酸敏感型嵌段共聚物mPEG-acetal-PIB的合成、表征及用于构筑水凝胶敷料

利用点击化学(“Click”)反应, 成功制备了一种通过酸敏感缩醛基团键合的两亲性嵌段共聚物, 聚乙二醇单甲醚-acetal-聚异丁烯(简写为mPEG-acetal-PIB). 通过核磁共振氢谱(¹H NMR)、红外光谱(FT-IR)和凝胶渗透色谱(GPC)对聚合物的结构、分子量及分子量分布进行表征. 利用芘荧光探针法、动态激光光散射(DLS)和透射电子显微镜(TEM), 研究共聚物在水溶液中组装的临界聚集浓度(CAC), 胶束的粒径大小、分布以及形貌. 利用DLS跟踪测试聚合物胶束在酸性条件下的粒径变化, 验证mPEG-acetal-PIB的酸敏感性质. 随后, 在体系中引入α-环糊精(α-CD), 诱导形成超分子水凝胶. 利用X射线衍射(XRD)分析PEG与α-CD的包结络合作用, 流变仪测试水凝胶的凝胶化时间和黏弹性. 通过体外细胞毒性试验(MTT法)证明嵌段共聚物mPEG-acetal-PIB及水凝胶均具有良好的生物相容性. 这种水凝胶能够保持创面湿润, 具有温和的冷却作用, 并且由于其带有酸敏感基团, 能够在偏酸性环境降解, 减少炎症发生率, 在水凝胶创伤敷料中具有潜在的应用.     

二杂芳基乙烯光二聚反应与二聚体的晶体结构

通过反-1,2-双(2-苯并唑基)乙烯(BBE)和反-1-(2-苯并咪唑基)-2-(2-苯并唑基)乙烯(BME)的光二聚反应合成了r-1,c-2,t-3,t-4-四(2-苯并唑基)环丁烷(BBC)和r-1,c-2,t-3,t-4-1,3-双(2-苯并咪唑基)-2,4-双(2-苯并唑基)环丁烷(BMC).用元素分析、红外、紫外、核磁共振谱、质谱及X射线衍射表征了二聚体的结构.BBC晶体属三斜晶系,空间群为P1.晶胞参数:a=0.64684(13)nm,b=1.3242(3)nm,c=1.6245(3)nm;α=74.66(3)°,β=78.77(3)°,γ=76.06(3)°,Z=2.BBC晶胞中分子有两种取向,两种取向不同分子的苯并唑平面间存在着π-堆积现象.π-堆积面间的距离在0.330～0.376nm之间,与石墨晶体中分子平面片层间的距离非常接近.BBC和BMC都具有中心对称性,光二聚反应的高度立体选择性以及BBE和BME的光二聚反应不受空气中氧的影响的事实表明它们是经激发单线态历程以面对面的方式进行二聚反应的,本文检测到了BBE和BME在高浓度溶液中的激基缔合物荧光.     

Molecular and Supramolecular Structures of Triiodides and Polyiodobismuthates of Phenylenediammonium and Its N,N-dimethyl Derivative

Despite remarkable progress in photoconversion efficiency, the toxicity of lead-based hybrid perovskites remains an important issue hindering their applications in consumer optoelectronic devices, such as solar cells, LED displays, and photodetectors. For that reason, lead-free metal halide complexes have attracted great attention as alternative optoelectronic materials. In this work, we demonstrate that reactions of two aromatic diamines with iodine in hydroiodic acid produced phenylenediammonium (PDA) and N,N-dimethyl-phenylenediammonium (DMPDA) triiodides, PDA(I₃)₂⋅2H₂O and DMPDA(I₃)I, respectively. If the source of bismuth was added, they were converted into previously reported PDA(BiI₄)₂⋅I₂ and new (DMPDA)₂(BiI₆)(I₃)⋅2H₂O, having band gaps of 1.45 and 1.7 eV, respectively, which are in the optimal range for efficient solar light absorbers. All four compounds presented organic–inorganic hybrids, whose supramolecular structures were based on a variety of intermolecular forces, including (N)H⋅⋅⋅I and (N)H⋅⋅⋅O hydrogen bonds as well as I⋅⋅⋅I secondary and weak interactions. Details of their molecular and supramolecular structures are discussed based on single-crystal X-ray diffraction data, thermal analysis, and Raman and optical spectroscopy.     

