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1.
新型金属卟啉的合成及其对大肠杆菌生长代谢的抑制作用   总被引:13,自引:1,他引:12  
以5,10,15,20-四(对羟基苯基)卟啉(2)为原料,合成并表征了一系列 水溶性和非水溶性的金属卟啉。使用LKB 2277热活性监测器测定了大肠杆菌在金属 卟啉4a ~ 4f和7a ~ 7f作用下的生热曲线,得到了不同金属卟啉在不同浓度下大 肠杆菌生长代谢的生热速率常数k,最大发热功率p_(max)和最大发热功率的出现时 间t。结果发现,含有吡啶溴化盐的水溶性金属卟啉7a ~ 7f对大肠杆菌生长代谢 的抑制活性要明显大于含有酯基的金属卟啉4a ~ 4f。  相似文献   

2.
合成了1种含四氯合钴配阴离子的4-氯苄基吡啶季铵盐[4-ClBzPy]2[CoCl4];利用元素分析仪、X射线单晶衍射仪以及紫外光谱仪和红外光谱仪等分析了其组成、晶体结构及光谱学性质;利用电导仪测定了[4-ClBzPy]2[CoCl4]的电导,并检测了其对金黄色葡萄球菌和大肠杆菌的抗菌活性.结果表明,合成的[4-ClBzPy]2[CoCl4]季铵盐为单斜晶系,P2(1)/c空间群,晶胞参数为a=0.769 5(13)nm,b=1.895 1(3)nm,c=0.946 3(15)nm,β=93.183(2)°,V=1.378 0(4)nm3,Z=2,Dc=1.470g/cm3,GOOF=1.007,R1=0.041 8,wR2=0.100 2.与此同时,季铵盐[4-ClBzPy]2[CoCl4]对金黄色葡萄球菌和大肠杆菌均具有较好的抗菌活性.  相似文献   

3.
通过对大黄素的C6位进行化学修饰, 设计合成了7个含氮杂环的大黄素衍生物和3个含季铵盐基团的大黄素衍生物. 通过红外光谱、 1H NMR和质谱表征了所制备化合物的结构, 并测试了它们对白血病细胞Molt-4和淋巴瘤细胞CA46的体外抑制活性. 其中化合物8, 9a+9b, 20a, 20b和20c均显示出比大黄素更高的抗癌活性, 表明苯并咪唑基团和季铵盐基团是大黄素提高抗癌活性的有效药效团.  相似文献   

4.
新型金属卟啉的合成及其仿酶活性研究   总被引:19,自引:0,他引:19  
合成并表征了一系列水溶性和非水溶性金属卟啉3a~3e,5a~5f和8a~8f;测试了这些金属卟啉作为超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的模拟物催化歧化O2-和催化分解H2O2等有毒氧自由基的活性及抗脂质过氧化性质.结果表明,含有吡啶溴化盐的水溶性金属卟啉8a~8f的仿酶活性明显大于含有羟基的非水溶性金属卟啉3a~3e和含有酯基的金属卟啉5a~5f.  相似文献   

5.
合成了7个大黄素季铵盐、2个芦荟大黄素季铵盐、1个水溶性大黄素季铵盐和1个α-萘酚醌苯基甲烷季铵盐化合物,并测试了其抗癌活性.含有1条长碳链的大黄素季铵盐的抗癌活性很低,但是含有2条长碳链的大黄素和芦荟大黄素季铵盐的抗癌活性较好.用亲水性的长链替代季铵盐中亲脂性的长碳链会导致大黄素季铵盐失去抗癌活性.α-萘酚醌苯基甲烷季铵盐显示了中等的抗癌活性,表明在具有电子传递能力的分子中引入亲脂性的长碳链季铵盐可以增加其抗癌活性.  相似文献   

