荧光1,2,4-噻二唑-3,5-二酮衍生物的合成及其对精子的标记作用

合成了3个含有荧光基团的1,2,4-噻二唑-3,5-二酮衍生物,其结构经¹H NMR,¹³C NMR, HR-MS(ESI)表征,并考察了这些衍生物对精子的制动活性和荧光标记作用。结果表明：与先导化合物Tideglusib相比,目标化合物均保持了较强的杀精活性,且在紫外光激发下,具有相似的荧光标记模式。     

N-(4,6-二取代嘧啶-2-基)-N'-(1-甲基-3-乙基-4-氯吡唑-5-基)甲酰基(硫)脲的合成及生物活性

利用活性结构拼接原理,将高效杀螨剂吡螨胺分子的吡唑环部分引入酰基（硫）脲化合物中,以1-甲基-3-乙基-4-氯-5-甲酸基吡唑和2-氨基-4,6-二取代嘧啶为起始原料,通过多步反应合成了5种N-（4,6-二取代嘧啶-2-基）-N’-（1-甲基-3-乙基-4-氯吡唑-5-基）甲酰基脲和5个N-（4,6-二取代嘧啶-2．基）-N’-（1．甲基-3-乙基-4-氯吡唑-5-基）甲酰基硫脲化合物,其化合物结构经IR、^1HNMR及元素分析测试技术确证。初步生物活性试验表明,在50mg／L质量浓度下目标化合物的杀螨活性不太理想,但有些化合物具有较好的除草活性,其中化合物Ib、Ic和Ie对稗草主根的生长抑制率大于60％。     

N-[2-(1H-吲哚-3)乙基]-2-乙酰噻唑-4-甲酰胺及其类似物的合成

N-[2-(1H-吲哚-3)乙基]-2-乙酰噻唑-4-甲酰胺是最近从海洋细菌中分离得到的一种新型的天然杀藻剂, 以D-丙氨酸为原料合成了该化合物, 并用类似的方法首次合成了它的类似物2, 3和4. 其关键步骤为通过将取代的4-噻唑甲酸制成混酐与色胺连接的偶联反应. 各中间体都通过¹H NMR和¹³C NMR得到证实. 最终产品通过¹H NMR, ¹³C NMR和HRMS证实, 与文献所报道相一致.     

高效液相色谱-荧光检测法同时测定全血中5种香豆素类杀鼠剂

建立了同时测定全血中杀鼠灵、杀鼠迷、溴敌隆、氟鼠灵与溴鼠灵等5种香豆素类杀鼠剂的简便、灵敏、准确的高效液相色谱-变波长荧光分析方法。全血样品经乙酸乙酯提取后,在XDB C18柱(150 mm×2.1 mm, 5 μm)上以甲醇-0.2%乙酸水溶液(体积比为88∶12)混合液为流动相,采用荧光变波长程序检测,同时通过建立各杀鼠剂的荧光光谱库,利用谱库检索,提高定性的准确度。各杀鼠剂的线性范围为0.01~10.00 mg/L（杀鼠灵为0.05~10.00 mg/L）,检出限为0.01~0.05 mg/L,方法的加标回收率为81%～98%,其相对标准偏差（RSD）为3.8%～8.5%。该法适用于中毒病人的中毒诊断检测。     

液相色谱-串联质谱同时测定家禽组织中16种磺胺残留

5g家禽组织样品,用乙腈提取,旋转蒸发器减压蒸干后,用乙腈0．01mol／L乙酸铵溶液溶解（12：88,V/V）,用正己烷去除脂肪后,样液用高效液相色谱分离,电喷雾串联四级杆质谱进行检测,外标法定量。本方法研究的16种磺胺（磺胺甲噻二唑、磺胺醋酰、磺胺嘧啶、磺胺氯哒嗪、磺胺甲基异唔唑、磺胺甲基嘧啶、磺胺吡啶、磺胺二甲异嘌唑、磺胺-6-甲氧嘧啶、磺胺邻二甲氧嘧啶、磺胺甲氧哒嗪、磺胺间二甲氧嘧啶、磺胺噻唑、磺胺二甲嘧啶、磺胺甲氧嘧啶、磺胺苯吡唑）的线性范围为0．2—120ng,线性相关系数r〉0．995;在2．5—600μg/kg的4个添加水平范围内的平均回收率为75．4％-97．3％;相对标准偏差为3．48％-14．09％;方法检出限（LOD）为1．0—12．0μg／kg;方法定量限（LOQ）为2．0—24．0μg/kg。     

