微乳体系相图及其在液相色谱分离多组分药物应用的研究

采用滴加法和电导率法绘制了十二烷基硫酸钠(SDS)/正丁醇/油相(正辛醇、正辛烷、正庚烷、正己烷)/水四组分微乳体系的拟三元相图。以O/W型微乳区域大小为指标,考察不同油相、表面活性剂与助表面活性剂的质量比对微乳形成的影响,并通过测定电导率、相对粘度以及表面张力等物理化学参数,考察了微乳体系的相行为及特性。根据得到的微乳体系相图,进行色谱条件优化,建立了快速、稳定的测定阿莫西林舒巴坦匹酯片剂中阿莫西林与舒巴坦匹酯二组分含量的方法,结果显示此微乳分离系统有较好的色谱适用性及方法可行性。     

水/[NH_2 ebim][PF_6]/Triton X-100/正丁醇/环己烷微乳液体系的制备

采用自制的功能离子液体1-(胺乙基)-3-丁基咪唑六氟磷酸盐([NH_2ebim][PF6]),制备了水/[NH_2ebim][PF_6]/Triton X-100/正丁醇/环己烷微乳液体系,通过动态光散射技术测定微乳液的粒径分布和分散相浓度,通过电导率仪测定体系电导率的变化,由这两种分析方法确定微乳液类型,微乳液类型被分为表面活性剂与水的互溶相包油型(O/S+W)和水包油型(O/W),并绘制出拟三元相图;通过耗散动力学(DPD)模拟不同水含量时微乳液体系中的聚集行为,模拟结果呈现出的微乳液类型与实验测定分析结果一致,证明了相图绘制的正确性;文中还考察了Triton X-100与正丁醇的比例对微乳液区域的影响,实验结果表明,随着Triton X-100与正丁醇的比例增加微乳液区域增大。     

CTAB反相微乳体系的相行为研究

实验绘制了系列十六烷基三甲基溴化铵(CTAB)+正丁醇+正己烷+水(或CaCl2水溶液)拟三元体系相图。分别研究了正丁醇的添加比例和CaCl2水溶液的浓度对微乳区域的影响,发现随着正丁醇的相对比例逐渐增大,拟三元体系中微乳区的面积逐渐减小,表明过多增加正丁醇的量不利于微乳相的形成;发现总体上随着CaCl2水溶液摩尔浓度的增加,拟三元体系中微乳区的面积逐渐减小,表明强电解质的加入对微乳相影响较大,较高浓度的CaCl2会使部分CTAB失去表面活性而难以形成微乳液,导致微乳相区域逐渐减小。实验测定了电导率随水(或CaCl2水溶液)含量变化的规律,依据电解质理论探讨了微乳液的微观结构,并通过选择一定R0值的CaCl2微乳液与等摩尔的碳酸钠水溶液反应制备了球形纳米碳酸钙粒子。     

CTAB反相微乳液的稳定条件与纳米WO3的制备

以CTAB(十六烷基三甲基溴化铵)/正丁醇/正辛烷/钨酸钠水溶液构制反相微乳体系,通过测定体系电导率的方法确定相点并绘制反相微乳区拟三元相图。考察了该体系在不同条件下稳定存在的组成范围,选取实验最佳条件制备出纳米WO3。结果表明,表面活性剂与助表面活性剂的比、钨酸钠溶液的浓度对该反相微乳体系稳定区域的影响较大,当m(CTAB)∶m(正丁醇)=1∶2,钨酸钠浓度为0.05～0.08 g/mL时,体系有较大的反向微乳区,且当m(CTAB 正丁醇)∶m(正辛烷)=2∶3时,体系有最大溶水量;温度对该体系稳定区域的影响不大。在最适宜条件下,以0.08 g/mL的钨酸钠微乳液与盐酸微乳液,在40℃的水浴中反应7 h,制备出平均粒径约30 nm的WO3纳米粒子。     

微乳液体系相图的研究及其在纳米氟化物制备中的应用

绘制了十六烷基三甲基溴化铵(CTAB)/正丁醇(n-C₄H₉OH)/正辛烷(n-C₈H₁₈)/水[或NH₄F溶液、或Ba(NO₃)₂溶液、或KNO₃-Mg(NO₃)₂混合溶液]四组分微乳体系的拟三元相图.观察了电导率随水(或盐溶液)含量变化的规律,很好地印证了微乳液体系的相行为.选取相图中微乳区点作为最佳条件,制备了KMgF₃纳米粒子.     

