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1.
超高交联吸附树脂柱色谱法分离提纯喜树碱及喜果甙   总被引:11,自引:0,他引:11  
本文比较了所合成的8种大孔超高交联吸附树脂对喜树果提取液中喜树碱和喜果甙的吸附性能及柱层析分离效果。结果表明,经超高效联树脂的层析分离,喜树碱的质量分数可提高到约15%,喜果甙的质量分数可提高到约60%。  相似文献   

2.
王立屏  魏永巨 《分析测试学报》2012,31(10):1282-1287
建立了薄层荧光扫描法测定中药喜树果中喜树碱和10-羟基喜树碱的方法.以无水甲醇为溶剂从喜树果样品中提取喜树碱和10-羟基喜树碱.在硅胶H板上以氯仿∶丙酮(7∶3)为展开剂可使喜树碱与10-羟基喜树碱很好地分离.以荧光激发波长350 nm线性扫描进行定量分析.在0.010 5~0.063 0μg范围内,喜树碱的积分荧光强度A与其质量m呈线性,相关系数为0.998,加标回收率为99%.在0.003 3 ~0.033 0 μg范围内,10-羟基喜树碱的积分荧光强度与质量呈线性,相关系数为0.999,加标回收率为96%.该方法简便,重复性好.以此方法测得喜树果样品中喜树碱和10-羟基喜树碱的含量分别为0.122%和0.013%.  相似文献   

3.
从喜树果中又分离出五种化学成分,用光谱及化学方法鉴定为11-羟基喜树碱(1),10-甲氧基喜树碱(2),脱落酸(3),丁香脂素(4)和β-谷甾醇.1为新生物碱,动物试验表明1,2均有明显的抗癌作用.  相似文献   

4.
喜树碱与胰蛋白酶的相互作用   总被引:1,自引:0,他引:1  
喜树碱(camptothecin,CPT)是从珙桐科乔木喜树中分离得到的一类重要抗癌药物,对动物肿瘤及白血病均有明显的抑制作用[1]。CPT分子为五环结构,含有一个吡咯[3,4-b]喹啉环,一个共轭吡啶环和一个α-羟基六元内脂环[2]。CPT通过嵌合抑制DNA拓扑异构酶Ⅰ的活性,对卵巢癌、结肠直肠癌  相似文献   

5.
新生物碱10-羟基脱氧喜树碱   总被引:4,自引:0,他引:4  
本文报道从羟基喜树碱的母液中分离剂, 新生物碱10-羟基脱氧喜树碱(1), 从园二色谱分析, 在天存在的A环氧取代喜树碱类化合物20-C具有和喜树碱一样的S构型, 而天然存在的脱氧喜树碱类化合物20C具有R构型, 即与喜树碱相反的绝对构型.  相似文献   

6.
3,5-二羟基-7,4′-二甲氧基二氢黄酮醇(1)从Cephalanthus spathelliferus中分离得到后[1], 又在Haplopappus bayahuen[2]和Lannea coromandelica[3]等植物中被发现, 在印度一直被用于治疗象皮病、阳痿、溃疡、阴道炎、口臭、痢疾和风湿病等. 3,5,7-三羟基-4′-甲氧基二氢黄酮醇(2)首次从Prunus donestica[4]中分离出来后, 又从Salix caprea L., Brazilian propolis中得到. 研究表明, 该化合物具有抗菌、抗肿瘤活性. 我们用与文献[5]类似的方法以2, 4, 6-三羟基苯乙酮和茴香醛为起始原料, 经选择性保护、缩合、环氧化、关环首次完成了化合物(±)-1和(±)-2的全合成. 合成路线如下:  相似文献   

7.
建立了改变检测波长测定喜树种子中喜树碱和 10 羟基喜树碱的高效液相色谱法。使用TechspheseODSC18(4.6mm× 2 5cm ,5 μm)色谱柱 ,以水∶乙腈 =3∶7(V/V)为流动相 ,流速为 1.0mL/min ,2 5℃下检测。检测波长 :0~ 8min时为 2 6 6nm ,8~ 2 0min时为 2 5 4nm。结果表明 :喜树碱的平均回收率为 10 0 .92 % ,RSD值 1.4 0 % ;羟基喜树碱的平均回收率为 10 0 .0 9% ,RSD值 1.34%。此方法简单、可靠。  相似文献   

