Aurora激酶抑制剂ZM447439的合成及生物活性研究

目的优化Aurora激酶抑制剂ZM447439的合成路线,并对其体外生物活性进行评价。方法以4-羟基-3-甲氧基苯甲酸为起始原料,通过酯化、取代、硝化、还原、关环等反应合成ZM447439,涉及到的中间体及目标产物结构经1H-NMR,MS及IR确证。以MTT法研究其体外抗肿瘤活性(U937,K562,A549,LoVo及HT29细胞株),同时评价其体外AuroraA/B激酶抑制活性。结果合成了Aurora A/B激酶抑制剂ZM447439并进行相关生物活性研究。结论新合成路线总收率约34%,目标化合物具有较好的Aurora A/B激酶活性及肿瘤细胞增殖抑制活性。     

7-羟基双苄基丁内酯类木脂素的合成及抗炎活性研究简

目的合成7-羟基-α,β-二苄基-γ-丁内酯类木脂素并观察其抗炎活性。方法设计合成了15个目标化合物（7a-70）,结构经MS、1H-NMR确认。通过巴豆油致小鼠耳肿胀试验观察合成产物的局部用药抗炎活性。结果大部分目标化合物具有抑制小鼠耳肿胀活性,其中化合物7e活性最强,抑制率达60．5％,略好于阳性药吲哚美辛。结论目标化合物具有明显的抗炎活性,苯环上甲氧基和羟基的位置和数量对抗炎活性有影响,值得进一步研究。     

靶向组蛋白去乙酰化酶新型化合物的体外抗肿瘤活性筛选

目的针对组蛋白去乙酰化酶（HDAC）,自行设计合成系列化合物,着重对其体外抗肿瘤活性进行筛选,为进一步优化设计提供借鉴。方法首先利用MTT法测定各化合物对不同肿瘤细胞株增殖能力的影响,再对重点化合物进行组蛋白去乙酰化酶抑制活性测定。结果MTT结果显示,化合物H6和H99均显示出较好的肿瘤细胞增殖抑制效应;相应的HDAC活性检测表明,二者亦具有肯定的HDAC抑制效应。结论化合物H6和H99具有明显的体外抗瘤活性,值得深入研究。     

噻唑酰胺类化合物的合成设计

目的以乙酰唑胺为先导化合物,依据生物电子等排原理,设计并合成一类新型的噻唑酰胺类化合物类衍生物。方法以β-乙氧基丙烯酸乙酯、2,3,4-取代苯甲酸、对羟基苯甲酸为起始始料,经环合、酰化、亲核等反应合成目标化合物。结果合成了15个新型的噻唑酰胺类化合物,并对中间体和目标化合物进行了合成工艺研究。结论合成了15个目标化合物,为含单噻唑环的苯甲酰胺类化合物的合成设计打下了一定的基础。     

苯甲酰胺组蛋白去乙酰化酶抑制剂的合成及抗肿瘤活性

目的 设计合成苯甲酰胺嘧啶衍生物,并初步评价其抗肿瘤活性.方法 以4-氨甲基苯甲酸为原料经过4步反应,合成了12个苯甲酰胺衍生物,结构经过,HNMR和MS鉴定,采用MTT法筛选了目标化合物的抗肿瘤活性并进行初步评价.结果 合成了12个目标化合物,均未见文献报道.5个化合物显示较好的肿瘤细胞增殖抑制活性.结论 化合物5a...     

SU11274衍生物的合成及受体酪氨酸激酶抑制活性评价

目的 合成SU11274衍生物并对其进行受体PTK抑制活性评价.方法 合成了用乙二胺、1,3-丙二胺、1,2-丙二胺、1,6-己二胺替代SU11274哌嗪基团的4个SU11274新衍生物,结构经1H-NMR和ESI-MS验证.采用ELISA方法对这4个化合物进行了受体PTK抑制活性评价.结果 合成的4个SU11274衍...     