磁场对苯胺微乳液聚合体系相行为的影响

通过十二烷基苯磺酸钠(SDBS)/正丁醇(n-butanol)/苯胺/水微乳液体系的拟三元相图,考察了恒定磁场(0.4T)和助表面活性剂与表面活性剂的质量比(Km=mn-butanol/mSDBS)对苯胺微乳液聚合体系的相行为、电导行为以及微乳化作用的影响.结果表明:随着体系醇含量的增加,微乳区面积先增大后减小,当Km值为1.0时,形成的微乳区最大;外加磁场可以增大微乳区面积.通过对外加磁场条件下溶液电导率随水含量变化规律的分析,印证了拟三元相图的表征结果.透射电镜分析结果表明,磁场条件下合成的聚苯胺颗粒比无磁场条件下合成的聚苯胺颗粒小.     

载药微乳液相行为的研究

提出了一种基于相图研究实现纳米药物载体可控制备的方法.采用微乳液控温相图绘制装置绘制了硬脂酸聚烃氧(40)酯(S-40)/聚氧乙烯聚氧丙烯醚嵌段共聚物(F-68)/单硬脂酸甘油酯(GMS)/水体系的拟三元相图,基于电导率测定值确定了微乳液的结构(W/O、双连续相和O/W),该体系同时存在液晶区域.乳化剂S-40/F-68的质量比为7:3.研究了脂溶性药物维甲酸(RA)对微乳液相行为的影响，结果表明RA的加入对微乳液的相行为影响较小.基于相图研究结果制备了维甲酸固体脂质纳米粒(RA-SLN),亚微米粒度分析仪(PCS)测定的平均粒径和透射电镜测试都表明RA-SLN为10 nm左右的球状粒子.     

十二烷基苯磺酸钠微乳体系制备纳米Fe2O3

十二烷基苯磺酸钠微乳体系制备纳米Fe2O3;微乳;电导率;萃取率;纳米Fe2O3     

β-胡萝卜素微乳液的制备及其稳定性研究

通过绘制拟三元相图选择合适的微乳液组分,制备了β-胡萝卜素的Tween80/乙醇/丁酸乙酯/H2O的O/W型微乳液。考察了温度、盐度和pH对微乳液区域的影响:电导率法区分了微乳液的O/W、W/O和B.C(油-水双连续型)区域;对相同浓度β-胡萝卜素的微乳液和丁酸乙酯溶液进行了光、热稳定性研究,用紫外分光光度法测定样品中β-胡萝卜素的残存率。结果表明,温度升高和pH降低使微乳区稍有减小,盐度对微乳区基本无影响;微乳体系中水的质量分数大于61·5%时形成O/W型微乳液;β-胡萝卜素在微乳液和丁酸乙酯溶液中对光和热都比较敏感,但在微乳液中较稳定。     

三组分相图测绘中多个绿色化实验体系的确立

针对大学化学三组分体系液-液平衡相图测绘实验中乙酸正丁酯腐蚀滴定管聚四氟乙烯旋塞问题进行了实验方法改进，将原来的体积量取法更改为体积量取与质量量取相配合的实验操作方法。并在此基础上，考察了几种新的绿色化实验体系——醋酸丙酯/正己醇/醋酸异丙酯-乙醇-水体系在该实验中的操作可行性，最后对它们的实验效果进行了比较。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.