汉防己甲素衍生物的合成及其生物活性

为寻找更为有效的抗肿瘤药物,改善汉防己甲素的抗肿瘤活性,本文以汉防己甲素为原料,经过Suzuki反应设计并合成了6个新的双苄基异喹啉类衍生物。新化合物经过质谱(MS)、核磁共振氢谱(~1H NMR)、核磁共振碳谱(~(13)C NMR)等技术手段进行了结构确证。采用细胞计数试剂盒(CCK-8)法初步评价了6个新化合物对人肺癌细胞(A549)和小鼠白血病细胞(P388)的抗肿瘤活性。结果表明,化合物均有不同程度的抗肿瘤活性,其中化合物H1、H4、H6对A549细胞的抗肿瘤活性(IC5010μmol/L)明显优于阳性对照汉防己甲素。     

广防己挥发油的GC-MS指纹图谱研究

防己药材主要分粉防己和木防己两类,木防己包括广防己和汉中防己。广防己为马兜铃科植物广防己AristolochiafangchiY.C.WuexL.D.Chou.etS.M.Hwang的干燥根,习称"木防己"、"水防己",主产于广东、广西,具有祛风止痛、清热利水之功效。广防己主要成分为为生物碱及挥发油,己有报道的生物碱主要有:木防己碱、异木防己碱、木兰花碱、木防己胺、大防己宾碱、甲门尼萨任碱。挥发油成分未见报道,本文采用气相色谱-质谱(GC-MS)测定广防已挥发油成分,建立能够反映出定性、定量信息的GC-MS指纹谱图。结果表明:挥发油中主要含有β-古芸烯     

新型汉防己甲素衍生物的合成及其生物活性

以汉防己甲素为原料,经溴代反应制得关键中间体5-溴汉防己甲素(2); 2与硼酸衍生物经Suzuki反应合成了6个新型的汉防己甲素衍生物(4a~4f),其结构经¹H NMR, ¹³C NMR和ESI-MS表征。采用CCK-8法初步考察了4a~4f对人早幼粒白血病细胞(HL60)和人肺癌细胞(A549)的抑制活性;并采用MTT法对活性较好的化合物进行复筛。采用酶联免疫吸附法考察4a~4f对多种受体酪氨酸激酶的抑制活性。结果表明：4b, 4c和4e对HL60和A549有一定的抑制活性; 4b和4c对受体酪氨酸激酶FGFR1的抑制活性大于50%。     

粉防己碱及其衍生物的全合成与结构修饰

粉防己碱为双苄基异喹啉类化合物,主要分布在防已科千金藤属植物粉防己的块根中,具有多种生物活性如镇痛消炎、降压、抗肝纤维化和抗肿瘤等,其中,粉防己碱在抗肿瘤方面的药理活性尤为突出。由于此类化合物具有良好的药理活性,吸引了大量有机合成和药物化学等领域学者的关注。因此,本文从粉防己碱的全合成出发,重点综述了其C-5位,C-14及N-甲基位等位点的结构修饰的方法。在此基础上,对粉防己碱抗肿瘤方面的应用进展进行综述,并简要介绍其合成路线,为新药的研究与开发寻找一条条件温和、产率高、绿色安全、原料易得的合成路线。     

汉黄芩素的方便合成

汉黄芩素(Wogonin)是一种重要的黄酮类化合物,具有广泛的药理活性,其研究越来越受到重视.汉黄芩素的大量获得是对其深入研究的基础,但目前存在从天然产物中提取困难、全合成原料不易获得、反应条件苛刻、贵重及有毒试剂的使用、分离纯化困难或收率低等问题.以间苯三酚为原料,经七步反应得到汉黄芩素,总收率达到58%.具有原料及试剂便宜易得、反应条件温和、操作简便及无需柱层析纯化等优点,为汉黄芩素的规模化制备及深入研究奠定了基础.     

