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1.
New thiazole derivatives were synthesized and fully characterized, then coordinated with PtCl4 salt. Also, the newly synthesized Pt(IV) complexes were investigated analytically (elemental and thermogravimetric analyses), spectrally (infrared, UV–visible, mass, 1H NMR, 13C NMR, X‐ray diffraction) as well as theoretically (kinetics, modeling and docking). The data extracted led to the establishment of the best chemical and structural forms. Octahedral geometry was the only formula proposed for all complexes, which is favorable for d6 systems. The molecular ion peaks from mass spectral analysis coincide with all analytical data, confirming the molecular formula proposed. X‐ray diffraction (XRD) and scanning electron microscopy (SEM) allowed discrimination of features between crystalline particles and other amorphous morphology. By applying Gaussian09 as well as HyperChem 8.2 programs, the best structural forms were obtained, as well as computed significant parameters. Computed parameters such as softness, hardness, surface area and reactivity led us towards application in two opposing pathways: tumor inhibition and oxidation activation. The catalytic oxidation for CO was conducted over PtO2, which was yielded from calcination of the most reactive complex. The success of catalytic role for synthesized PtO2 was due to its particulate size and surface morphology, which were estimated from XRD patterns and SEM images, respectively. The antitumor activity was tested versus HCT‐116 and HepG‐2 cell lines. Mild toxicity was recorded for two of the derivatives and their corresponding complexes. This degree of toxicity is more favorable in most cases, due to exclusion of serious side effects, which is coherently attached with known antitumor drugs.  相似文献   
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Bryostatins are a class of naturally occurring macrocyclic lactones with a unique fast developing portfolio of clinical applications, including treatment of AIDS, Alzheimer's disease, and cancer. This comprehensive account summarizes the recent progress (2014–present) in the development of bryostatins, including their total synthesis and biomedical applications. An emphasis is placed on the discussion of bryostatin 1 , the most-studied analogue to date. This review highlights the synthetic and biological challenges of bryostatins and provides an outlook on their future development.  相似文献   
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Thetrans-[Pt(NC5H4C(O)NHC2H4ONO2)2Cl2] complex (2) was prepared by the reaction of nicorandyl (N-nitroethoxynicotinamide), which is widely used in cardiology, with K2PtCl4 in water. The structure of2 was established by X-ray structural analysis. It was found that complex2 exhibits high antitumor activity, in particular, antimetastatic activity, unlike the analogous CuII complex with bromine atoms. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1672–1675, September, 1997.  相似文献   
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Over the last two decades many strategies have been planned to design specific drugs for rare diseases to target their action at the DNA level. Advancements in our understanding of the interactions of small nonpeptide molecules with DNA have opened the doors for “rational” drug design. Special methods have now been developed to give accurate account of the precise location of ligand-DNA adducts on target DNA. We are now in a position to think of designing ligands that recognize particular sequences of base pairs. This work will allow us to enter into a new era of gene therapy for diseases like Cystic fibrosis, Alzheimer’s disease and many related disorders at genetic level. These ligands can also be employed in the treatment of various types of cancers. They may also be useful as highly specific probes to locate particular sequences in the genomic DNA.  相似文献   
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新马兜铃内酯的晶体结构   总被引:1,自引:0,他引:1  
从绵毛马兜铃的根茎中分离出一种新的倍半萜内酯, 它的分子式由高分辨质谱数据确定为C~1~5H~2~0O~2, 它的结构用单晶X射线衍射法测定, 晶体属三斜晶系, 空间群为P1, a=0.6275(3)nm, b=0.8057(4)nm, c=1.3622(6)nm; α=88.78(4)°,β=91.44(4)°, γ=105.20(4)°; Z=2.3107。  相似文献   
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低氧条件下,钴(Ⅲ)的氮芥配合物具有合适的还原电位,就可能还原得到比较活泼的Co(Ⅱ)配合物,在溶液中其活性配体很快被体内的小分子取代,释放出的活性配体可以杀死低氧区内外的癌细胞,因此筛选合适的钴配合物作为低氧选择性抗癌药物的研究很有意义。本文以双 (2 氯乙基)胺(简称BCA)为活性配体,取代乙酰丙酮为辅助配体,合成一系列Co(Ⅲ)配合物(下图)。初步评估结果表明,其中两个配合物具有一定的低氧选择性,配合物的还原电位对药物的低氧选择性影响很大,合适的还原范围可能比较窄。1 实验部分1.1 试剂与仪器按文献[1]的方法合成…  相似文献   
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吉西他滨是临床一线治疗恶性肿瘤的药物,但其4-位氨基(N4)易与脱氧胞苷脱氨酶(CDA)作用而失活,导致代谢稳定性差,严重影响了临床治疗效果。以吉西他滨为起始原料,经3步反应合成了N4保护的脂溶性吉西他滨衍生物(3a和3b),其结构经1H NMR,13C NMR和HR-MS(ESI)表征。体外活性测试结果显示:化合物3a对多种肿瘤细胞的抗增殖作用均强于临床药物吉西他滨(P<0.05)。酶稳定性实验结果表明:3a几乎不受CDA影响,代谢稳定性显著高于原药吉西他滨。  相似文献   
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