8-氮杂双环[3.2.1]辛烷-3-异噁唑肟类衍生物的合成及其杀线虫活性

基于具有潜在杀线虫活性的托烷衍生物结构,通过1,3-偶极环加成反应,设计合成了19个未见报道的8-氮杂双环[3.2.1]辛烷-3-异噁唑肟类衍生物,通过~1H NMR,~(13)C NMR和高分辨质谱对目标化合物的结构进行表征.初步的生物活性测试表明:在浓度25 mg/L下,目标化合物对南方根结线虫表现出良好的抑制活性,活性最好的化合物8-甲基-8-氮杂双环[3.2.1]辛烷-3-酮-O-((3-(4-硝基苯基)-4,5-二氢异噁唑-5-基)甲基)肟(9e)在1 mg/L浓度下对根结线虫的抑制率达55.6%.     

N-烷基-O-烷基-O-(1-氰基-2,2,2-三氯乙基) 硫代磷酰胺酯的合成

本文报道了八种新的化合物N-烷基-O-烷基-O-(1-氰基-2,2,2-三氯乙基)硫代磷酰胺酯的合成. 用IR, NMR和MS确定了化合物的结构, 部分化合物具有优良的杀线虫活性.     

基于Fe3O4@Ag壳核结构磁性纳米复合物的对杀螟硫磷的电化学传感

制备一种壳核结构的Fe3O4@Ag磁性纳米粒子,将该纳米粒子通过壳聚糖（CS）修饰在玻碳电极（GCE）表面,制备了对杀螟硫磷有灵敏电化学传感的Fe3O4@Ag/CS/GCE。应用透射电镜（TEM）和紫外可见光谱（UV-VIS）,对Fe3O4@Ag纳米粒子进行表征。运用电化学交流阻抗（EIS）、循环伏安法（CV）和时间电流法（I-T）来研究杀螟硫磷电化学特性。研究发现,在1.74×10-7～3.27×10–4 mol/L浓度范围内,该传感器可以实现对杀螟硫磷的快速检测,检测限为5.7×10-8 mol/L（S/N=3）     

杀螨王及其代谢物残留总量的气相色谱分析法

报道了杀螨王（fenpyroximate）及其代谢物顺式体在HCl-H2SO4混合液中定量分解为可经气相色谱分析的1,3-二甲基-5-苯氧基吡唑-4-醛,建立了苹果、柑桔和土壤样品中残留总量的气相色谱分析法。添加浓度0.05～1.0mg/kg,苹果、桔皮、桔肉和土壤样品中杀螨王总量平均回收率分别为104.7～124.8%,90.9～93.8%,89.3～94.0%和104.3～113.0%,变异系数依次为3.3～11.8%,2.7～7.5%,1.4～2.7%和1.5～4.0%。     

气相色谱-微池电子捕获检测器分析茶叶中杀螟丹的残留

介绍了一种快速、灵敏、可靠的适用于茶叶样品中杀螟丹残留量的气相色谱分析方法。茶叶样品经过0.05 mol/L盐酸溶液提取,液-液分配净化,在碱性条件下用正己烷萃取提取液中的杀螟丹,用毛细管气相色谱法-微池电子捕获检测器（μ-ECD）测定杀螟丹的残留量。结果表明：样品的添加回收率为70.2%~92.0%,相对标准偏差小于10%,方法的检测低限为0.01 mg/kg,符合农药残留分析的要求。     

Selective Killing of Breast Cancer Cells by Doxorubicin‐Loaded Fluorescent Gold Nanoclusters: Confocal Microscopy and FRET

Fluorescent gold nanoclusters (AuNCs) capped with lysozymes are used to deliver the anticancer drug doxorubicin to cancer and noncancer cells. Doxorubicin‐loaded AuNCs cause the highly selective and efficient killing (90 %) of breast cancer cells (MCF7) (IC₅₀=155 nm ). In contrast, the killing of the noncancer breast cells (MCF10A) by doxorubicin‐loaded AuNCs is only 40 % (IC₅₀=4500 nm ). By using a confocal microscope, the fluorescence spectrum and decay of the AuNCs were recorded inside the cell. The fluorescence maxima (at ≈490–515 nm) and lifetime (≈2 ns), of the AuNCs inside the cells correspond to Au_10–13. The intracellular release of doxorubicin from AuNCs is monitored by Förster resonance energy transfer (FRET) imaging.     