Synthesis and Applications of Carbohydrate-Based Organocatalysts

Organocatalysis is a very useful tool for the asymmetric synthesis of biologically or pharmacologically active compounds because it avoids the use of noxious metals, which are difficult to eliminate from the target products. Moreover, in many cases, the organocatalysed reactions can be performed in benign solvents and do not require anhydrous conditions. It is well-known that most of the above-mentioned reactions are promoted by a simple aminoacid, l-proline, or, to a lesser extent, by the more complex cinchona alkaloids. However, during the past three decades, other enantiopure natural compounds, the carbohydrates, have been employed as organocatalysts. In the present exhaustive review, the detailed preparation of all the sugar-based organocatalysts as well as their catalytic properties are described.     

Investigation of Inclusion Complexes Between α-Cyclodextrin and Ferrocene by ESI-MSn and Cyclic Voltammetry

The inclusion complexes of α-cyclodextrin (α-CD) and FcCO2 (CH2)18(FcSH) and their self-as-sembled monolayers (SAMs) on gold surface were investigated by electrospray tandem ionization mass spectrometry (ESI-MS″) and cyclic voltammetry, respectively. The interfacial electrochemical response of the SAMs is related to the way in which the inclusion complexes formed.     

新型桃金娘烯醛基双酰胺-噻二唑化合物的合成及其抗真菌活性

以α-蒎烯为起始原料,经氧化制得桃金娘烯酸（3）;脂肪族二酸在POCl₃作用下与氨基硫脲经脱水环合制得脂肪族双噻二唑（4a~4h）; 4a~4h分别与3经脱水反应合成了8个新型的桃金娘烯醛基双酰胺噻二唑化合物（5a~5h）,其结构经¹H NMR, ¹³C NMR, IR和ESI-MS表征。抗真菌活性测试结果表明,在用药量为50 μg·mL^-1时,5a~5h对黄瓜枯萎病菌、花生褐斑病菌、苹果轮纹病菌、番茄早疫病菌和小麦赤霉病菌均有一定的抑制作用,其中桃金娘烯醛-辛二酸基双酰胺-噻二唑(5f)对苹果轮纹病菌的抑制率为60.3%,桃金娘烯醛-丁二酸基双酰胺-噻二唑(5b)和桃金娘烯醛-癸二酸基双酰胺-噻二唑(5h)对小麦赤霉病菌的抑制率分别为52.8%和54.4%。     

光学活性噻吗洛尔的合成

噻呜洛尔(Timolol)是一种新型的β-受体阻断剂。化学名为S-(-)-1-叔丁胺基-3-[(4-吗啉代-1,2,5-噻二唑-3-基)氧]-2-丙醇顺丁烯二酸盐。     

