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合成了13种N-取代靛蓝衍生物,其中6种为新化合物.研究了靛蓝的N-取代衍生物与抗痛活性的关系,发现大多数N-取代靛蓝衍生物与靛玉红有相似的抗癌活性,某些甚至离于綻玉红的抗癌活性. 相似文献
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利用密度泛函方法, 基于靛蓝的电子结构, 对其锌离子络合物的可能结构及其光学性质进行了系列理论预测和分析. 计算结果表明, 异构体的不同轨道电子跃迁机理使得靛蓝异构体具有不同的吸收光谱. 理论上计算得到的4种靛蓝锌离子稳定络合物中, 有3种是以顺式靛蓝为配体, 可以预测络合反应中同时应该伴有靛蓝的异构过程, 由络合物的光化学特征可以预测, 靛蓝作为有机染料指示剂在金属离子标定的反应过程中可能生成不同的靛蓝金属络合物分子. 相似文献
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研究了1-正-辛基-3,3-二甲基-吲哚啉-2,2′-螺-5′,6′-(2-溴-4-硝基-苯并)吡喃, 1-正-辛基-3,3-二甲基-吲哚啉-2,2′-螺-5′,6′-(4-硝基-苯并)吡喃, 1-正-辛基-3,3-二甲基-吲哚啉-2,2′-螺-5′,6′-(2,4-二硝基-苯并)吡喃及1-正-辛基-3,3-二甲基-吲哚啉-2,2′螺-5′6′-(2-氯-4-硝基-苯并)吡喃在环已烷和甲苯溶液中光致开环过程的瞬态吸收光谱。观察到具有较长寿命的中间体及聚集体的存在。初步提出异构化反应过程的机制中既包含有三重态过程, 也有单重态参与。 相似文献
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采用甲醇蒸气作为碳源对甲基弯菌IMV 3011进行驯化培养,然后逐渐增加液态甲醇的浓度使其适应,得到了能耐受甲醇(φ(MeOH)=1%)的甲基弯菌IMV 3011.对甲基弯菌IMV 3011进行甲烷-甲醇共培养可得到大量具有甲烷单加氧酶(MMO)活性的细胞.研究了添加甲醇对甲基弯菌IMV 3011生长和MMO活性的影响,发现甲醇能够促进甲基弯菌IMV3011的生长.在批式反应器中,添加甲醇能够提高甲基弯菌IMV 3011的催化环氧化能力,说明甲醇可以作为电子供体通过再生辅酶NADH驱动环氧丙烷合成.考察了在膜反应器中用细胞悬浮液连续合成环氧丙烷的可行性.结果表明,通过192 h连续抽提产物环氧丙烷,避免了其对环氧化反应的抑制,流出液中环氧丙烷的浓度仍保持在1.35 mmol/L左右. 相似文献
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溴酸钾氧化靛红催化光度法测定痕量亚硝酸根 总被引:11,自引:3,他引:11
基于磷酸介质中NO2^-催化溴酸钾氧化靛红的褪色反应,建立了测定痕量NO2^-的新方法,并讨论了其动力学条件。方法检测限为1.36×10^-6g/L,线性范围0.3 ̄2μg/25mL,方法简便,已用于环境水样中痕量NO2^-的测定。 相似文献
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靛蓝二磺酸钠褪色分光光度法测定水中臭氧 总被引:1,自引:0,他引:1
在pH 2.0的磷酸-磷酸氢二钠缓冲溶液中,臭氧可使靛蓝二磺酸钠溶液褪色,且褪色程度与臭氧含量呈线性关系,据此提出了测定水中臭氧的方法。试验结果表明:靛蓝二磺酸钠的最大吸收波长为610 nm,臭氧的质量浓度在0.12~3.0 mg.L-1范围内与吸光度变化值呈线性,表观摩尔吸光率为1.8×104L.mol-1.cm-1。应用此方法测定了水中臭氧的含量,测得相对标准偏差(n=20)在0.6%~2.8%之间。 相似文献
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Claudia Ross Dr. Kirstin Scherlach Florian Kloss Prof. Dr. Christian Hertweck 《Angewandte Chemie (International ed. in English)》2014,53(30):7794-7798
Polyynes (polyacetylenes), which are produced by a variety of organisms, play important roles in ecology. Whereas alkyne biosynthesis in plants, fungi, and insects has been studied, the biogenetic origin of highly unstable bacterial polyynes has remained a riddle. Transposon mutagenesis and genome sequencing unveiled the caryoynencin (cay) biosynthesis gene cluster in the plant pathogen B. caryophylli, and homologous gene clusters were found in various other bacteria by comparative genomics. Gene inactivation and phylogenetic analyses revealed that novel desaturase/acetylenase genes mediate bacterial polyyne assembly. A cytochrome P450 monooxygenase is involved in the formation of the allylic alcohol moiety, as evidenced by analysis of a fragile intermediate, which was stabilized by an in situ click reaction. This work not only grants first insight into bacterial polyyne biosynthesis but also demonstrates that the click reaction can be employed to trap fragile polyynes from crude mixtures. 相似文献
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制备了掺杂靛红的聚吡咯(PPy)膜修饰电极,这种功能化PPy膜电极具有很好的电色效应,其颜色变化明显,响应时间短,稳定性好,是一种新型电色材料。 相似文献