6.
鉴于前期研究发现的源于D-核糖的苯并咪唑并氮杂糖1和2具有良好的β-葡萄糖糖苷酶抑制活性,通过关键的Mitsunobu反应,设计合成了系列新型L-核糖源和2-脱氧-D-核糖源的苯并咪唑并氮杂糖衍生物6a~6c和7a~7c;并依据电子等排的药物设计方法,设计了系列新的糖环上2位氨基取代的稠合三环氮杂糖13a、13b和17a~17e;以及4位烷氧基取代的氮杂糖28a和28b.化合物13a和13b通过苄胺对甲磺酰化的羟基(OMs)取代合成,化合物17a~17e通过氨基对三元环氧中间体15的开环制备,化合物28a和28b通过4-羟基对卤代烃的亲核取代合成.测试了化合物6a~6c、7a~7c、13a、13b、15、17a~17e、19、28a和28b对α-葡萄糖糖苷酶(黑曲霉)、β-葡萄糖糖苷酶(杏仁)和α-半乳糖糖苷酶(咖啡豆)的抑制活性,结果显示所测化合物在10μmol/L时对α-葡萄糖糖苷酶和α-半乳糖糖苷酶没有或微弱的抑制活性,部分化合物表现出较好的β-葡萄糖糖苷酶抑制活性,其中环氧中间体15和2-氨基化合物17a活性最好,IC50值分别为10.5和11.7μmol/L,但均低于阳性对照品1的活性.结果表明该类稠合三环氮杂糖是一类良好的选择性β-葡萄糖苷酶抑制剂.  相似文献   

7.
新型易降解的季铵盐型Gemini表面活性剂的合成   总被引:1,自引:0,他引:1  
N,N-二甲基丙二胺与脂肪酸(癸酸、月桂酸或肉豆蔻酸)反应制得长链酰胺(3a ~ 3c);3与1,4-二溴丁烷反应合成了新型易降解的季铵盐型Gemini表面活性剂(1a ~1c),其结构经1H NMR和IR表征.测试结果表明,1具有极低的临界胶团浓度、较强的乳化和增溶能力.  相似文献   

8.
在[(Py)4Co(HCrO4)2]存在下,吡啶叶立德、喹啉叶立德或异喹啉叶立德分别和1,4,4a,8a-四氢-1,4-桥亚甲基萘-5,8-二酮反应,一步法合成了中氮茚类多环化合物(1a~1c,2a~2b,3).该方法原料易得,反应条件容易控制,为合成这类化合物提供了新方法.  相似文献   

9.
裴蕾  张桂玲  尚岩孙  翠翠  甘甜 《物理化学学报》2016,32(10):2495-2502
利用密度泛函理论和非平衡格林函数的方法对硅桥调控后的聚茂钒体系([V(Cp)2(SiH2n]mn=1(a),n=2(b),n=3(c);m=∞;Cp=环戊二烯基))的电子结构和输运性质进行了研究。研究结果表明:随着硅桥的增长,V-V的铁磁性耦合变弱而反铁磁性耦合增强。a和b证实为铁磁性基态,而c更倾向为反铁磁性基态。a和b的铁磁性基态中的每个钒原子的磁距为3.0μB,超过钒-苯络合物或者纯聚茂钒体系的3倍。a-c的输运性质同它们的电子结构相一致,导电性变化规律为c > b > a。对于a和b,自旋向下状态的导电性略强于自旋向上状态。a和c都发生了明显的负微分电阻效应而b却没有,这主要是由于两个二茂钒的排列取向不同:a和c(SiH2为奇数)中二茂钒呈V-型取向排列,进而导致了类似于离子键的量子点耦合,而b(SiH2是偶数)中二茂钒是平行-型取向排列,从而导致了类似于共价键的量子点耦合。此外,由于散射区和两个电极之间的不对称耦合,a-c的导电性对电压施加方向较敏感。  相似文献   

10.
聚酰胺-胺型树枝状高分子PAMAM溶液的特性粘度   总被引:6,自引:0,他引:6  
测定了树枝状高分子PAMAM(聚酰胺-胺型,乙二胺为内核)及其季铵盐在水溶液中的特性粘度[η].结果表明,PAMAM的[η]在代数G=2~3处有最大值,而其季铵盐则在此处有最小值.同时发现高分子的流体力学等效圆球半径Rη随G增大近似线性增长.通过对PAMAM及其季铵盐特性粘度的研究,揭示了不同代数高分子结构形态的变化规律.  相似文献   