N-(5-芳苄叉基饶丹宁)左氧氟沙星酰胺的合成及抗肿瘤活性

为进一步发现氟喹诺酮药物向抗肿瘤活性转化的结构修饰新策略,用酰氨基为左氧氟沙星(1)C-3羧基的电子等排体,5-芳苄叉基饶丹宁为其功能修饰基,设计合成了N-(5-芳苄叉基饶丹宁)左氧氟沙星酰胺类目标化合物(6a-6n)。 体外抗肿瘤活性结果表明,所合成的14个化合物的活性均强于母体左氧氟沙星,且对正常细胞表现出较低的细胞毒性作用。 构效关系表明,增大芳基取代基的体积或供电性均导致抗肿瘤活性的明显降低,反之,吸电子取代苯基或芳香杂环类目标化合物的抗肿瘤活性强于其他取代基类。 其中,硝基化合物6l、呋喃6m和吡啶6n对人胰腺癌细胞株(Capan-1)的半数抑制浓度(IC₅₀) 与对照抗肿瘤药阿霉素(1.6 μmol/L)相当,分别为1.8、0.8和1.3 μmol/L。 因此,芳苄叉基饶丹宁修饰的酰氨基替代C-3羧基有利于提高氟喹诺酮的抗肿瘤活性。     

Synthesis and thermal decomposition of cobalt-containing oligosilanes

Oligo(phenylcobaltcarbonylsilane) was prepared from oligo(phenylsilane) and dicobalt octacarbonyl. The reaction proceeds with elimination of H₂ and CO and insertion of cobalt carbonyl fragments into the silicone backbone of oligosilane. Oligosilane containing cobalt carbonyl groups in side organic substituents was obtained from oligolmethyl(phenylethynyl)Isilane and CO₂(CO)₈. The reaction of 1,2-bis(phenylethyny1)tetramethyldisilane with Co₂(CO)₈ proceeds with the sequential attachment of cobalt carbonyl fragments to ethynyl groups to form disilane derivatives [²-CCPhCo₂(CO)₆] Thermal decomposition of cobalt-containing oligosilanes affords a mixture of paramagnets and ferromagnets.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya. No. 10, pp. 2561–2567, October, 1996.     

Gold-catalyzed Intermolecular Oxidation of Phenylacetylene and Allylic Sulfides: an Efficient and Practical Synthesis of α-Phenylthio Ketone

An efficient and practical synthesis of α-phenylthio ketone through gold-catalyzed intermolecular oxidation of phenylacetylene and substituted aryl(benzyl) allylic sulfides was developed. The reaction scope is fairly good with substituted aryl(benzyl) allylic sulfides, tolerating various functional groups, and the reaction affords the yields of 63%—85%.     

Phytochemical Profile and Antioxidant Activities of Coleus amboinicus Lour. Cultivated in Indonesia and Poland

Coleus amboinicus Lour., Lamiaceae, is a perennial herb that is native to Indonesia and also cultivated in Africa, Asia and Australia. The major phytochemicals responsible for its bioactivity are rosmarinic acid (RA) and its analogues, flavonoids and abietane diterpenoids. The possibility of cultivation in a colder climate would extend the use of this herb and provide new opportunities to herb growers and livestock farmers. Our study to compare feed value and phytochemical composition of C. amboinicus plants cultivated in its original region, Indonesia, and in Poland. The crude protein content was significantly higher in plants cultivated in Indonesia compared to those cultivated in Poland—21% and 13% of dry matter, respectively. The higher ADF contents were detected in C. amboinicus cultivated in Indonesia, 38–41%, in comparison to 34% in plants cultivated in Poland. The phytochemical composition was also significantly influenced by the cultivation location. Polish samples were higher in polyphenols (RA and its analogues), and also had 1.5–2-fold higher antioxidant potential, as measured by DPPH scavenging, phosphomolybdenum reduction and Fenton reaction driven lipid peroxidation. The Indonesian samples contained more diterpenoid compounds, such as dihydroxyroyleanone, and the sum of terpenoids was ca. 10 times higher than in samples from Poland (15.59–23.64 vs. 1.87 µg/g of extracts). In conclusion, C. amboinicus is suitable for cultivation in non-optimal climatic conditions but some nutritional properties and bioactivity are significantly affected.     

