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排序方式: 共有221条查询结果,搜索用时 187 毫秒
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目的制备双氯芬酸钠脉冲控释微丸并考察体外释放影响因素。方法采用挤出滚圆法制备载药丸芯,以水溶胀性材料低取代羟丙基纤维素为内包衣溶胀层,乙基纤维素水分散体为外包衣作为控释层制备脉冲控释微丸,并考察溶胀层材料类型、溶胀层和控释层包衣增重、介质pH值和微丸粒径等对药物释放的影响。结果药物通过控释层衣膜破裂释放,溶胀层材料类型、溶胀层和控释层包衣增重和微丸粒径等对脉冲控释微丸的释药时滞和释放速率均具有显著影响,药物释放情况不受介质pH值的影响。结论采用水溶胀性材料低取代羟丙基纤维素为内包衣层,制备的脉冲控释微丸,当内包衣层增重为11%和外包衣层增重胀层为17%时,达到了时滞为4h,时滞后1.5h累积释药80%以上的脉冲释药效果。 相似文献
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目的合成穿心莲内酯硝甲基衍生物.方法利用Michael加成反应机理,将硝甲基基团引入到穿心莲内酯的分子结构中,再对其进行一系列的酯化反应.结果合成了16个新的穿心莲内酯硝甲基衍生物,这些新化合物的分子结构经核磁共振谱、质谱等数据确证.结论化合物Ⅰ1~Ⅰ16显示出不同的抗肿瘤活性. 相似文献
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2-取代噻唑基苯并异硒唑-3(2H)-酮衍生物的合成及抗真菌活性 总被引:3,自引:0,他引:3
用2-氯硒基苯甲酰氯和2-氨基-4-芳基噻唑在DMF中闭环制得了9个2-取代噻唑基苯并异硒唑-3(2H)-酮衍生物,并对8种真菌的体外抑菌活性进行测试.结果表明此类化合物对常见深部致病真菌,如白念珠菌、新生隐球菌、申克氏孢子丝菌等有一定的体外抑制活性,其中化合物2和3对新生隐球菌的活性分别是对照药氟康唑的4倍和2倍,化合物3和9对裴氏着色真菌的活性均是对照药氟康唑和布替萘芬的2倍. 相似文献
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《Drug testing and analysis》2017,9(5):778-787
This article reports on the analytical properties of five pyrrolidinyl substituted cathinones: α ‐pyrrolidinononaphenone (α ‐PNP, 1 ), 4‐chloro‐α ‐pyrrolidinopropiophenone (4‐Cl‐α ‐PPP, 2 ), 4‐chloro‐α ‐pyrrolidinovalerophenone (4‐Cl‐α ‐PVP, 3 ), 5‐dihydrobenzofuranpyrovalerone (5‐DBFPV, 4 ), and 2‐(pyrrolidin‐1‐yl)‐1‐(5,6,7,8‐tetrahydronaphthalen‐2‐yl)hexan‐1‐one (β ‐THNPH, 5 ). These identifications were based on liquid chromatography–quadrupole time‐of‐flight‐mass spectrometry (LC–QTOF–MS), gas chromatography–mass spectrometry (GC–MS) and nuclear magnetic resonance spectroscopy (NMR). To our knowledge, no analytical data about α ‐PNP, 4‐Cl‐α ‐PPP, 4‐Cl‐α ‐PVP, and β ‐THNPH have appeared until now, making this the first report on these compounds. Moreover, in order to study the collision‐induced dissociation (CID) characteristic fragmentation routes of pyrrolidinyl substituted cathinones, a total number of 13 pyrrolidinyl substituted cathinones were selected and discussed. The major fragmentation pathways under CID mode are produced, leading to the formation of characteristic ions. Product ions of [M‐C4H9N]+ and CnH2nN+ indicate the presence of pyrrolidinyl substitution. Characteristic fragments are also produced via the cleavages of the CH–N(CH2)4 bond and the CO‐CHN bond. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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《Expert opinion on therapeutic patents》2013,23(2):203-213
Introduction: Secondary and tertiary sulfonamides (R-SO2NR1R2) are defined by the single or double N-alkyl or N-aryl/heteroaryl substitution of the primary sulfonamide respectively. They can be obtained easily by the classical SN2 or nucleophile acyl substitution displacements using the appropriate synthones. Many classes of compounds used in therapy present the substituted sulfonamide groups and there is also a continuous interest in different fields such as the herbicides herein schematically reported. Areas covered: The intent of this article is to give a comprehensive overview of the most important patents in the last decade related to pathologies of great interest. All selected patents claim new compounds bearing the secondary or/and tertiary sulfonamide moiety, and state to have biological activities. The article is neither intended for detailed discussions of the sulfonamides mode of action on the specific therapeutic targets, nor for their contribution to the physicochemical properties of the molecules they are introduced into, as the scientific literature in such topics is exhaustive and in many cases, debates are still ongoing. The main fields covered are related to pathologies affecting the CNS, cardiac disorders, anti-virals, inflammation diseases, glaucoma, bone remodeling, anti-cancer, and finally a section is also dedicated to herbicides. Expert opinion: The insertion of the secondary/tertiary sulfonamide group into the organic scaffolds is chemically straightforward and not associated to particular toxicity in the cells or in the organisms. Therefore, it is possible to create large libraries of compounds, which can be tested for different diseases. As demonstrated by the patents reported in the present review, the research in medicinal chemistry, and other fields, takes big advantages as new leads are created, and might be further developed. 相似文献