Drug Self‐Delivery Systems Based on Hyperbranched Polyprodrugs towards Tumor Therapy

Amphiphilic hyperbranched polyprodrugs (DOX‐S‐S‐PEG) with drug repeat units in hydrophobic core linked by disulfide bonds were developed as drug self‐delivery systems for cancer therapy. The hydroxyl groups and the amine group in doxorubicin (DOX) were linked by 3,3′‐dithiodipropanoic acid as hydrophobic hyperbranched cores, then amino‐terminated polyethylene glycol monomethyl ether (mPEG‐NH₂) as hydrophilic shell was linked to hydrophobic cores to form amphiphilic and glutathione (GSH)‐responsive micelle of hyperbranched polyprodrugs. The amphiphilic micelles can be disrupted under GSH (1 mg mL^?1) circumstance. Cell viability of A549 cells and 293T cells was evaluated by CCK‐8 and Muse Annexin V & Dead Cell Kit. The disrupted polyprodrugs maintained drug activity for killing tumor cells. Meanwhile, the undisrupted polyprodrugs possessed low cytotoxicity to normal cells. The cell uptake experiments showed that the micelles of DOX‐S‐S‐PEG were taken up by A549 cells and distributed to cell nuclei. Thus, the drug self‐delivery systems with drug repeat units in hydrophobic cores linked by disulfide bonds showed significant special advantages: 1) facile one‐pot synthesis; 2) completely without toxic or non‐degradable polymers; 3) DOX itself functions as fluorescent labeled molecule and self‐delivery carrier; 4) drug with inactive form in hyperbranched cores and low cytotoxicity to normal cells. These advantages make them excellent drug self‐delivery systems for potential high efficient cancer therapy.     

Mechanism‐Guided Design and Synthesis of a Mitochondria‐Targeting Artemisinin Analogue with Enhanced Anticancer Activity

Understanding the mechanism of action (MOA) of bioactive natural products will guide endeavor to improve their cellular activities. Artemisinin and its derivatives inhibit cancer cell proliferation, yet with much lower efficiencies than their roles in killing malaria parasites. To improve their efficacies on cancer cells, we studied the MOA of artemisinin using chemical proteomics and found that free heme could directly activate artemisinin. We then designed and synthesized a derivative, ART‐TPP, which is capable of targeting the drug to mitochondria where free heme is synthesized. Remarkably, ART‐TPP exerted more potent inhibition than its parent compound to cancer cells. A clickable probe ART‐TPP‐Alk was also employed to confirm that the attachment of the TPP group could label more mitochondrial proteins than that for the ART derivative without TPP (AP1). This work shows the importance of MOA study, which enables us to optimize the design of natural drug analogues to improve their biological activities.     

Calcium as a modulator of photosensitized killing of H9c2 cardiac cells.

Illumination of H9c2 rat heart cells in the presence of Rose Bengal resulted in dose-dependent cell killing (assessed by trypan blue staining) and modification of ionic currents flowing through the heart cell membrane. Inhibitors of voltage-gated ionic currents were shown to have little effect on cell killing. Ionic current measurements were used to assess the increase in leak conductance of these cells, which has been suggested to be a causal factor in killing of other cell types (1). Inhibitors of voltage-gated ionic currents, including the sodium channel blocker tetrodotoxin (100 microM) and the calcium channel blocker lanthanum (10 microM) were shown to have little effect on cell killing. The potassium channel inhibitor tetraethylammonium (20 mM) inhibited cell killing, but the effect is viewed as being caused by an inhibition of leak current. The time course of block of voltage-activated ionic currents during illumination, in the presence of Rose Bengal, was rapid compared with that for induction of leak current and for cell killing. These observations are consistent with a role for leak current in photosensitized killing of cardiac cells. They are interpreted with respect to calcium influx through the leak current pathway as a trigger for the cellular response.     