毛叶假鹰爪素C衍生物的合成与抗肿瘤活性评价

目的设计并合成出一系列Desmosdumotin C衍生物并考察其抗肿瘤活性。方法以2,4,6-三羟基苯乙酮为 原料合成一系列Desmosdumotin C衍生物,目标化合物经过1H-NMR、MS鉴定。采用SRB法对其抗肿瘤活性进行初步评价。结 果与结论设计并合成了 19个新化合物,初步的细胞活性实验表明,该系列衍生物大多具有肿瘤增殖抑制活性,且与先导物相 当,其中3个化合物显示出良好的抗肿瘤活性,为进一步对先导化合物Desmosdumotin C衍生物的结构优化奠定了一定的基础。     

含砜类结构的新型蛋白酪氨酸激酶抑制剂的合成与活性评价

目的以Ex-Rad为先导化合物,设计合成含有砜类结构的新型小分子蛋白酪氨酸激酶（PTK）抑制剂,并对其抑酶活性进行初步评价。方法以（对氯）氯苄为起始原料,通过亲核取代、氧化以及缩合反应合成目标化合物;采用酶联免疫法对目标化合物进行PTK抑制活性的测定。结果合成了3个含砜结构的目标化合物,结构经¹H-NMR确证。活性筛选结果表明,在浓度为100μmol·L^-1和1 mmol·L^-1时,目标化合物WT001的PTK抑制率分别为（3.5±1.7）%和（5.7±1.1）%,WT002抑制率分别为（50.6±2.7）%和（40.3±0.7）%,WT003抑制率分别为（33.7±3.1）%和（44.3±5.9）%,阳性药Ex-Rad的抑制率分别为（7.0±2.1）%和（35.4±4.1）%。结论在目标化合物中WT002和WT003显示出较强的PTK抑制活性,且活性高于同浓度的Ex-Rad。     

微波法合成酪醇衍生物及其抗氧化作用研究

目的设计、合成具有抗氧化、清除自由基作用的新型酪醇衍生物。方法以具有抗氧化作用的酪醇为先导结构,经结构修饰引入查尔酮结构单元增强其抗氧化、清除自由基作用。采用DPPH和FRAP法测定其体外抗氧化、清除自由基作用。结果采用微波合成反应,经邻位乙酰化、Claisen–Schmidt缩合以及水解3步反应高效制备了一系列含查尔酮结构单元的新型酪醇衍生物,所有化合物体外抗氧化、清除自由基活性均强于酪醇对照品。结论设计、合成并筛选可以得到一类新型酪醇衍生物。     

红景天苷衍生物的合成及其抗氧化作用研究

目的设计、合成具有抗氧化、清除自由基作用的新型红景天苷衍生物。方法以红景天苷元-酪醇为先导结构,经结构修饰引入查尔酮结构单元,增强其抗氧化、清除自由基作用。采用DPPH和FRAP法测定其体外抗氧化、清除自由基作用。结果采用微波合成反应,经邻位乙酰化、Claisen-Schmidt缩合以及水解3步反应,制备了一系列含查尔酮结构单元的新型红景天苷衍生物,所有化合物体外抗氧化、清除自由基活性均强于酪醇。结论设计、合成并筛选得到一类新型红景天苷衍生物,构效关系研究证实酚羟基和查尔酮结构单元是化合物抗氧化、清除自由基的重要结构特征。     

Syntheses and biological activities of novel 2-methoxyestradiol analogs, 2-fluoroethoxyestradiol and 2-fluoropropanoxyestradiol, and a radiosynthesis of 2-[(18)F]fluoroethoxyestradiol for positron emission tomography

INTRODUCTION: 2-Methoxyestradiol (2ME2) is an endogenous metabolite of the human hormone, estrogen, which has been shown to possess anti-tumor activity. 2-Fluoroethoxyestradiol (2FEE2) and 2-fluoropropanoxyestradiol (2FPE2), novel analogs of 2-methoxyestradiol, were designed and synthesized to be utilized as F-18 radiotracers for positron emission tomography (PET), with which the bio-distribution and intratumoral accumulations of 2ME2 could be measured in vivo for potential translation to human use. METHODS: 2FEE2 and 2FPE2 were synthesized from 3,17beta-estradiol in five steps respectively. Drug-induced microtubule depolymerization, antiproliferative activity against human cancer cell lines and HIF-1alpha down-regulation by 2FEE2 and 2FPE2 were investigated to examine whether these molecules possess similar anti-tumor activities as 2-methoxyestradiol. 2-[(18)F]Fluoroethoxyestradiol was synthesized for PET. RESULTS: Novel 2ME2 analogs, 2FEE2 and 2FPE2, were synthesized in 29% and 22% overall yield, respectively. 2FEE2 and 2FPE2 showed microtubule depolymerization and cytotoxicities against the human ovarian carcinoma cell line, 1A9, and the human glioma cell line, LN229. HIF-1alpha was down-regulated by 2FEE2 and 2FPE2 under hypoxic conditions. 2FEE2 was chosen as an F-18 radiotracer candidate, since it showed stronger antiproliferative activity than 2ME2 and 2FPE2. 2-[(18)F]Fluoroethoxyestradiol (2[(18)F]FEE2) was prepared in 8.3% decay-corrected yield in 90 min, based on a production of H[(18)F]F with more than 98% radiochemical purity. CONCLUSIONS: 2FEE2 and 2FPE2 showed similar activity as 2ME2. 2[(18)F]FEE2 was synthesized to be utilized as a PET radiotracer to measure the biological efficacy of 2ME2 and its analogs in vivo.     