8.
采用高速逆流色谱技术从马比木粗提物中快速分离制备喜树碱类化学成分。通过高效液相色谱测定各溶剂系统的分配系数,获得较好的分离条件。溶剂体系为:V(氯仿):V(正己烷):V(甲醇):V(水)=6:6:5:4,上相(水相)为固定相,下相(有机相)为流动相,正相洗脱;进样质量浓度:2.25 mg/mL;进样体积:20 mL;流速:2.0 mL/min;转速:800 r/min,从马比木粗提物中一次分离制备出3种单体成分。其结构经HPLC,UV,IR,ESI-MS和NMR确认和分析,分别为10-羟基脱氧喜树碱(1)、10-甲氧基喜树碱(2)和喜树碱(3),纯度分别为98.3%,99.3%,99.0%。  相似文献   

9.
通过硅胶和MCI柱色谱以及制备液相色谱等分离方法从白苞裸蒴中分离纯化得到6个含氮类化合物,经质谱和核磁共振等波谱技术将其结构分别鉴定为2-(1-羟基-6-甲氧基-4-氧亚基环己-2-烯-1-基)乙腈(1)、10-甲氧基-1-氧杂-3-氮杂螺[4.5]癸-2,6-二烯-8-酮(2)、2-(1-羟基-4-氧亚基环己-2,5-二烯-1-基)乙腈(3)、1-氧杂-3-氮杂螺[4.5]癸-2-烯-8-酮(4)、1-氧杂-3-氮杂螺[4.5]癸-2,6-二烯-8-酮(5)、对羟基苯乙腈(6).化合物1和2为新的含氮类化合物,化合物3为新的天然产物,其余化合物均为首次从该植物中分离得到.  相似文献   

10.
3,5 -二羟基 - 7,4′-二甲氧基二氢黄酮醇 ( 1 )从 Cephalanthus spathelliferus中分离得到后 [1] ,又在H aplopappus bayahuen[2 ] 和 L annea coromandelica[3] 等植物中被发现 ,在印度一直被用于治疗象皮病、阳痿、溃疡、阴道炎、口臭、痢疾和风湿病等 . 3,5 ,7-三羟基 - 4′-甲氧基二氢黄酮醇 ( 2 )首次从 Prunusdonestica[4 ] 中分离出来后 ,又从 Salix caprea L.,Brazilian propolis中得到 .研究表明 ,该化合物具有抗菌、抗肿瘤活性 .我们用与文献 [5 ]类似的方法以 2 ,4,6-三羟基苯乙酮和茴香醛为起始原料 ,经选择性保护、缩合、…  相似文献   

11.
云南褐煤蜡氧化精制的研究   总被引:5,自引:1,他引:4  
本工作对云南潦浒、寻甸、昭通蒙旦蜡进行了脱树脂,氧化精制研究,探索国产蒙旦蜡能否经精制后满足合成改性浅色蜡的要求。实验结果表明,潦浒、寻甸两厂生产的蒙旦蜡经氧化精制不能达到完全脱色,而昭通蒙旦蜡在相同的精制条件下极易脱色,所得浅色蜡质量达到和超过国外同类产品的水平,因此昭通蒙旦蜡是生产浅色蜡的理想原料。在精制反应中,加入适量YPSO-1添加剂,对改善反应条件,产物的分离,提高得率和质量均有良好的影响。文中还讨论了潦浒、寻甸脱脂蜡经氧化精制不能完全脱色的原因  相似文献   