Theoretical Encapsulation of Fluorouracil (5-FU) Anti-Cancer Chemotherapy Drug into Carbon Nanotubes (CNT) and Boron Nitride Nanotubes (BNNT)

Introduction: Chemotherapy with anti-cancer drugs is considered the most common approach for killing cancer cells in the human body. However, some barriers such as toxicity and side effects would limit its usage. In this regard, nano-based drug delivery systems have emerged as cost-effective and efficient for sustained and targeted drug delivery. Nanotubes such as carbon nanotubes (CNT) and boron nitride nanotubes (BNNT) are promising nanocarriers that provide the cargo with a large inner volume for encapsulation. However, understanding the insertion process of the anti-cancer drugs into the nanotubes and demonstrating drug-nanotube interactions starts with theoretical analysis. Methods: First, interactions parameters of the atoms of 5-FU were quantified from the DREIDING force field. Second, the storage capacity of BNNT (8,8) was simulated to count the number of drugs 5-FU encapsulated inside the cavity of the nanotubes. In terms of the encapsulation process of the one drug 5-FU into nanotubes, it was clarified that the drug 5-FU was more rapidly adsorbed into the cavity of the BNNT compared with the CNT due to the higher van der Waals (vdW) interaction energy between the drug and the BNNT. Results: The obtained values of free energy confirmed that the encapsulation process of the drug inside the CNT and BNNT occurred spontaneously with the free energies of −14 and −25 kcal·mol⁻¹, respectively. Discussion: However, the lower value of the free energy in the system containing the BNNT unraveled more stability of the encapsulated drug inside the cavity of the BNNT comparing the system having CNT. The encapsulation of Fluorouracil (5-FU) anti-cancer chemotherapy drug (commercial name: Adrucil^®) into CNT (8,8) and BNNT (8,8) with the length of 20 Å in an aqueous solution was discussed herein applying molecular dynamics (MD) simulation.     

Targeted Drug Delivery Biopolymers Effectively Inhibit Breast Tumor Growth and Prevent Doxorubicin-Induced Cardiotoxicity

The anticancer agent doxorubicin(dox) has been widely used in the treatment of a variety of hematological malignancies and solid tumors. Despite doxorubicin’s efficiency in killing tumor cells, severe damage to healthy tissues, along with cardiotoxicity, limits its clinical use. To overcome these adverse side effects, improve patient safety, and enhance therapeutic efficacy, we have designed a thermally responsive biopolymer doxorubicin carrier that can be specifically targeted to tumor tissue by locally applying mild hyperthermia (41 °C). The developed drug vehicle is composed of the following: a cell penetrating peptide (SynB1) to promote tumor and cellular uptake; thermally responsive Elastin-like polypeptide (ELP); and the (6-maleimidocaproyl) hydrazone derivative of doxorubicin (DOXO-EMCH) containing a pH-sensitive hydrazone linker that releases doxorubicin in the acidic tumor environment. We used the in vivo imaging system, IVIS, to determine biodistribution of doxorubicin-delivered ELP in MDA-MB-231 xenografts in nude mice. Tumor bearing mice were treated with a single IV injection of 10 mg/kg doxorubicin equivalent dose with free doxorubicin, thermally responsive SynB1 ELP 1-DOXO, and a thermally nonresponsive control biopolymer, SynB1 ELP 2-DOXO. Following a 2 h treatment with hyperthermia, tumors showed a 2-fold higher uptake when treated with SynB1 ELP 1-DOXO compared to free doxorubicin. Accumulation of the thermally non-responsive control SynB1 ELP2 –DOXO was comparable to free doxorubicin, indicating that an increase in dox accumulation with ELP is due to aggregation in response to thermal targeting. Higher levels of SynB1 ELP1–DOXO and SynB1 ELP2 –DOXO with respect to free doxorubicin were observed in kidneys. Fluorescence intensity from hearts of animals treated with SynB1 ELP1–DOXO show a 5-fold decrease in accumulation of doxorubicin than the same dose of free doxorubicin. SynB1-ELP1-DOXO biopolymers demonstrated a 6-fold increase in tumor/heart ratio in comparison to free doxorubicin, indicating preferential accumulation of the drug in tumors. These results demonstrate that thermally targeted polymers are a promising therapy to enhance tumor targeting and uptake of anticancer drugs and to minimize free drug toxicity in healthy tissues, representing a great potential for clinical application.     