Evaluation of radiopharmaceuticals sequestered by acutely damaged myocardium.

Eighteen radiopharmaceuticals were screened in a small-animal model as potential infarct-localizing agents. Twelve of the 18 compounds were labeled with 99mTc, four with 203Hg, one with 131I, and one with either 203Hg or 125I. The model used heat-induced myocardial lesions in the rat. The absolute concentration within the lesion and also the activity ratios of injured myocardium to normal heart tissue, blood, and muscle were determined for all compounds. Among the 99mTc-labeled agents, two bone-seekers [pyrophosphate (PPi) and 1-hydroxyethylidine-1,1-diphosphonate (HEDP)] showed the most promise; these were followed by 99mTc-tetracycline analogs and 99mTc-glucoheptonaate. The tracer showing the most favorable concentration in the lesion and the best target-to-nontarget ratios was an iodinated derivatives of hydroxymercurifluorescein labeled with either 125I or 203Hg. Consideration of the structure of these compounds suggests that the presence of mercury or of a polycyclic aromatic structure, such as that found is tetracycline and fluorescein, was associated with localization in damaged myocardial tissue. Mercury bound to such an aromatic moiety may produce an additive or even a synergistic effect.     

Molecular Simulation of Ligand‐Binding with DNA: Implications for 125I‐Labeled Pharmaceutical Design

Purpose: By using computer‐assisted molecular modeling software, to assess the effects of structural modification on the interaction of ¹²⁵I‐labeled iodoHoechst ligands and DNA and to design new analogs with specified distances between the Auger‐electron‐emitting ¹²⁵I atom and the DNA central axis.

Materials and methods: The Lamarckian genetic algorithm (AutoDock 3.0) was used to model the interaction between DNA and m‐iodo‐p‐methoxyHoechst (IMH), a ligand whose binding to the minor groove of DNA has been demonstrated (crystal structure) and which is available in the Protein Data Bank. m‐Iodo‐p‐ethoxyHoechst (IEH), a radioligand we had previously synthesized and characterized, was then docked onto DNA, the IEH–DNA complex minimized, and the binding free energy and inhibition constant (K_i) estimated and compared with those for IMH–DNA. Using the protocol, several novel iodoHoechst analogs (IH‐A and IH‐B) were designed. Finally, Insight II was used to measure the distances between the iodine atom (e.g. ¹²⁵I) of these Hoechst analogs and of 5‐iodo‐2′‐deoxyuridine (IdUrd) and the central axis of the targeted DNA, and these values were correlated with the expected/measured DSB yield following ¹²⁵I decay.

Results: The docking of IMH and DNA leads to a ligand–DNA complex approximately 1?Å RMSD (root mean square deviation) from the crystal‐structure position, and the IEH–DNA complex also has a small RMSD (1.27?Å). The distances between the ¹²⁵I atom and the DNA central axis are estimated as 8.61?Å for IMH, 9.20?Å for IEH and 5.7?Å for IdUrd. For the newly designed analogs, the distances from the ¹²⁵I atom to the central DNA axis are 10.92?Å for IH‐A and 16.39?Å for IH‐B.

Conclusion: These software programs can predict the reactivity of newly designed radiolabelled molecules with their targeted DNA molecules by molecular modeling prior to their chemical synthesis.     

Melanoma targeting with DOTA-alpha-melanocyte-stimulating hormone analogs: structural parameters affecting tumor uptake and kidney uptake.