高效液相色谱法测定大鼠血浆中防己诺林碱和粉防己碱

建立了高效液相色谱(HPLC)快速测定血浆中2种生物活性碱-防己诺林碱和粉防己碱的方法.血浆经乙腈沉淀蛋白,稀释后直接进样,采用ODS C18柱,乙腈-磷酸缓冲液-三乙胺(80∶30∶0.3,V/V/V)为流动相,紫外检测波长282 nm,外标法定量.为研究防己诺林碱和粉防己碱在生物体内的药物代谢机理研究提供了简便、灵敏、准确的分离测定方法.     

1,4,5,8-四甲氧基萘-2-甲醛的合成工艺研究

紫草素（shikonin）为中药紫草中的有效成分，具有多种生物学活性，如抗菌、抗炎、抗病毒、抗肿瘤、抗生育、抗甲状腺亢进、抗免疫低下、降血糖、保肝扩肝等多种作用，引起人们对其合成的重视，有许多紫草素的全合成研究报道。多数以1，4，5，8-四甲氧基萘-2-甲醛（1）为起始原料，但收率均不高。     

粉防己碱-N-氧化物的化学研究

粉防己碱(tetrandrine以下简称TD,即汉防已甲素)是一种双苄基异喹啉生物碱,具有多种药理作用。1975年我国发现它可以治疗实验性矽肺,临床实践表明,它有使矽肺患者X-胸片好转、症状减轻的疗效。为了寻找高效低毒的抗矽肺药物,研究了TD在体内的代谢,我们用过氧化氢氧化TD获得了四种N-氧化物。有关生物碱-N-氧化物的化学以及它们在动植物体内的重要作用已有报道。Dahmen等从Cyclea barbata Miers中分离得到粉防己碱-2’-氧化物,而用过氧化氢氧化TD得到含有上述氧化物的混合物。 TD含两个氮原子,按照预想,N-氧化形成新的不对称氮中心,可能生成四种一氧化     

冬凌草甲素的结构修饰与生物活性研究进展

冬凌草甲素为对映贝壳杉烷类二萜化合物,主要分布在中草药冬凌草及相关植物中,具有多种生物活性如抗肿瘤、抗菌、抗炎等.主要综述了2000年以来冬凌草甲素的多功能结构修饰,表明冬凌草甲素结构修饰是提高冬凌草甲素药理活性的一种有效途径.     

Hetisine型C_(20)二萜生物碱绣线菊碱Ⅳ和Ⅺ的全合成

正以抗心律失常药关附甲素为典型代表的hetisine型C_(20)二萜生物碱具有丰富多样的生物活性和复杂的化学结构,数十年来一直是有机合成化学研究的热点,很多国际上著名的全合成小组相继进行了全合成研究.基于目前对C_(20)二萜生物碱的合成研究,hetisine型C_(20)二萜生物碱全合成的挑战在于C(14)—C(20)键和C(6)—N键的构建.重庆大学     

Separation of Alkaloids Extracted from Stephania Tetranda S. Moore by Analytical High-Speed Countercurrent Chromatography

Abstract

High-Speed countercurrent chromatography is a recently developed separation method which has been remarkably improved in both partition efficiency and separation time. In the present study, this advanced countercurrent chromatographic method was applied to separation of sample mixture containing tetrandrine, fangchinoline, and cyclanoline originally extracted from

Stephania tetrandra S. Moore. Separations were performed with a two-phase solvent system composed of n-hexane/ethyl acetate/methanol/water in two different elution modes. Sample mixture containing 3 mg of alkaloids was efficiently separated in 100 min. The peak fraction of each component was analyzed with a mass spectrometer for structure identification.     