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Termination of Living Anionic Polymerization of Butyl Acrylate with α‐(Chloromethyl)acrylate for End‐Functionalization and Application to the Evaluation of Monomer Reactivity 下载免费PDF全文
Yasuhiro Kohsaka Shoya Ishihara Tatsuki Kitayama 《Macromolecular chemistry and physics.》2015,216(14):1534-1539
Anionic polymerization of n‐butyl acrylate (nBA) in toluene initiated with a binary initiator, isopropyl α‐lithioisobutyrate/ethylaluminum bis(2,6‐di‐tert‐butylphenoxide) at ?60 °C, is terminated with ethyl α‐(chloromethyl)acrylate (ECMA) to afford a poly(nBA) possessing an acryloyl group at the terminal with 80% of termination efficiency. The reactivity of nBA against a polymer anion of methyl methacrylate formed under identical conditions is estimated relative to the termination with ECMA by reacting a mixture of nBA and ECMA followed by 1H NMR spectroscopic chain‐end analysis; the relative reactivity of nBA is found 80 times or more higher than ECMA.
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Brian Cox James Duffy Victor Zdorichenko Corentin Bellanger Jessica Hurcum Benoît Laleu Kevin I. Booker-Milburn Luke D. Elliott Michael Robertson-Ralph Christopher J. Swain Stephen J. Bishop Irene Hallyburton Mark Anderson 《ACS medicinal chemistry letters》2020,11(12):2497
We utilized synthetic photochemistry to generate novel sp3-rich scaffolds and report the design, synthesis, and biological testing of a diverse series of amides based on the 1-(amino-methyl)-2-benzyl-2-aza-bicyclo[2.1.1]hexane scaffold. Preliminary antimalarial screening of the library provided promising compounds with activity in the 1–5 μM range with an enhanced hit rate. Further evaluation (solubility, drug metabolism and pharmacokinetics (DMPK), and toxicity) of a selected compound (9) suggested that this series represents an excellent opportunity for further optimization with the framework offering multiple opportunities for the addition of uniquely vectorally positioned extra functionality. 相似文献
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To identify new agents for the treatment of American cutaneous leishmaniasis, a series of eight 1,4‐bis(substituted benzalhydrazino)phthalazines was evaluated against Leishmania braziliensis and Leishmania mexicana parasites. These compounds represent a disubstituted version of the 1‐chloro‐4‐(monoaryl/heteroarylhydranizyl)phthalazine that exhibited a significant response against L. braziliensis according to our previous findings. Two disubstituted phthalazines 3b and 3f were identified as potential antileishmanial agents against L. braziliensis parasites, exhibiting a submicromolar IC50 response of 2.37 and 7.90 µM on the promastigote form, and of 1.82 and 4.56 µM against intracellular amastigotes, respectively. In particular, compound 3b showed interesting responses against amastigote isolates from reference, glucantime‐resistant and clinical human strains, which were by far superior to the biological response found for the glucantime drug. With regard to the toxicity results, both 3b and 3f exhibited moderate LD50 values against murine macrophages (BMDM), with good selectivity indexes on promastigotes and intracellular amastigotes of L. braziliensis. A comparison of biological response was established between the monosubstituted and disubstituted versions of these benzalhydrazino‐phthalazines. Easy synthetic procedure and significant response against amastigote strains including against resistant lines made compound 3b a potential candidate for further pharmacokinetic and in vivo experiments as antileishmanial agent, and as a platform for further structural optimization. Mechanism‐of‐action studies and molecular docking simulations discarded to inhibition of superoxide dismutase as possible mode of action. 相似文献