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1.
喜树碱是一种天然抗癌药物,通过对喜树碱20位羟基的修饰和对喜树碱E环扩环,来提高该类化合物的活性并减小毒性,起到更好的治疗效果。简单介绍喜树碱衍生物的研究现状及其未来的发展趋势。  相似文献   

2.
20(S)-O-喜树碱肉桂酸酯衍生物的合成及其抗肿瘤活性研究   总被引:1,自引:0,他引:1  
段华鑫  张殊佳  周鹏 《有机化学》2009,29(5):724-729
为了提高喜树碱内酯环的稳定性降低其毒性, 增加其抗肿瘤效能, 以喜树碱为先导化合物, 通过酯化反应直接合成了17个20(S)-喜树碱肉桂酸酯衍生物, 并采用MTT法测定了对于人胃癌细胞SGC-7901的体外抗肿瘤活性, 活性测试结果表明有些化合物的抑制活性明显高于母体化合物喜树碱.  相似文献   

3.
喜树碱结构与活性的关系   总被引:2,自引:0,他引:2  
喜树碱是从我国特有植物喜树中分离得到的。它是一种广谱抗癌药物,对多种肿瘤有疗效,但同时也有副作用。为了寻找一种既具抗癌活性,毒性又小的喜树碱类似物,国外学者对喜树的五个环分别进行了修饰,并对修饰产物进行了药理研究,找到了抗癌活性与结构之间的关系。本文着重介绍他们的研究结果并简要总结一下喜树碱的结构、性质。  相似文献   

4.
以穿心莲内酯为先导化合物,在其3-位和19-位进行结构修饰,设计并合成了3个新型的脱水穿心莲内酯环磷酸酯类衍生物(1a~1c),其结构经1HNMR,IR和MS表征。体外抗肿瘤活性测试结果表明,1a~1c对舌癌Tca-8113细胞具有较好的体外抑制活性。  相似文献   

5.
喜树碱(Camptothecin,CPT)是美国化学家Wall和Wani在1966年首先从中国珙桐科植物喜树(Camptothecaacuminata)中提取出来的一种生物碱.试验表明它对许多实体瘤有抗肿瘤活性.药物学家对喜树碱分子的结构修饰,大多数集中在喜树碱的A,B和E环上.喜树碱的C环上5-位取代往往降低活性.我们在制备喜树碱烷基化衍生物过程中发现,喜树碱及其衍生物在碳酸钾和活泼溴代烷作用下得到5-位烷基化产物,用不同的溴代烷分别得到单取代或双取代产物.我们合成的5-位烷基化的喜树碱衍生物经过人肿瘤细胞(KB,KB/VCR,A549,HCT-8,Bel7402,A2780)的体外筛选实验,表明这一类化合物细胞毒性显著降低甚至丧失,这可能是因为取代基的空间位阻作用影响了D环羰基和受体的结合.  相似文献   

6.
王玉霞  陈帅  朱晨光 《化学研究》2019,30(3):254-259
本文合成了三种新的萘酰亚胺衍生物,并对其体外抗肿瘤活性进行了评价.初步实验结果表明,以芳基修饰氨萘菲特芳环上氨基所得化合物体外活性不如阳性对照氨萘菲特.而利用1,4-丁二醇修饰4-溴-1,8-萘酐芳环上溴原子得到的化合物3与阳性对照及其它两种衍生物相比对肝癌细胞HepG2具有较低的IC_(50)值.  相似文献   

7.
喜树碱及其类似物结构修饰与构效关系研究进展   总被引:7,自引:2,他引:5  
本文对喜树碱“嵌入式”和“药物堆积”两种主要的药物作用模式,结构A、B、C、D、E环上优势位置及活性基团的取代和结构修饰,以及构效之间的关系进行综述,并提出今后结构修饰、定量构效关系及喜树碱的传输途径等研究方向。  相似文献   

8.
选择天然产物齐墩果酸进行炔基化修饰(OA-alkyne),与环金属铱前体CycloIr-N3在铜催化条件下发生叠氮-炔环加成(CuAAC)反应,得到新的环金属铱配合物CycloIr-OA,通过1H NMR、ESI-MS对配体及配合物进行了表征。配合物具有良好的脂溶性,可以快速进入细胞。用MTT法、激光共聚焦成像及流式细胞术对CycloIr-OA的抗肿瘤活性和抗癌机制进行了研究。结果表明,连接齐墩果酸后,配合物CycloIr-OA的抗癌活性有较大提升。CycloIr-OA富集在肿瘤细胞的线粒体中,导致活性氧产生,同时将细胞周期阻滞在S期,最终诱导肿瘤细胞坏死。  相似文献   

9.
芳(杂)环甾体化合物是一类具有显著生理活性的化合物,它们往往具有很好的抗菌、抗炎和抗肿瘤活性。本文根据此类化合物的结构类型进行分类,讨论近年来芳(杂)环甾体化合物的合成及生物活性研究进展,并对其发展趋势和应用前景进行了展望。  相似文献   