Ultra high performance liquid chromatography with tandem mass spectrometry method for the determination of tetrandrine and fangchinoline in rat plasma after oral administration of Fangji Huangqi Tang and Stephania tetrandra S. Moore extracts

A rapid, sensitive, and reliable analytical method based on ultra high performance liquid chromatography with tandem mass spectrometry has been developed for the simultaneous determination of fangchinoline and tetrandrine in rat plasma. Plasma samples were pretreated by protein precipitation with acetonitrile. The analysis was performed on a C₁₈ reversed‐phase ultra high performance liquid chromatography column (2.1 mm × 100 mm, 3.5 μm, Agilent), and the flow rate was set at 0.4 mL/min. Under the experimental conditions, extraction recoveries from plasma were 68.1–72.8% for fangchinoline and 69.2–76.5% for tetrandrine. The plasma concentrations of tetrandrine and fangchinoline in rats at assigned time points were all successfully detected through exactly validated method. Good linearities were obtained in the range of 0.92–184 ng/mL for tetrandrine and in the range of 0.83–166 ng/mL for fangchinoline. The intra‐ and interday precisions for both analytes were within 11.1% and the accuracies were within the range of –10.7 to 11.3%. The developed method was then successfully applied to investigate the pharmacokinetic properties of these two alkaloids after oral administration of Stephania tetrandra S. Moore extracts and Fangji Huangqi Tang. The comparative results provided a meaningful basis for a better understanding of the practical value of the compatibility theory of traditional Chinese medicine in the clinic.     

Simultaneous determination of fangchinoline and tetrandrine in Stephania tetrandra S. Moore by using 1-alkyl-3-methylimidazolium-based ionic liquids as the RP-HPLC mobile phase additives

A reversed phase high performance liquid chromatography (RP-HPLC) method for simultaneous determination of fangchinoline (FAN) and tetrandrine (TET) in Stephania tetrandra S. Moore was established by using 1-hexyl-3-methylimidazolium tetrafluoroborate as the mobile phase additives in this paper. Four types of 1-alkyl-3-methylimidazolium-based ionic liquids (ILs) were used as additives of the mobile phase to separate FAN and TET by RP-HPLC. The effects of the length of the alkyl group on the imidazolium ring and its counterion, the concentrations of IL and the pH of the mobile phase, which influenced the chromatographic behaviors of FAN and TET, were investigated in detail. The linearity, sensitivity, accuracy and repeatability of the proposed method were also investigated. The probable mechanism of the separation with ILs as the mobile phase additives was explored and discussed.     

微量热法测定粉防己碱金属配合物的抑菌性

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。     

Screening and investigation of triplex DNA binders from Stephania tetrandra S. Moore by a combination of peak area‐fading ultra high‐performance liquid chromatography with orbitrap mass spectrometry and optical spectroscopies

The identification and screening of triplex DNA binders are important because these compounds, in many cases, are potential anticancer agents as well as promising drug candidates. Therefore, the ability to screen for these compounds in a high‐throughput mode could dramatically improve the drug screening process. A method involving a combination of 96‐well plate format and peak area‐fading ultra high‐performance liquid chromatography coupled with Orbitrap mass spectrometry was employed for screening bioactive compounds binding to the triplex DNA from the extracts of Stephania tetrandra S. Moore. Two compounds were screened out and identified as fangchinoline and tetrandrine based on the comparison of retention time and tandem mass spectrometry data with those of standards. The binding mechanisms of fangchinoline and tetrandrine at the molecular level were explored using tandem mass spectrometry, fluorescence spectroscopy, ultraviolet‐visible spectroscopy, and circular dichroism. Collision‐induced dissociation experiments showed that the complexes with fangchinoline and tetrandrine were dissociated by ligand elimination. According to these measurements, an intercalating binding is the most appropriate binding mode of these two alkaloids to the triplex DNA. The current work provides not only deep insight into alkaloid‐triplex DNA complexes but also useful guidelines for the design of efficient anticancer agents.     