11.
细胞动力学研究IV.细菌非理想生长过程的热动力学   总被引:3,自引:1,他引:3  
By using LKB2277 Bioactivity Monitor, we have determined the thermogenesis power curves of four kinds of bacteria: Brucella M5(55010), 83-980, 83-981 and E. coli. We have also derived the thermokinetic equation for the process of bacterial growth, which was untypical "S" , unideal growth, as:
Ln[P•(1-P/Pm)?-1]=ln[P0•(1-P0/Pm)?-1]+kt
From this equation, the rate constants of bacterial growth k wore obtained. This thermokinetic equation is very suitable for cell growth of separated culture, in which the thermogenesis curve is untypical. The model propoted by equationl(1) has been compared with the exponential and logistic models. This thermokinetic equation is very significant for the study of bacterial limited growth and their characteristics.  相似文献   

12.
Using microcalorimetric method, the thermally measured curves of different types of metabolism of E. coli were determined. From these thermal measured curves, we can obtain the heat output of E. coli at growth metabolism to be 1 .74+10.63 pW.cell- 1; and0.14+0.04 pW.cell-1 at the non-growth metabolism while at the endogenous metabolismit is 0.045+0.001 pW﹒cell-1  相似文献   

13.
从中药粉防己中提取粉防己碱。 在无水乙醇中粉防己碱分别与M(NO3)2·3H2O(M=Cu,Zn,Co,Ni)反应,合成了4种新的金属配合物,其结构分别用FT-IR和UV等测试技术进行了表征。 应用微量量热仪分别测定了不同浓度的粉防己碱及4种粉防己碱的金属配合物、M(NO3)2·3H2O(M=Cu,Zn,Co,Ni)对大肠杆菌代谢作用的热功率-时间曲线,运用Logistic方程计算出细菌的生长速率常数,建立了生长速率常数与药物浓度间的关系,进而确定了最佳抑菌浓度。 结果表明,4种金属配合物的抑菌作用均比M(NO3)2·3H2O和粉防己碱强。  相似文献   

14.
生物热动力学研究——大肠杆菌生长速率和激活能   总被引:5,自引:4,他引:5  
大肠杆菌生长的全热谱已被测定,再进一步根据其指数生长期的热谱信息,确定了它的生长速率和激活能。在指数生长期,细菌数按指数规律增加,可用下式表示:n_t=n_0e~(kt)(1)式中:t为指数生长期开始后的某一时间,n_0,n_t分别为指数生长期开始时和t时的细菌数,k为生长速率常数。因此,同期细菌输出的热功率也是按指数规律同步增长。可表示为:  相似文献   

15.
Zhang S  Wei W  Zhang J  Mao Y  Liu S 《The Analyst》2002,127(3):373-377
The effect of magnetic field on the growth of bacteria was studied with the series piezoelectric quartz crystal (SPQC) sensing technique. The growth situations of Escherichia coli (E. coli) in the absence and presence of different intensities of static magnetic fields were examined and analyzed. The results showed that the growth of E. coli was inhibited due to the presence of magnetic fields. By fitting frequency shift (deltaD) versus time curves according to the frequency shift response equation of SPQC, the relationships between three kinetic growth parameters, i.e., the asymptote A, the maximum specific growth rate mu(m) and lag time lambda, and magnetic field intensity were established. Based on these results, a new response model containing the magnetic field intensity was derived as: delta(f) = 167.7 (7.25 - 7.11B)/[1 + exp[4 x 2.46e(-3.97B)/(7.25 -7.1 IB)] x (4.42 + 16.46B - t) + 2]] The kinetic parameters of bacterial growth obtained from this model are close to those obtained from the logistics popular growth model, in which the concentration of the bacteria was determined by the traditional pour plate count method.  相似文献   