Combined study of thermochemical properties of nitroform and its salts

A combined method for determination of the standard enthalpies of formation of nitroform and its salts was proposed. The enthalpies of dissolution of nitroform and its ammonium, hydrazinium, guanidinium, and potassium salts in water were measured. The enthalpy of combustion of hydrazinium salt of nitroform was determined by a combustion calorimetry, and its standard enthalpy of formation was calculated. The enthalpy of formation of trinitromethyl anion in indefinitely diluted aqueous solution −24.94±0.79 kJ mol⁻¹, was calculated on the basic of the data obtained for enthalpies of formation and dissolution of ammonium and hydrazinium salts of nitroform. Standard enthalpies of formation of nitroform and its salts were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2451–2454, December, 1998.     

大气颗粒物中砷及其形态的研究进展

大气颗粒物中毒性准金属元素砷及其形态含量变化引起的环境健康问题受到了广泛关注。由于工业生产和煤燃烧等人类活动,砷普遍存在于多种环境介质中。排放到大气中的砷能够随气流进行长距离迁移,致使一些偏远区域大气中的砷含量明显超出欧盟的限制标准(6 ng/m3)。砷的毒性表达很大程度依赖其存在种态,无机砷毒性大于有机砷,且砷(Ⅲ)的毒性明显强于砷(Ⅴ)。本文概述了大气中砷的来源,并选取自2000年来的代表性成果比较了不同国家及不同功能区大气砷的含量变化,同时对1975年来多数关于大气颗粒物中砷形态变化特征的研究进行了评述。     

化学专业概论教学中的课程思政探索与实践*——以华中科技大学“一院一品”化学专业概论课为例

课程思政是高校落实立德树人根本任务的重要举措,是完善“三全育人”的重要抓手。化学是我国科学研究的重要基础,对提升原始创新能力具有重要意义。化学专业教学中融入思想政治教育的前提是建设好一门课程。针对当前专业课教学中存在的课程思政体系不完善、思政元素与专业课程融合程度低、教师思政教学水平有待提高等问题,以华中科技大学化学与化工学院专业概论课为试点,完善课程设计与教学方法,探索化学专业教学中的课程思政建设。通过剖析化学课程思政的意义与难点,构建专业概论课实施方案,形成一套行之有效的化学课程思政建设体系。     

基于DNA分子的纳米功能材料的设计、组装及应用

DNA除了作为一种遗传信息的载体分子之外,还可以通过折叠或组装从而形成特定的二维和三维结构。通过设计DNA分子的结构并探索其与纳米材料之间的相互作用的研究已经引起了国内外学术界的持续关注。DNA功能化的无机纳米材料促进了分析科学、生命科学以及环境科学的快速发展。本文将从疾病分子机制研究、疾病诊断和疾病治疗三个角度出发,探究面向生物医学分析应用的DNA分子功能化的无机纳米材料的设计与组装。除此之外,还对DNA功能化纳米材料技术的发展前景进行了展望。     

新型茼蒿素类似物的合成和抗虫构效关系研究

Twenty-one tonghaosu analogs were synthesized via hydroamination or selective reduction of the endocyclic double bond of the corresponding dienol spiroketals. Structures of all the new compounds were confirmed by ^1H NMR, IR, MS, HREIMS or elemental analysis. Their antifeedant activity against large white butterfly （Pieris brassicae L） and larvicidal activity toward mosquito （Culex quinquefasciatus Say） were examined. Some of them exhibited antifeeding activities comparable to or stronger than tonghaosu Z-1. Based on the activity data, the preliminary structure-activity relationship was also discussed, which might be instructive for finding out lead compounds with better bioactivities in the future.     

化学本科基础教育中教学内容与指导观念改革的思考与探索

分析比较国内外本科化学专业基础教学的一些特点与利弊,提出从形式、内容及观念上进行国内化学教育探索与改革的可能方向,主要包括从题材上生动化,从内容上广度化,化学理论与现象相辅相成、和谐并重,在经验性总结中思辨等多个方面。从而逐渐改变目前高校化学基础教育中存在的教学模式死板,内容陈旧,评分体制单一,与生活脱轨,学生缺乏兴趣等相关问题。