反相高效液相色谱法测定三种中药中粉防己碱

本文首次用反相高效相色谱法分离并测定了粉防己，头花千金藤，蝙蝠葛三种中药中的粉防己碱，建立了中粉防己碱分离，测定了色谱方法，色谱条件：ＯＤＳ柱，甲醇－水－三乙胺（８５：１５：０．２５Ｖ／Ｖ）为流动相，紫外检测器测波长２８３ｎｍ。本研究的扩大中药及植物中粉防己碱药物资源的开发提供了简便，灵敏，准确的分离，测定方法。     

Pharmacokinetics of 10‐hydroxycamptothecin–tetrandrine liposome complexes in rat by a simple and sensitive ultra‐high performance liquid chromatography with tandem mass spectrometry

10‐Hydroxycamptothecin is a drug to cure various cancers. However, the 10‐hydroxycamptothecin cannot be widely applied in clinics due to fast elimination and resistance of various cancers to the drug. Nevertheless, co‐treatment with tetrandine is known to reverse the resistance of multi‐drug resistant cancers, and may present an effective strategy to improve the efficacy of 10‐hydroxycamptothecin. In order to improve the bioavailability and prolong the treatment time of the 10‐hydroxycamptothecin in vivo, we prepared 10‐hydroxycamptothecin‐tetrandrine liposome complexes with 10‐hydroxycamptothecin as the basic anticancer drug, tetrandrine and liposomes as carriers. In this article, an ultra‐high performance liquid chromatography tandem mass spectrometry method for the analysis of 10‐hydroxycamptothecin and tetrandrine in plasma has been developed, validated, and utilized to compare the pharmacokinetics of both drugs in the original dosage form and administered as liposome complexes. According to the pharmacokinetic parameters of mean residence time, half‐life period and clearance rate, the 10‐hydroxycamptothecin‐tetrandrine liposome complexes prolongs the retention and circulation time of 10‐hydroxycamptothecin in vivo, achieving a good sustained release effect. To the best of our current knowledge, the pharmacokinetic properties of 10‐hydroxycamptothecin‐tetrandrine liposome complexes in rats have not been reported yet. Our study can provide a helpful reference for further related study.     

Evaluation of the interaction of bioactive compounds in Cortex Pseudolarix and Radix Stephaniae by the microdialysis probe coupled with high performance liquid chromatography-mass spectrometry

An efficient and convenient method, biological fingerprinting chromatogram analysis is presented, which is applied to the comparison of fingerprinting chromatograms of the extracts of Chinese herbal medicines after the interaction with biological systems (cell, DNA, protein, etc.). The method was established for the purpose of screening and analysis of the multiple bioactive compounds in herbal medicines. In this work, microdialysis sampling combined with high performance liquid chromatography-mass spectrometry (HPLC-MS) was studied for binding property of MCF-7 and multidrug resistant MCF-7 cell systems. The results showed that pseudolaric acid A (PAA) and pseudolaric acid B (PAB) in the cortex of Pseudolarix kaempferi (Lamb.) Gorden can easily bind to the MCF-7 cells ranging from 0 to 16.3% (PAA) and from 0 to 35.7% (PAB), and another compound, tetrandrine (TET) from the root of Stephania tetrandrae S. Moore, showed higher binding activity with multidrug resistant MCF-7 cells ranging from 0 to 39.9%.     

Interaction of tetrandrine with human serum albumin: a fluorescence quenching study.

The interaction of tetrandrine with human serum albumin (HSA) was studied by measuring fluorescence quenching spectra, synchronous fluorescence spectra and ultra-violet spectra. The fluorescence quenching spectra of HSA in the presence of tetrandrine showed that tetrandrine quenched the fluorescence of HSA. The quenching constants of tetrandrine on HSA were determined using the Stern-Volmer equation. Static quenching and non-radiation energy transfer were the two main reasons leading to the fluorescence quenching of HSA by tetrandrine. According to the F?rster theory of non-radiation energy transfer, the binding distances (r) and the binding constants (K(A)) were obtained. The thermodynamic parameters obtained in this study revealed that the interaction between tetrandrine and HSA was mainly driven by a hydrophobic force. The conformational changes of HSA were investigated by synchronous spectrum studies.