12.
甲基丙烯酸十二酯精制及其树脂性能研究   总被引:1,自引:0,他引:1  
对工业级甲基丙烯酸十二酯单体进行了精制提纯,采用悬浮聚合法合成了甲基丙烯酸十二酯树脂。利用傅立叶变换红外光谱(FTIR)对精制前后单体以及树脂的结构进行了表征、利用热分析仪(TG)和差式扫描量热仪(DSC)对树脂的热性能进行了分析,同时研究了精制时碱液浓度对树脂饱和吸油率、吸油速率以及充分溶胀后树脂剩余率的影响。结果表明,精制后单体合成的树脂耐热性能有了明显改善,热降解温度大大提高;精制前后单体合成的树脂,由于杂质存在的缘故,其低温玻璃化转变类型明显不同;经6wt%碱液和8wt%碱液精制后单体的纯度有了明显提高,由其合成的树脂饱和吸油率,吸油速率都有较大提高,甚至接近化学纯单体合成树脂的饱和吸油率。  相似文献   

13.
利用^13CNMR数据证实了在低磺化剂用量下脲醛树脂的磺化改性仍可发生,并对磺化脲醛(SUF)树脂制备过程中的羟甲基化、缩合、磺化及缩聚等各步反应机理进行了探讨.明确了SUF树脂的^13CNMR谱图中各峰位所对应的结构单元,认为3个未知峰的出现与磺化改性得到的一些新结构单元有关,并对它们的结构进行了推测.通过对比不同磺化和缩聚反应程度下得到的SUF产物的^13CNMR数据,对磺化和缩聚反应后某些结构的出现和消失进行了解释.  相似文献   

14.
The solubilization of tributylphosphate (TBP), a polar oil, in various micellar solutions of Pluronic has been investigated by (1)H NMR spectroscopy. Partial phase diagrams of the three components systems (Pluronic-TBP-water) have shown two characteristic temperatures, called CPT and SMT, which control the phase behavior (see Part I); Both temperature depend on the copolymer structure and, interestingly, are directly related to the TBP concentration in the medium. Monophasic microemulsions are observed only when the temperature ranges between the SMT and the CPT. Moreover, the evolution of the CPT with the TBP content clearly indicated the occurrence of a structural change of the microemulsions which allows higher quantities of TBP to be solubilized. In this second part, (1)H NMR studies of TPB/micellar systems have essentially focused on elucidating the nature of the interactions between TBP and micelle, or on the location of the solubilized species, mainly from the dependence of chemical shifts or linewidths on TBP concentration. Especially, the NMR spectra of the microemulsions before and after the structural change have been compared with those obtained for pure solution of Pluronic in D(2)O at different temperatures and in CDCl(3). The analysis of the (1)H NMR chemical shifts suggests a structural transformation of the TBP-Pluronic micelles in the sense of an hydrophobic TBP-PPO core becoming more and more dense as the TBP concentration increases. Especially, (1)H NMR data evidence an evolution of the hydration state of the hydrophobic core following addition of TBP in the micellar solutions. During the addition of TBP, the microemulsion structure turns from spherical swelled micelles to nanodroplets of pure TBP stabilized by the Pluronic (pure nanophase of TBP stabilized by the copolymer). It is shown that the structural change strongly depends on the temperatures (CPT and SMT, see Part I) and on the copolymer structure.  相似文献   

15.
手性仲丁胺的制备拆分和光学纯度的测定   总被引:4,自引:0,他引:4  
为了获取仲丁胺的两种光学纯对映异构体,采用D-或L-酒石酸作为拆分试剂, 经过多次结晶,分别得到S-(+)-仲丁胺·乙-(+)-酒石酸盐和R-(-)-仲丁胺·D-(-) -酒石酸盐晶体,从而成功实现了其分离.产物的光学纯度通过用光活性(R)-联萘 酚磷酰氯衍生成(R)-联萘酚磷酰胺后,经^31P NMR测定,o_p_>99%,拆分剂D-或 L-酒石酸经过强酸型阳离于交换树脂(001×7×7型)方便回收,回收率>80%.  相似文献   