16.
In this study, the effects of Benzoinum and Styrax on Escherichia coli (E. coli) growth were investigated by microcalorimetry. Using a TAM Air Isothermal Calorimeter, ampoule method, the power-time curves of E. coli growth at 37°C affected by Benzoinum and Styrax were measured. By analysing some quantitative thermokinetic parameters, such as growth rate constants k, the maximum heat-out power Pm, the time of the maximum heat-out power tm, the total heat production Qt and inhibitory ratio I, one could find that low concentrations (0-3.9 mg mL(-1)) of Benzoinum and Styrax had stimulation effects on E. coli growth, and high concentrations (7.8-125.0 mg mL(-1)) of these two drugs would inhibit the growth of the bacteria. The antibacterial effects of Benzoinum and Styrax can also be expressed as half inhibitory concentration IC50. The IC50 values for Benzoinum and Styrax are 78.5 and 88.0 mg mL(-1), respectively, which suggests that the antibacterial effect of Benzoinum on E. coli was much stronger than that of Styrax. This study provides a useful method to investigate the effects of herbal medicines on microbes. It also supplies some references for the application of Benzoinum and Styrax in clinical treatment.  相似文献   

17.
用微量热法测定了两种头孢菌素头孢哌酮钠(CFZ)和头孢哌酮钠舒巴坦钠(CFZ-SBT)在37 ℃时对大肠杆菌DH5α代谢作用的影响. 根据产热曲线分别获得了大肠杆菌DH5α在不同浓度的头孢哌酮钠和头孢哌酮钠舒巴坦钠作用下的生长速率常数(k)、抑制率(I)、最大产热功率(Pm)以及最大产热功率所对应的时间tm等热动力学参数. 研究结果表明, 头孢哌酮钠和头孢哌酮钠舒巴坦钠对大肠杆菌的致死量分别为0.1和0.25 μg/mL. 通过研究k, I, Pm, tm和浓度(c)间的关系发现, 舒巴坦钠的加入没有增加头孢哌酮钠对大肠杆菌DH5α的抑制作用.  相似文献   

18.
Since Schiff base and its metal complexes are of antibacterial and anticancer bioactivity, it has been a research subject of much interest. It is reported that Cu(Ⅱ)-SG could inhibite the synthesis of O2- markedly and could also combine with the salmn sperm DNA. The paper repored that by using microcalorimetric method The growth meloabolism of E.coli at different temperature and reacted upon by Cu(Ⅱ)-SG. The power-time curves of E.coli reacted with Cu(Ⅲ)-SG at different temperature has been determined by LKB2277 Microcalorimetric Monitor and the multiplication rate constant k, generation time G,bacterial growth inhibition ratio I,total thermogenetic quantity Q, the heat quantity of a single bacterium. Q0 and the heat quantity of a single bacterium per minute Q0 have also been calculated. On the basis of k~T data, the formula Lnk~1/T has graphically obtained and activation energy Ea and pre-exponential factor A have been calculated. According to the parameters of the growth metabolism of E.coli,some linear relationships have been derived. The paper provides a discussion about the growth metabolism of E.coli reacted upon by Cu(Ⅱ)-SG at different temperature, and it is found that、and tr can be used to characterize bacterial growth metabolism and the antibacterial activity of Cu(Ⅱ)-SG at different temperature.  相似文献   

19.
The superoxide (O2-.) production in Escherichia coli through the action of benzofurazans (BZs) was examined using the cytochrome c (cyt. c) reduction method. Adding BZs to E. coli cell suspensions caused the cyt. c reduction, which was completely inhibited by superoxide dismutase (SOD). The effects of BZs on cyt. c reduction was in the order of benzofurazan (1) approximately 4,7-dimethylbenzofurazan (2) approximately 4,7-dibromobenzofurazan (3) less than 4-bromo-6-cyanobenzofurazan (4) less than 4,7-dicyanobenzofurazan (5). This was correlated with the toxicity of BZs against E. coli growth (1 approximately 2 approximately 3 less than 4 less than 5) and with the redox potentials of BZs (1 approximately 2 less than 3 less than 4 less than 5). The formation of compound 5 anion radical in the cell suspensions in the absence of dioxygen (O2), was determined using ESR spectrum. The ESR signal of the anion radical disappeared with the addition of O2. The BZs effected the O2-. production in E. coli cells.  相似文献   

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