Morphology Regulation in Redox Destructible Amphiphilic Block Copolymers and Impact on Intracellular Drug Delivery

In two ABA type amphiphilic block copolymers (P1, P2), the hydrophobic B block consists of a bioreducible segmented poly(disulfide) (PDS), while poly‐N‐isopropylacrylamide (PNIPAM) or poly(triethyleneglycol)methylether‐methacrylate (PTEGMA) serve as the hydrophilic A blocks in P1 and P2, respectively, leading to the formation of polymersome and micelle, owing to the difference in the packing parameters. Both exhibit comparable doxorubicin (Dox) encapsulation efficiency, but glutathione (GSH) triggered release appears much faster from the polymersome than micelle owing to the complete degradation of the PDS segment in polymersome morphology unlike in micelle. Dox‐loaded polymers (P1‐Dox and P2‐Dox) exhibit minimum toxicity to normal cells like C2C12. By contrast, P1‐Dox shows excellent killing efficiency to the HeLa cells (cancer cell) (in which the GSH concentration is significantly higher). However, P2‐Dox reveals a rather poor activity even to HeLa cells. Fluorescence microscopy studies show comparable cellular uptake of P1‐Dox and P2‐Dox. But the polymersome entrapped dye escapes fast from the cargo and reach the nucleus, while the drug‐loaded micelle remains trapped in the perinuclear zone explaining the significant difference in the drug delivery performance of polymersome and micelle.     

Graphdiyne Micromotors in Living Biomedia

Graphdiyne (GDY), a new kind of two-dimensional (2D) material, was combined with micromotor technology for “on-the-fly” operations in complex biomedia. Microtubular structures were prepared by template deposition on membrane templates, resulting in functional structures rich in sp and sp² carbons with highly conjugated π networks. This resulted in a highly increased surface area for a higher loading of anticancer drugs or enhanced quenching ability over other 2D based micromotors, such as graphene oxide (GO) or smooth tubular micromotors. High biocompatibility with almost 100 % cell viability was observed in cytotoxicity assays with moving micromotors in the presence of HeLa cells. On a first example, GDY micromotors loaded with doxorubicin (DOX) were used for pH responsive release and HeLa cancer cells killing. The use of affinity peptide engineered GDY micromotors was also illustrated for highly sensitive and selective fluorescent OFF–ON detection of cholera toxin B through specific recognition of the subunit B region of the target toxin. The new developments illustrated here offer considerable promise for the use of GDY as part of micromotors in living biosystems.     

三明治结构rGO/Fe3O4@mSiO2载体的构筑及协同抗肿瘤性能

采用温和的反应条件,制备出三明治结构rGO/Fe_3O_4@mSiO_2,利用SEM、TEM、FTIR、XRD和N_2吸附-脱附等对其形貌和性能进行表征,考查了其对Hela细胞的毒性和细胞荧光成像效果,并探讨了其形成机理。实验结果表明:rGO/Fe_3O_4@mSiO_2具有较高的比表面积(217 m~2·g~(-1)),对抗癌药物五氟尿嘧啶(5-FU)的载药率达到57.34%;它还具有较好的磁性,磁饱和强度为32 emu·g-1;而且rGO/Fe_3O_4@mSiO_2纳米复合物在光照条件下具有优异的光热转换性能,对He La细胞表现出明显的杀伤效果。     

IMINIUM SALT OF COPPER BENZOCHLORIN (CDS1), A NOVEL PHOTOSENSITIZER FOR PHOTODYNAMIC THERAPY: MECHANISM OF CELL KILLING

The mechanism of cell killing by CDS1, an iminium salt of octaethylbenzochlorin with copper in the aromatic ring, in combination with light from a noncoherent light source was investigated. Using a standard clonogenic assay and the AY-27 FANFT turnor line. photoactivation of CDS1 was shown to be cytotoxic. The photodynamic cell killing ability of CDS1 required the presence of molecular oxygen. The reactive species generated by light activation of CDS1 were effectively quenched by N.N' -diphenyl- p -phenylenediamine. Additionally, the photodynamic effect of CDS1 was not cnhanced by dcuterium oxide. To characterize the reactive oxygen species generated by the photoactivation of CDS1 the well-characterized erythrocyte ghost model was used. Superoxide dismutase and catalase were potcnt inhibitors of CDS1-induced lipid peroxidation of erythrocyte membranes. Sodium azide only partially inhibited lipid peroxidation. These findings differed from the known singlet oxygen generator, tin (II) etiopurpurin dichloride (SnET₂). Sodium azide was a potent inhibitor of SnET₂-induced lipid peroxidation, whereas superoxide dismutase and catalase were totally ineffective. Based on these results, we conclude that CDS1 requires the presence of molecular oxygen for cell killing to occur but appcars to act primarily through a non-singlet oxygen mechanism.