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1.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts
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以3,4-二甲基苯胺为原料,合成了4,5-二甲基-1,2-二苯胺,产品收率达69%以上。在乙酰化、硝化反应中引入了1,2-二氯乙烷溶剂。用正交实验确定了最佳原料配比:n(3,4-二甲基苯胺)∶n(醋酸酐)∶n(硫酸)=1.00∶1.15∶1.10,硝化反应温度为13°C,反应时间为3.5h,硝化产物收率为90.56%,溶剂回收率95%以上。改进后,每摩尔母体的醋酸酐用量由303g减少至118g,浓硫酸用量由304g减少至108g。 相似文献
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以对氨基苯磺酸为起始原料 ,经过乙酰化、硝化、水解三步来制备标题物。通过正交试验找出了酰化的最佳反应条件为 :对氨基苯磺酸与乙酐的摩尔比为 1∶1.0 5 ,反应总时间为 1.5h ,反应温度为 2 5℃ ,酰化介质为酰化反应前用碳酸钠及水将对氨基苯磺酸完全溶解 ,使混合液 pH值为 5~ 6 ,反应过程中不再补加碳酸钠 ,其酰化转化率可达 99.6 % ,酰化产物的固体收率可达 96 .0 % ;硝化反应的最佳条件为 :硝化剂用 90 .2 %的硝酸 ,对乙酰氨基苯磺酸与硝化剂的摩尔比为 1∶1.0 5 ,反应温度为 10℃ ,浓硫酸与对乙酰氨基苯磺酸的摩尔比为 8.3∶1,其硝化转化率可达 96 .0 % ,硝化反应的选择性好 ,对氨基邻硝基苯磺酸的量不到 1.0 %。 相似文献
6.
在四氯化碳中合成邻硝基对甲基苯胺的研究 总被引:3,自引:0,他引:3
以对甲基苯胺为母体,合成了邻硝基对甲苯胺,产品收率在85%以上,在乙酰化,硝化反应中引入了四氯化碳溶剂,2最佳原料配比为对甲基苯胺;醋酐:硫酸=1:1.30:1.13。改进后,每mol母体的醋酐用量由3.10mol减少至1.30mol,浓硫酸用量由3.17mol减少至1.13mol,溶剂回收率在95%以上。 相似文献
7.
Colussi C Banfi C Brioschi M Tremoli E Straino S Spallotta F Mai A Rotili D Capogrossi MC Gaetano C 《Proteomics. Clinical applications》2010,4(1):71-83
Purpose: Histone Deacetylase Inhibitors (DI) ameliorates dystrophic muscle regeneration restoring muscular strength in the mdx mouse model of Duchenne muscular dystrophy (DMD). The further development of these compounds as drugs for DMD treatment is currently hampered by the lack of knowledge about DIs effect in large dystrophic animal models and that of suitable biomarkers to monitor their efficacy. Experimental design: In this study we applied proteomic analysis to identify differentially expressed proteins present in plasma samples from mdx mice treated with the Suberoylanilide hydroxamic acid (SAHA) and relative normal controls (WT). Results: Several differentially expressed proteins were identified between untreated wild type and mdx mice. Among these, fibrinogen, epidermal growth factor 2 receptor, major urinary protein and glutathione peroxidase 3 (GPX3) were constitutively up‐regulated in mdx, while complement C3, complement C6, gelsolin, leukaemia inhibitory factor receptor (LIFr), and alpha 2 macroglobulin were down‐regulated compared to WT mice. SAHA determined the normalization of LIFr and GPX3 protein level while apoliprotein E was de novo up‐regulated in comparison to vehicle‐treated mdx mice. Conclusions and clinical relevance: Collectively, these data unravel potential serological disease biomarkers of mdx that could be useful to monitor muscular dystrophy response to DI treatment. 相似文献
8.
Mariam Markouli Dimitrios Strepkos Christina Piperi 《International journal of molecular sciences》2022,23(21)
Hematologic malignancies are a large and heterogeneous group of neoplasms characterized by complex pathogenetic mechanisms. The abnormal regulation of epigenetic mechanisms and specifically, histone modifications, has been demonstrated to play a central role in hematological cancer pathogenesis and progression. A variety of epigenetic enzymes that affect the state of histones have been detected as deregulated, being either over- or underexpressed, which induces changes in chromatin compaction and, subsequently, affects gene expression. Recent advances in the field of epigenetics have revealed novel therapeutic targets, with many epigenetic drugs being investigated in clinical trials. The present review focuses on the biological impact of histone modifications in the pathogenesis of hematologic malignancies, describing a wide range of therapeutic agents that have been discovered to target these alterations and are currently under investigation in clinical trials. 相似文献
9.
Huimin Zhang Le Xie Sen Chen Yue Qiu Yu Sun Weijia Kong 《International journal of molecular sciences》2022,23(21)
Different serum thyroxine levels may influence the morphology of the inner ear during development. A well-developed organ of Corti (OC) is considered to be critical to the function of hearing. In our study, we treated mice with triiodothyronine (T3) and found that the opening of the OC occurred sooner than in control mice. We also observed an increased formation of acetylated microtubules and a decrease in the adhesion junction molecule P-cadherin the during opening of the OC. Our investigation indicates that thyroxin affects P-cadherin expression and microtubule acetylation to influence the opening of the OC. 相似文献
10.
以竹材为原料制备出醋化级的竹浆粕。采用FT-IR、X-ray以及HPLC对竹浆粕的物理化学性质进行了表征,开展了以竹浆粕为原料的醋化反应实验,并与木浆进行了比较。研究结果表明,竹浆粕中的α-纤维的含量能够满足醋化级浆粕的要求,并且由于其中纤维素的结晶度低,竹浆粕的醋化反应活性比木浆粕更高。以竹浆粕为原料合成的醋酸纤维素在丙酮中具有与木浆醋片相似的溶解性能。开发以竹材为原料制备竹浆,合成醋酸纤维素的工艺是完全可行的。 相似文献