Radiolabeled analogs of alpha-melanocyte-stimulating hormone (alpha-MSH) are potential candidates for the diagnosis and therapy of melanoma metastases. After our recent observation that a linear octapeptide alpha-MSH analog incorporating the metal chelator 1,4,7,10-tetraazacyclododecane-N,N',N',N'-tetraacetic acid (DOTA) at the C-terminal lysine, [Nle(4),Asp(5),d-Phe(7),Lys(11)(DOTA)]-alpha-MSH(4-11) (DOTA-NAPamide), showed high accumulation in melanomas in a mouse model, low uptake in normal tissues, and moderate uptake in the kidneys, we attempted to identify the structural parameters influencing tumor uptake versus kidney uptake. METHODS: We designed a series of novel DOTA-alpha-MSH analogs differing from DOTA-NAPamide by small alterations, such as the position of DOTA in the peptide, hydrophobicity, and charge, by modifying the C-terminal Lys(11) residue. They were evaluated both for their melanocortin type 1 receptor (MC1R)-binding potency and for their biodistribution by use of the B16F1 melanoma mouse model. RESULTS: When DOTA was shifted to the N terminus of the peptide, a 3-fold increase in kidney retention was obtained. However, when the epsilon-amino group of the Lys(11) residue was acetylated in addition to the DOTA relocation, kidney uptake returned to the low values obtained with DOTA-NAPamide; this result indicated that neutralization of the epsilon-amino group positive charge of the Lys(11) residue rather than the position of DOTA accounted for the low kidney retention. Unexpectedly, no further reduction in kidney uptake was obtained by the introduction of 1 or 2 negative charges on Lys(11). Melanoma uptake was in accordance with MC1R affinity; the highest values were obtained for peptides bearing carboxy-terminal amidation and positioning of DOTA. CONCLUSION: The kidney uptake of DOTA-alpha-MSH analogs could be considerably reduced, without affecting MC1R affinity, by altering (neutralizing) the charge of the Lys(11) residue. Accordingly, the resulting peptides exhibited a high ratio of tumor uptake to kidney uptake that is favorable for diagnostic and therapeutic applications. These structure-activity data may help to improve the performance of DOTA-alpha-MSH analogs and other radiopeptides.     

18F]Fluoro-beta-fluoromethylene-m-tyrosine derivatives show stereo, geometrical, and regio specificities as in vivo central dopaminergic probes in monkeys.

Stereo (D and L), geometrical (E and Z), and regiospecific (2-, 4-, and 6-[18F]fluoro) analogs of beta-fluoromethylene-m-tyrosine (FMMT) have been investigated in adult vervet monkeys (Cercopithecus aethiops sabaeus, n = 12) in vivo with positron emission tomography (PET). Brain transport through the blood-brain barrier and central aromatic amino acid decarboxylase (AAAD)-mediated decarboxylation rates were established. Results show strict structural dependency of the kinetic behavior of radiofluorinated FMMT analogs, with the E-isomer exhibiting a higher specificity over the (Z) geometrical counterpart for central dopaminergic structures. The 6-[18F]fluoro substituted L-(E)-FMMT was also favored over the 2- and 4-[18F]fluorosubstituted isomers in terms of their ability to localize in the same brain areas. The role of PET in drug development is also exemplified in this work.     

Effects of calcium antagonists on high-energy phosphates in ischemic rat brain measured by 31P NMR spectroscopy

The effects of various calcium antagonists on the ATP, PCr, and Pi levels as well as intracellular pH in normal and ischemic rat brain were examined by 31P NMR spectroscopy using a surface coil. None of the calcium antagonists tested showed any effect in the nonischemic rat brain. However, when global ischemia was induced by cardiac arrest, the ensuring rapid decrease of ATP and PCr and concomitant increase of Pi were significantly retarded by dihydropyridine calcium antagonists, but not by verapamil. The fall in pH caused by ischemia was not affected by either drug. Barbiturates showed effects similar to calcium antagonists, whereas calcium agonists showed the opposite. These results suggest that dihydropyridine calcium antagonists, similar to barbiturates, decrease the high-energy phosphate consumption of the brain, which might be beneficial in instances where their production is severely hampered, e.g., during ischemia.     

In situ radiotherapy with 111In-pentetreotide. State of the art and perspectives.

111In-pentetreotide (Octreoscan) and other radiolabeled somatostatin analogs are useful in the management of well differentiated neuroendocrine malignancies such as carcinoid or islet cell neoplasms. These radiopeptides bind to membrane bound somatostatin receptors (sst 1-5) which are over-expressed in a wide variety of neoplasms, especially those arising from the neuroectoderm. Imaging advances allow for the noninvasive determination of the presence of sst receptors by combining radioactivity [111Indium with a somatostatin analog, DTPA-D-phe1-octreotide (pentetreotide)]. Radiolabeled somatostatin analogs bind to membrane receptors and internalization of the complex occurs. Auger emitting somatostatin analogs offer a novel and significantly less toxic approach to controlling neoplastic diseases by delivering targeted radiation specifically to receptor bearing cells while sparing receptor negative cells. Responses of 62-69% in 85 patients with metastatic neuroendocrine tumors treated with high dose (6-19.6 GBq) 111In-pentetreotide, specifically targeting tumor somatostatin receptors, have been reported. Objective responses observed included biochemical and radiographic responses with prolonged survival. This article will discuss and review the multi-center data available to date, the mechanisms of action of radiolabeled somatostatin analogs, dosimetry, clinical response parameters, and toxicity.     