10.
烯烃活性聚合由于可以制备出预定分子量的窄分布聚合物,以及各种嵌段共聚物、末端功能化聚合物等而受到广泛关注.过渡金属催化的烯烃配位聚合反应活性高,催化剂性能可通过配体结构的修饰进行调节,聚合物微观结构易于调控,其活性聚合进一步拓展了对烯烃聚合物分子设计的手段,具有重要的意义.除了以钛、锆、钒等为金属中心的前过渡系催化剂之...  相似文献   

11.
分子中的环识别算法   总被引:1,自引:0,他引:1  
对于化合物结构自动解析系统来说,环的处理是必须的^[1~4],本文设计了环识别模块,该模块以从化合物的二维连接表出发,先获得化合物中的所有环,进一步得到最大环和最小环,并作为环约束,以增加ESESOC系统结构生成器的有效性。  相似文献   

12.
Abstract

The kinetics of Cr2+(aq) reductions of glycinato-, D,L-alanato, D,L-phenylalanato-, and D,L-leucinatobis-(ethylenediamine)cobalt(III) ions have been investigated. The rate law is of the form d(ln[Co(III)]/dt = k[Cr2+], where the rate constant k(M?1sec?1) and associated activation parameters δHδ(kcal mol?1 and δSδ (cal deg ?1mol?1) in parentheses, are respectively 1.65 · 0.06 (9.7 · 0.1, -25 · 1), 0.367 · 0.008 (10.9 · 04,-24 ·1), 0.529 · 0.021 (11.2 · 0.4, -22 · 1); and 0.358 · 0.019 (11.5 · 0.3, -22 · 1) at 298·K and ·[CIO·] = 1.0 M. The reactions are all inner-sphere.  相似文献   

13.
Fifteen of the bichromophore compounds containing oxazole or oxidation ring have been synthesized. Their structures have been identified by IR, 1H NMR spectra and elemental analysis. The UV spectra, fluorescence spectra and the laser conversion efficiencies have been determined . The results of determination show that the absorption and emission spectra Pf the bichromophore compounds are different from those of the corresponding single chromophore compounds.  相似文献   

14.
A simple transformation of 2‐alkylfurans and 2‐formylbenzoic acids into 4‐unsubstituted 3‐(3‐oxoalkyl)isocoumarins is described. It is based on the synthesis of 2‐(2‐carboxybenzyl)furans followed by their acid‐catalyzed recyclization to the target isocoumarins.  相似文献   

15.
When Ar is a low‐aromaticity homo‐ or heterosystem, the sulfonyl‐stabilized anion of nitrobutadienes 4 (which derive from the initial ring opening of 3‐nitrothiophene) undergoes a rather surprising addition onto the aromatic ring itself, thereby leading to the construction of an unusual eight‐membered sulfur heterocycle condensed with the original Ar ring. The competitiveness of such a pathway with respect to the formation of the thiopyran ring (i.e., addition onto the nitrovinyl moiety) is favored at low temperatures, thus revealing its nature as a kinetically controlled process.  相似文献   

16.
17.
For the last ten years, ring-shaped π-conjugated macrocycles possessing radially directed π-orbitals have been subject to intense research. The electronic properties of these rings are deeply dependent on their size. However, most studies involve the flagship family of nanorings: the cyclo-para-phenylenes. We report herein the synthesis and study of the first examples of cyclofluorenes possessing five constituting fluorene units. The structural, optical and electrochemical properties were elucidated by X-ray crystallography, UV-vis absorption and fluorescence spectroscopy, and cyclic voltammetry. By comparison with a shorter analogue, we show how the electronic properties of [5]-cyclofluorenes are drastically different from those of [4]-cyclofluorenes, highlighting the key role played by the ring size in the cyclofluorene family.  相似文献   

18.
For the last ten years, ring‐shaped π‐conjugated macrocycles possessing radially directed π‐orbitals have been subject to intense research. The electronic properties of these rings are deeply dependent on their size. However, most studies involve the flagship family of nanorings: the cyclo‐para‐phenylenes. We report herein the synthesis and study of the first examples of cyclofluorenes possessing five constituting fluorene units. The structural, optical and electrochemical properties were elucidated by X‐ray crystallography, UV‐vis absorption and fluorescence spectroscopy, and cyclic voltammetry. By comparison with a shorter analogue, we show how the electronic properties of [5]‐cyclofluorenes are drastically different from those of [4]‐cyclofluorenes, highlighting the key role played by the ring size in the cyclofluorene family.  相似文献   

19.
The AgI-promoted reaction of thiolactams with N-Boc amino acids yields an N-(α-aminoacyl) lactam that can rearrange through an acyl transfer process. Boc-deprotection results in convergence to the ring-expanded adduct, thereby facilitating an overall insertion of an amino acid into the thioamide bond to generate medium-sized heterocycles. Application to the site-specific insertion of amino acids into cyclic peptides is demonstrated.  相似文献   

20.
轮烯的合成及芳香性的研究   总被引:2,自引:0,他引:2  
李媛  孙晓云 《有机化学》1993,13(6):570-579
本文综述了近年来轮烯的合成及芳香性的研究进展,介绍了各种轮烯的一般合成方法。  相似文献   

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