel, Switzerland)》2021,26(1)
Alzheimer’s disease (AD) is a multifactorial neurodegenerative disease towards which pleiotropic approach using Multi-Target Directed Ligands is nowadays recognized as probably convenient. Among the numerous targets which are today validated against AD, acetylcholinesterase (ACh) and Monoamine Oxidase-B (MAO-B) appear as particularly convincing, especially if displayed by a sole agent such as ladostigil, currently in clinical trial in AD. Considering these results, we wanted to take benefit of the structural analogy lying in donepezil (DPZ) and rasagiline, two indane derivatives marketed as AChE and MAO-B inhibitors, respectively, and to propose the synthesis and the preliminary in vitro biological characterization of a structural compromise between these two compounds, we called propargylaminodonepezil (PADPZ). The synthesis of racemic trans PADPZ was achieved and its biological evaluation established its inhibitory activities towards both (h)AChE (IC50 = 0.4 µM) and (h)MAO-B (IC50 = 6.4 µM). 相似文献
108.
Damiano Librizzi Nicole Cabanel Maxim Zavorotnyy Elisabeth Riehl Tilo Kircher Markus Luster Behrooz Hooshyar Yousefi 《Molecules (Basel, Switzerland)》2021,26(5)
PET of β-Amyloid plaques (Aβ) using [18F]florbetaben ([18F]FBB) and [18F]fluorodeoxyglucose ([18F]FDG) increasingly aid clinicians in early diagnosis of dementia, including Alzheimer’s disease (AD), frontotemporal disease, dementia with Lewy bodies, and vascular dementia. The aim of this retrospective analysis was to evaluate clinical relevance of [18F]FBB, [18F]FDG PET and complimentary CSF measurements in patients with suspected dementia. In this study, 40 patients with clinically suspected or history of dementia underwent (1) measurement of Aβ peptides, total tau, and p-tau protein levels in the cerebrospinal fluid (CSF) compared with healthy controls (HC); (2) clinical and neuropsychological assessment, which included Consortium to Establish a Registry for Alzheimer’s Disease neuropsychological assessment battery (CERAD-NAB); (3) [18F]FBB and [18F]FDG PET imaging within an average of 3 weeks. The subjects were within 15 days stratified using PET, CSF measurements as HC, mild cognitive impaired (MCI) and dementia including Alzheimer´s disease. The predictive dementia-related cognitive decline values were supporting the measurements. PET images were evaluated visually and quantitatively using standard uptake value ratios (SUVR). Twenty-one (52.5%) subjects were amyloid-positive (Aβ+), with a median neocortical SUVR of 1.80 for AD versus 1.20 relative to the respective 19 (47.5 %) amyloid-negative (Aβ-) subjects. Moreover, the [18F]FDG and [18F]FBB confirmed within a sub-group of 10 patients a good complimentary role by correlation between amyloid pathology and brain glucose metabolism in 8 out of 10 subjects. The results suggest the clinical relevance for [18F]FBB combined with [18F]FDG PET retention and CFS measurements serving the management of our patients with dementia. Therefore, [18F]FBB combined with [18F]FDG PET is a helpful tool for differential diagnosis, and supports the patients’ management as well as treatment. 相似文献
109.
Photochemical transformations of pyridinium salts: mechanistic studies and applications in synthesis
The discovery, understanding and synthetic exploitation of the photochemical transformation of pyridinium salts are described. The investigations surrounding the remarkable transformation of pyridinium salts into a host of structurally complex motifs have helped extend the comprehension of aromatic and heteroaromatic photochemistry. The synthetic community has, in recent years, recognised the potential inherent in these compounds and has since exploited the irradiation of variously substituted pyridinium salts as key steps in the preparation of advanced intermediates in numerous synthetic programmes. 相似文献
110.
Tuccinardi T Ortore G Rossello A Supuran CT Martinelli A 《Journal of chemical information and modeling》2007,47(6):2253-2262
Carbonic anhydrase (CA) IX is a very interesting subject for study due to its overexpression in cancer and its expression in very few normal tissues. There are not yet experimental 3D structures of the catalytic domain of this isozyme, and only a few computational studies have been reported. A homology model of CA IX was developed, and using Gold software 124 CA IX inhibitors were docked. The best poses of the ligands were then used as an alignment tool for the development of the first reported CA IX 3D-QSAR model. The obtained results confirm the reliability of the constructed CA IX model and the proposed computational strategy for investigating CAs. 相似文献