16.
Amphiphilic block copolymers, methoxy poly(ethylene glycol)-b-poly(valerolactone) (mPEG-b-PVL), were synthesized via ring opening polymerization of δ-valerolactone in the presence of methoxy poly(ethylene glycol) (mPEG). The copolymers form micelle-like nanoparticles by their amphiphilic characteristics and their structures were examined by Nuclear Magnetic Resonance (NMR). The sizes of nanoparticles ranged from 60 to 120 nm as measured by dynamic light scattering detection, and were larger with higher molecular weight of the copolymers. The Critical Micelle Concentration (CMC) of these nanoparticles in water decreased with increasing molecular weight of hydrophobic segment. Stability analysis showed that the micellar solutions maintain their sizes at 37 °C for six weeks without aggregation or dissociation. The lyophilization method was better than the evaporation method when camptothecin (CPT) was incorporated to the micelles. The former method yielded higher CPT loading efficiency and lower aggregation. The loading efficiency of CPT could be more than 96% and a steady release rate of CPT was kept for twenty six days. Moreover, the mPEG-b-PVL polymeric micelles offered good protection of CPT lactone form at 37 °C for sixteen days. The copolymers showed no cytotoxicity towards L929 mouse muscular cells when incubated for one day. Taken together, the mPEG-b-PVL copolymer has potential to be used for the delivery of CPT or other similar drugs.  相似文献   

17.
We present here a novel camptothecin (CPT) prodrug based on polyethylene glycol monomethyl ether‐block‐poly(2‐methacryl ester hydroxyethyl disulfide‐graft‐CPT) (MPEG‐SS‐PCPT). It formed biocompatible nanoparticles (NPs) with diameters of approximately 122 nm with a CPT loading content as high as approximately 25 wt % in aqueous solution. In in vitro release studies, these MPEG‐SS‐PCPT NPs could undergo triggered disassembly and much faster release of CPT under glutathione (GSH) stimulus than in the absence of GSH. The CPT prodrug had high antitumor activity, and another anticancer drug, doxorubicin hydrochloride (DOX ? HCl), could also be introduced into the prodrug with a high loading amount. The DOX ? HCl‐loaded CPT prodrug could deliver two anticancer drugs at the same time to produce a collaborative cytotoxicity toward cancer cells, which suggested that this GSH‐responsive NP system might become a promising carrier to improve drug‐delivery efficacy.  相似文献   

18.
Highly flexible, optically transparent epoxy resin/cellulose composites were prepared by using the solution impregnation method firstly and then thermal cured. The composite contained 60 wt% resin was still mechanically stable and flexible, and it integrated the merits of cellulose and resin, but the highly hydrophilic behavior of cellulose has been reduced. Contact angle measurements with water demonstrated that the composite films had obvious hydrophobic properties, and a decrease in the water uptake and the permeability towards water vapor gas was also observed. The transmittance of the composite films at 550 nm was about 85–88 %. The thermal and mechanical properties of the composite films were improved. Moreover, the composite films could be used in UV imprint lithography for circuit, and the definition could be compared with that of widely used glass plate.  相似文献   

19.
磁性离子交换树脂连续化运行条件的研究   总被引:4,自引:0,他引:4  
本文针对现行离子交换操作过程和离子交换树脂的不足,研制出一种新磁性离子交换树脂,并对其应用于连续化子离子交换过程的运行条件进行了较详细的研究,结果表明,磁性离子交换树脂应用于连续化操作过程,可增大操作流速或提高工作效率。  相似文献   

20.
用ICP-AES研究了含硫氮螯合树脂对碱性氰化溶液中金、银、铜、铁、锌等金属离子的吸附行为。结果表明,该树脂除定量吸附金、银的氰化物外,也吸附铜、锌、铁的氰化物;吸附在树脂上的银及其它贱金属离子可以用2%NaCN定量解吸,用硫脲-硫酸溶液可顺利地将金从树脂上洗脱下来,由此可实现金与银等元素的分离。树脂重复使用性能良好。对该树脂吸附金属氰化物的机理进行了初步探讨。  相似文献   

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