硝基苯并咪唑衍生物的合成、表征及抑茵活性的测定

以苯并咪唑为原料，经硝化、二茂铁磺酰化等步骤，合成了8种未见文献报道的硝基苯并咪唑衍生物，其结构经MS，^1H NMR和元素分析确证．由于硝基苯并咪唑的互变异构，二茂铁磺酰化后，产生两个异构体，用X射线衍射仪测定了化合物2a的晶体结构．初步的抑菌实验结果表明，该系列化合物具有良好的抑菌作用，其抑菌活性均优于对照药剂50％多菌灵可湿性粉剂．     

硝基苯并咪唑衍生物的合成、表征及抑菌活性的测定

以苯并咪唑为原料,经硝化、二茂铁磺酰化等步骤,合成了8种未见文献报道的硝基苯并咪唑衍生物,其结构经MS,¹H NMR和元素分析确证.由于硝基苯并咪唑的互变异构,二茂铁磺酰化后,产生两个异构体,用X射线衍射仪测定了化合物2a的晶体结构.初步的抑菌实验结果表明,该系列化合物具有良好的抑菌作用,其抑菌活性均优于对照药剂50%多菌灵可湿性粉剂.     

N-(酰基二茂铁)苯并咪唑类化合物的合成和表征

将二茂铁磺酰氯或二茂铁甲酰氯和1H-苯并咪唑衍生物反应,合成了12个未见文献报道的N-(酰基二茂铁)苯并咪唑类化合物,用IR、1HNMR、元素分析和MS对其结构进行了表征。结果表明,含有活泼氢的苯并咪唑衍生物能与二茂铁酰氯生成相应的N-(酰基二茂铁)苯并咪唑衍生物,并有较好的收率。     

甘氨酸衍生化β-环糊精键合硅胶液相色谱固定相的合成与评价

 β-环糊精键合硅胶经对甲苯磺酰化后,与甘氨酸反应得到甘氨酸衍生化β-环糊精键合硅胶固定相(GCDS)。考察了GCDS对位置异构体、丹磺酰化氨基酸异构体、苯丙酸类药物等的分离性能,研究了流动相中甲醇浓度、pH以及柱温对色谱保留行为的影响。     

1-二茂铁磺酰基-2-长链烷基苯并咪唑的合成、表征及晶体结构

二茂铁磺酰基苯并咪唑;合成;表征;晶体结构     

8—羟基喹啉衍生化β—环糊精键合硅胶液相色谱固定相的 …

β－环糊精键合硅胶经对甲苯磺酰化后,与８－羟基喹啉反应得到８－羟基喹啉衍生化β－环糊精键合硅胶固定相,采用元素分析,热分析及固体核磁波谱对键合相进行表征。考察了ＱＣＤＳ对位置异构体,丹磺酰化氨基酸异构体,苯丙酸类药物和核苷等的分离性能。     

8-羟基喹啉衍生化β-环糊精键合硅胶液相色谱固定相的合成与评价

β－环糊精键合硅胶经对甲苯磺酰化后, 与８－羟基喹啉反应得到８－羟基喹啉衍生化β－环糊精键合硅胶固定相（ＱＣＤＳ）． 采用元素分析、热分析及固体核磁波谱对键合固定相进行表征． 考察了ＱＣＤＳ对位置异构体、丹磺酰化氨基酸异构体、苯丙酸类药物和核苷等的分离性能．     

微波催化新型杂环基苯并咪唑杀菌剂的合成、表征及活性测定

以邻苯二胺及相应羧酸为原料,经环化、二茂铁磺酰化,合成了4种未见文献报道的二茂铁磺酰基苯并咪唑衍生物,经元素分析、MS、1H NMR测试技术确证结构。通过X射线衍射,测定了化合物4b的晶体结构,该晶体属单斜晶系,空间群P2(1)/c。晶胞参数:a=0.983 45(6)nm,b=1.702 37(11)nm,c=1.180 96(7)nm,α=90°,β=100.998(4)°,γ=90°,V=1.144 3(2)nm3,Z=4,F(000)=1 744,Mr=443.30,Dc=1.517 g/cm3,R1=0.098 3,wR2=0.110 1。通过琼脂稀释法初步测定了目标化合物4a～4d的杀菌活性,并与商品化的苯并咪唑杀菌剂麦穗宁进行对照试验。结果表明,化合物4a～4d具有良好的杀菌活性,其中化合物4d杀菌活性最高,对5个被测菌种的EC50在17.12～37.11 mg/L。     

2，4，6—三硝基苯酚衍生化β—环糊精键合硅胶液相色谱固定相的合成与评价

β-环糊精键合硅胶经对甲苯磺酰化后,与2,4,6－三硝基苯酚（PA）反应得到2,4,6－三硝基苯酚衍生化β-环糊精键合硅胶固定相（PCDS）;采用元素分析、漫反射傅里叶变换红外光谱等方法对其进行了表征;考察了PCDS对稠环芳烃、位置异构体、丹磺酰化氨基酸等物质的分离性能,并对其分离机理进行了初步探讨。     