Peptide-based probes for cancer imaging

Receptors for regulatory peptides are overexpressed in a variety of human cancers. They represent the molecular basis for in vivo imaging with radiolabeled peptide probes. Somatostatin-derived tracers, designed to image the sst2-overexpressing neuroendocrine tumors, have enjoyed almost 2 decades of successful development and extensive clinical applications. More recent developments include second- and third-generation somatostatin analogs, with a broader receptor subtype profile or with antagonistic properties. Emerging tracers for other peptide receptors, including cholecystokinin/gastrin and GLP-1 analogs for neuroendocrine tumors, bombesin and neuropeptide-Y analogs for prostate or breast cancers, or Arg-Gly-Asp peptides for neoangiogenesis labeling, are also in current development. Application fields include both SPECT/CT and PET/CT.     

结合基因型耐药突变检测与表型耐药分析探索乙肝病毒耐药的新认识

核苷(酸)类似物是临床上治疗慢性乙型肝炎病毒(HBV)感染最常用的药物,但长期应用可引发病毒耐药,导致治疗失败。基因变异检测及表型耐药分析是发现和鉴定HBV耐药的基本方法,前者主要是应用基因测序或线性反向探针杂交等方法,检出已知的病毒耐药相关突变,后者则是在体外细胞水平确定携带有变异基因的HBV毒株对病毒复制力及核苷(酸)类药物敏感性的影响,是鉴定复杂与特殊HBV耐药变异的基本手段。我们通过技术创新,建立了敏感、特异、经济、高效的HBV基因型检测方法,进而建立了可靠的HBV复制力和表型耐药分析方法,广泛应用于临床样本分析,实现了对HBV耐药的早期发现及对新的非典型HBV耐药相关突变株的鉴定。我们近期在核苷(酸)类似物耐药和应答不佳的患者中检测到多种特殊和复杂HBV耐药相关突变,并结合临床资料,进一步对代表性变异株进行病毒复制力和表型耐药分析,取得了多项重要发现:①从大样本中检出和鉴定了多种多重耐药HBV变异株,并发现联合用药可协同抑制多重耐药HBV变异株的体外复制;②HBV rtL229替换可作为补偿变异,恢复拉米夫定耐药变异株rtM204I的病毒复制力;③rtM204Q是一种新的拉米夫定耐药相关突变;④rtA181C+rtL180M+rtM204V与恩替卡韦耐药相关;⑤同一耐药患者血清HBV虽检出耐药变异,但外周血单个核淋巴细胞(PBMCs)中的HBV cccDNA仍以原始野生株为优势种群,提示PBMCs为体内HBV野生株的"存储库",参与HBV肝外感染。上述发现对深入揭示HBV耐药变异的临床特点和发生机制,辅助临床合理制定并优化抗病毒治疗方案具有重要作用。     

Testosterone and Ca2+ regulation in skeletal muscle

The aim of this study was to examine the effect of testosterone treatment on the expression of dihydropyridine and ryanodine receptors in skeletal muscle of mouse. Furthermore, the effects of training, a method also known to elevate the plasma testosterone level, were studied and compared to the effects of pure testosterone administration. Male mice were either administered with testosterone or trained with treadmill. After 6 weeks, hindlimb muscles were excised and the expression of receptors was measured by Western blotting. Furthermore, the alterations in myosin heavy chain phenotypes were studied. In general, both training and testosterone administration induced changes in the expression of both receptors and in myosin heavy chain composition. In testosterone treated mice the expression of dihydropyridine receptor in extensor digitorum longus was higher compared to the control ones (38.9 %, p = 0.026). In soleus the expression was quite the contrary (- 27.3 %, p = 0.044), as was the case with ryanodine receptor (- 51.4 %, p = 0.012). The amount of ryanodine receptors was higher in rectus femoris (144.0 %, p = 0.044) and plantaris (48.1 %, p = 0.037) in testosterone treated mice. In trained mice, the expression of ryanodine receptor was significantly higher in gastrocnemius (27.6 %, p = 0.018), soleus (57.2 %, p = 0.025), plantaris (28.5 %, p = 0.009) and extensor digitorum longus (94.8 %, p = 0.009) than in the control ones. No differences were observed in the dihydropyridine receptor level. To conclude, training has a more important role in skeletal muscle adaptation compared to increased plasma testosterone level. However, in postural muscles both treatments have comparable effects.