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建立了超高效液相色谱-质谱联用法测定青黛中非法掺入的染色物质孔雀石绿、隐色孔雀石绿、天青A、天青B、天青C和亚甲基蓝的检测方法.样品经乙腈溶液(含5%甲酸)提取,采用超高效液相色谱-串联三重四极杆质谱(UPLC-MS/MS)的多反应监测模式(MRM)进行定性和定量检测,其中孔雀石绿、隐色孔雀石绿内标法定量,天青A、天青B、天青C、亚甲基蓝外标法定量.6种染色物质测定的线性范围在1~30 ng/m L之间,孔雀石绿、隐色孔雀石绿、天青A、天青B、天青C、亚甲基蓝的检出限分别为0.5、0.5、1.0、1.0、1.0、1.0 ng/g,定量限分别为1.0、1.0、2.0、2.0、2.0、2.0 ng/g,3个水平的回收率在79.7%~119.7%之间,精密度的RSD%在0.7%~1.8%之间.方法前处理简单,灵敏度高,适用青黛中非法掺入的染色物质孔雀石绿、隐色孔雀石绿、天青A、天青B、天青C和亚甲基蓝的快速检测. 相似文献
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Sabrin R. M. Ibrahim Sana A. Fadil Haifa A. Fadil Rawan H. Hareeri Hossam M. Abdallah Gamal A. Mohamed 《Molecules (Basel, Switzerland)》2022,27(18)
Marine sponges continue to attract remarkable attention as one of the richest pools of bioactive metabolites in the marine environment. The genus Smenospongia (order Dictyoceratida, family Thorectidae) sponges can produce diverse classes of metabolites with unique and unusual chemical skeletons, including terpenoids (sesqui-, di-, and sesterterpenoids), indole alkaloids, aplysinopsins, bisspiroimidazolidinones, chromenes, γ-pyrones, phenyl alkenes, naphthoquinones, and polyketides that possessed diversified bioactivities. This review provided an overview of the reported metabolites from Smenospongia sponges, including their biosynthesis, synthesis, and bioactivities in the period from 1980 to June 2022. The structural characteristics and diverse bioactivities of these metabolites could attract a great deal of attention from natural-product chemists and pharmaceuticals seeking to develop these metabolites into medicine for the treatment and prevention of certain health concerns. 相似文献
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Isomeric Diruthenium Complexes Bridged by Deprotonated Indigo in cis and trans Configuration 下载免费PDF全文
Madhumita Chatterjee Prabir Ghosh Katharina Beyer Dr. Alexa Paretzki Dr. Jan Fiedler Prof. Dr. Wolfgang Kaim Prof. Dr. Goutam Kumar Lahiri 《化学:亚洲杂志》2018,13(1):118-125
The doubly deprotonated form L2? of indigo=H2L can bind two [Ru(acac)2] complex fragments in the cis ( 1 ) and trans configuration ( 2 ), as evidenced from crystal structure analysis. While the latter type of N,O; N ’ ,O ’ coordination has been observed earlier, for example, with [Ru(bpy)2]2+, leading to two equivalent six‐membered ring chelates, the cis arrangement in 1 is observed here for the first time in a dinuclear complex, producing one five‐membered ring chelate with N,N ’ coordination and one seven‐membered chelate with O,O ’ coordination. The different structures of the isomers result in differing electrochemical and spectroelectrochemical (EPR, UV‐Vis‐NIR) responses for various accessible charge states 1 n and 2 n, n=–, 0, +, 2+. The associated electronic structures were analyzed by DFT (structures, spin density) and TD‐DFT calculations (electronic transitions), revealing mainly metal‐based reduction but largely indigo ligand‐based oxidation of both neutral precursors. 相似文献