2,4,6-三硝基苯酚衍生化β-环糊精键合硅胶液相色谱固定相的合成与评价

β_环糊精键合硅胶经对甲苯磺酰化后 ,与2 ,4 ,6_三硝基苯酚(PA)反应得到2,4,6_三硝基苯酚衍生化 β_环糊精键合硅胶固定相 (PCDS) ;采用元素分析、漫反射傅里叶变换红外光谱等方法对其进行了表征 ;考察了PCDS对稠环芳烃、位置异构体、丹磺酰化氨基酸等物质的分离性能 ,并对其分离机理进行了初步探讨。     

Determination of the Crystal Structure of a New Polymorph of Theophylline

A new approach to crystal structure determination, combining crystal structure prediction and transmission electron microscopy, was used to identify a potential new crystal phase of the pharmaceutical compound theophylline. The crystal structure was determined despite the new polymorph occurring as a minor component in a mixture with Form II of theophylline, at a concentration below the limits of detection of analytical methods routinely used for pharmaceutical characterisation. Detection and characterisation of crystallites of this new form were achieved with transmission electron microscopy, exploiting the combination of high magnification imaging and electron diffraction measurements. A plausible crystal structure was identified by indexing experimental electron‐diffraction patterns from a single crystallite of the new polymorph against a reference set of putative crystal structures of theophylline generated by global lattice energy minimisation calculations.     

有机硅改性席夫碱聚氨酯型液晶固定相的制备、表征及色谱性能

以对苯二胺、3-氯丙醇和4-羟基苯甲醛为原料,合成对苯二(对苯丙氧基醇)亚胺液晶基元,再与对苯二异氰酸酯和1,3-双(3-氨基丙基)四甲基二硅氧烷反应,合成席夫碱型硅氧烷聚氨酯液晶聚合物。 通过红外光谱法、X射线衍射、热分析、偏光显微镜等技术手段对其结构和性能进行了表征。 结果表明,该物质为席夫碱有机硅聚氨酯液晶聚合物,属于近晶相液晶,液晶区间为103~150 ℃,热分解温度为300 ℃。 用席夫碱型硅氧烷聚氨酯液晶固定相制备填充色谱柱,考察固定液的相对极性及其对取代苯位置异构体的色谱分离性能。 合成的席夫碱型硅氧烷聚氨酯液晶聚合物的液晶温度范围为103~146 ℃,属于强极性固定液(P_x=79),各组分色谱峰的分离度为0.96~3.33。     

复合镀层中ZrO2微粒对基质Ni晶体结构的影响

采用复合电沉积方法制备了Ｎｉ－ＺｒＯ２复合镀层，探讨了ＺｒＯ２微粒引起的基质金属Ｎｉ的晶体择优取向及点阵常数的变化，及其对析氢电催化活性的影响。结果表明，ＺｒＯ２微粒的存在改变了Ｎｉ的电沉积层结构，使基质金属Ｎｉ产生新的沿（２２０）晶面的择优取向。这一新的择优取向不利于析氢反应。择优取向的改变说明复合电沉积过程中，Ｎｉ与ＺｒＯ２微粒是以一定的界面匹配进入复合镀层的，基质金属Ｎｉ点阵参数的改变也证明     

Dealing with Crystal Forms (The Kingdom of Serendip?)

The variety of crystal forms that may be associated with one specific molecule of interest can be extremely large: in addition to polymorphs, all sorts of crystalline solids can be obtained, from molecular and ionic co‐crystals to hydrates/solvates, to, needless to say, polymorphs of all these new crystal forms. Lack of predictability of crystallization experiments, far from representing a failure or a nuisance, should encourage in the crystal maker the same attitude shown by the three princes of Serendip (who were making unexpected discoveries by virtue of their “sagacity and readiness of mind”) to be ready to pick new avenues as the crystal experiments will yield something unplanned for.     

Quantitative analysis of crystallization kinetics by light depolarization technique. Possibilities and limitations

The kinetics of isothermal crystallization of various polymers was investigated by light depolarization technique (LDT) using the new setup with direct registration of depolarization ratio. Experimental data were analyzed using new method proposed by Ziabicki who shown that degree of crystallinity is a non-linear function of degree of depolarization, crystal thickness, and its birefringence. Other experimental methods were involved providing supplementary information on crystal thickness (SAXS) and allowing comparison of crystallization kinetics (WAXS, DSC). The advantage of LDT relies on high sampling rate allowing on-line measurements and lack of inertia effects that exist in other methods like calorimetry. The limitations of the applicability of the method are discussed. The method needs supplementary information not only on crystal thickness but also on variable optical birefringence of real crystals. Our results show that LDT can be used in a simple way for investigation of crystallization kinetics at relatively high temperatures, providing large and perfect crystals. In such a case it is sufficient to use crystal intrinsic birefringence and final crystal thickness typical at particular temperature of crystallization. On the other hand, depolarization ratio combined with measurements by other methods (crystallinity and crystal thickness) can be used for estimation of crystal birefringence.     

Growth and studies of thiourea urea magnesium chloride (TUMC) single crystals

A new semi organic Non-linear optical (NLO) crystal thiourea urea magnesium chloride (TUMC) was grown by slow evaporation technique at room temperature. Good quality single crystals were grown within 20?days. The FTIR spectrum of title compound was recorded and vibrational assignments were made. The recorded UV?Cvis spectrum shows the optical transmission property of the crystal. The Second harmonic generation (SHG) of TUMC crystal was tested by Kurtz?CPerry method using Nd:YAG laser and the result confirms that the grown crystal exhibits NLO property. To analyse the thermal stability of the crystal TG/DTA analysis were made. Detailed structural analysis of the compound is under progress.     

Physico-chemical characterization of an active pharmaceutical ingredient

The physico-chemical properties and polymorphism of a new active pharmaceutical ingredient entity has been analyzed and the gain of knowledge during the chemical development of the substance is described. Initial crystallization revealed an anhydrous crystal form with good crystallinity and a single, sharp DSC melting peak at 171°C and a straightforward development of this crystal form seemed possible. However, during polymorphism screening, new crystalline forms were detected that were often analyzed as mixtures of crystal forms. The process of characterization and identification of the different crystalline forms and its thermodynamical relationship has been supported by a combination of experimental and computational work including determination of the three-dimensional structures of the crystal forms. The crystal structure of one polymorphic form was solved by single crystal X-ray structure analysis. Unfortunately, Mod B resisted in formation of suitable single crystals, but its structure could be solved by high resolution powder diffraction data analysis using synchrotron radiation. Calculation of the theoretical X-ray powder diffraction pattern from three dimensional crystal coordinates allowed an unambiguous identification of the different crystalline forms. Two polymorphic crystal forms of the API-CG3, named Mod A and Mod B, are enantiotropic whereas Mod B is the most stable polymorph at room temperature up to about 50°C and Mod A at temperatures above 50°C. The mechanism of the solid-solid transition can be explained by analyzing the molecular packing information gained from the single crystal structures. A third crystalline form with the highest melting peak turned out to be not a polymorphic or pseudopolymorphic crystal modification of our API-CG3 but a chemically different substance. This revised version was published online in July 2006 with corrections to the Cover Date.     

Synthesis, growth, crystal structure and characterization of a new organic material: glycine glutaric acid

Glycine glutaric acid, a new organic compound has been synthesized and good quality single crystals were grown by slow evaporation technique. The structure of the grown crystal was elucidated by using single crystal XRD. The presence of the functional groups was confirmed by using FT-IR spectroscopy. The optical transparency was studied by using UV-vis spectrophotometer and it was found that the crystal is having high optical transparency. The thermal stability of the crystal was studied by using thermo-gravimetric and differential thermal analyses and found that it is stable up to 150°C. The room temperature dielectric studies were also carried out over the wide frequency range: 10 mHz to 10 MHz.     

Synthesis,crystal growth,structural, spectral,optical, thermal and dielectric studies of a new nonlinear optical material: 4-Hydroxy-l-proline-l-tartaric acid (1:1)

Single crystals of a new organic material, 4-hydroxy-l-proline-l-tartaric acid (HPTA) adduct, were grown by slow evaporation of an aqueous solution containing equimolar concentrations of 4-hydroxy-l-proline and l-tartaric acid at room temperature. Formation of new crystal has been confirmed by single crystal X-ray diffraction and NMR spectroscopic techniques. The single crystal XRD analysis shows that a molecule of 4-hydroxy-l-proline and a molecule of free l-tartaric acid both of which are interlinked to each other by two types of H-bonding interactions, namely O(6)–H(6)⋯O(2) and N(1)–H(1B)⋯O(10). The title compound (HPTA) crystallizes in monoclinic crystal system with non-centrosymmetric space group P2₁. The suitability of the crystal for optical applications was studied by UV–Vis–NIR spectroscopy. Fourier transform infrared (FT-IR) spectral analysis was used to confirm the presence of various functional groups in the grown crystals. The thermal stability of the compound was investigated by thermogravimetric and differential thermal analyses. The dielectric constant and dielectric loss of the crystal were studied as a function of frequency and temperature. The fluorescence spectral analysis of the title crystal shows an indigo emission. The second order nonlinear optical (NLO) property of the crystal was confirmed by the modified Kurtz–Perry powder second harmonic generation (SHG) test.     

Multidentate,V-Shaped Pyridine Building Blocks as Tectons for Crystal Engineering

The formation of supramolecular structural units through self-assembly is a powerful method to design new architectures and materials endowed with specific properties. With the aim of adding a group of versatile tectons to the toolkit of crystal engineers, we have devised and synthesised four new V-shaped building blocks characterised by an aryl acetylene scaffold comprising three substituted pyridine rings connected by two triple bonds. The judicious choice of different substituents on the pyridine rings provides these tectons with distinctive steric, electrostatic and self-assembly properties, which influence their crystal structures and their ability to form co-crystals. Co-crystals of the tectons with tetraiododifluorobenzene were obtained both via traditional and mechanochemical crystallisation strategies, proving their potential use in crystal engineering. The energetic contributions of the supramolecular interactions at play in the crystal lattice have also been evaluated to better understand their nature and strength and to rationalise their role in designing molecular crystals.