异甜菊醇药理活性研究进展

异甜菊醇具有广泛的药理活性,在降低血压、抗肿瘤、抗心肌缺血复灌损伤等方面具有重要功效,实验表明其还对受体种子具有萌发作用并且能作为一种新的胰岛素增敏剂用于治疗Ⅱ型糖尿病。因为异甜菊醇本身特有的二萜骨架,它可作为药物合成中常用的活性框架。本文对异甜菊醇结构修饰和改造及药代学活性研究进行了综述。     

异甜菊醇衍生物结构修饰及活性研究

异甜菊醇具有抗高血压、降低血糖、抑制癌细胞等药理作用,对近年来关于异甜菊醇研究的反应类型及生物活性进行了初步的综述。     

甜菊醇和异甜菊醇与DNA作用方式的研究

甜菊醇是新型甜味剂甜菊糖在人体内的代谢产物,在酸性环境中可重排成异甜菊醇,它们都是重要的药物合成中间体.研究甜菊醇和异甜菊醇与DNA的作用方式有助于理解其药理或细胞毒性.以小牛胸腺DNA(CT-DNA)为模板,通过考察甜菊醇和异甜菊醇对CT-DNA熔点和粘度的影响,以及甜菊醇和异甜菊醇与CT-DNA体系紫外吸收的变迁,初步推断甜菊醇和异甜菊醇都是以沟槽方式与CT-DNA结合;异甜菊醇与CT-DNA的作用比甜菊醇与CT-DNA作用强.     

盐酸或氨基磺酸催化水解斯替夫苷制备甜菊醇

分别以盐酸或氨基磺酸为催化剂水解斯替夫苷(St),研究底物质量浓度、反应温度、催化剂用量和反应时间对斯替夫苷水解的影响,着重考察了斯替夫苷的转化率、甜菊醇的产率和异甜菊醇的产率。其中,盐酸催化水解斯替夫苷的最优工艺条件为:反应温度95℃,底物质量浓度400 g/L,盐酸浓度0.04 mol/L,反应时间28 h;在该条件下,根据高效液相色谱分析计算得到斯替夫苷转化率接近100%,甜菊醇产率达83.6%,异甜菊醇产率达12.4%。氨基磺酸催化反应的工艺条件为:反应温度95℃,斯替夫苷质量浓度400 g/L,氨基磺酸浓度0.05 mol/L,反应时间31 h;在该条件下,根据高效液相色谱分析计算得到斯替夫苷转化率接近100%,甜菊醇产率达81.5%,异甜菊醇产率达11.7%。     

苄基异喹啉类生物碱的药理活性研究进展

苄基异喹啉类生物碱(Benzylisoquinoline alkaloids,BA)药理活性广泛,药理学研究已经证实苄基异喹啉类生物碱具有抗肿瘤、抗炎、抗氧化、心血管保护、抗菌、肌肉松弛以及中枢神经系统等方面的药理作用。另外,抗埃博拉病毒等新活性的发现也为苄基异喹啉类生物碱的进一步研究注入新的活力。本文通过总结近十年国内外的相关文献,对BA的药理活性进行了综述。     

小檗碱及其衍生物的抗癌机制研究进展

小檗碱又称黄连素,是一种异喹啉类季铵生物碱,具有抗菌抗炎、止泻、抗高血压、降血脂等作用。近年来研究发现小檗碱还有抗肿瘤的作用,而且毒副作用小,使得小檗碱在抗肿瘤研究方面前景更加广阔。但是小檗碱在肠道吸收较差,药理作用也还需要经临床研究进一步证实。近年来也有很多研究者对小檗碱的不同位点进行了结构修饰,期望得到水溶性更好,抗肿瘤活性更高的衍生物。本文就小檗碱及其衍生物的抗肿瘤机制的研究进展进行综述。     

广西莪术化学成分和药理作用研究进展

查阅近年有关文献,对广西莪术的化学成分和药理作用进行综述。广西莪术主要含有挥发油、二苯基庚烷等成分,具有抗肿瘤、保肝、凝血、镇痛抗炎、抗病毒、抗菌等作用。广西莪术中莪术醇是临床药物莪术油的药效成分,二苯基庚烷类成分姜黄素具有显著的抗肿瘤活性。广西莪术为广西的道地药材,资源相当丰富,应在民间用药的基础上进行系统的化学成分和生物活性研究,为进一步开发利用奠定基础。     

雪松醇的合成应用及其药理作用研究进展

雪松醇(Cedrol,CE),是一种用途极为广泛的天然倍半萜醇,广泛存在于柏科、杉科及松科等多种植物的挥发油中.研究报道CE存在多种药理作用,包括抗炎镇痛、对心脑血管系统作用、抗肿瘤、促进头发生长、抗菌、抗疟原虫活性等.为拓宽其应用,加速其新药研发进程,有必要对其研究进行总结.通过查阅相关文献,归纳总结了CE的提取与检...     

传统中药金银花的药理作用研究进展

金银花是一种广泛使用的传统中药,在中国使用已经有上千年的历史。其主要化学成分为绿原酸、异绿原酸、芳香醇、木犀草素、金银花皂苷以及黄酮类化合物。目前国内外的研究证实金银花具有具有广谱抗菌、抗病毒、抗炎解热、抗氧化、免疫调节和抗肿瘤等作用。主要针对金银花的药理作用进行综述,为金银花的进一步研究提供参考。     

香豆素类化合物生理药理活性的研究

简要综述了香豆素化合物的抗病毒、抗真菌、抗肿瘤、抗炎及抗骨质疏松等生理药理活性。     

Synthesis and Biological Application of Isosteviol-Based 1,3-Aminoalcohols

Starting from isosteviol, a series of diterpenoid 1,3-aminoalcohol derivatives were stereoselectively synthesised. The acid-catalysed hydrolysis and rearrangement of natural stevioside gave isosteviol, which was transformed to the key intermediate methyl ester. In the next step, Mannich condensation of diterpenoid ketone, paraformaldehyde, and secondary amines resulted in the formation of 1,3-aminoketones with different stereoselectivities. During the Mannich condensation with dibenzylamine, an interesting N-benzyl → N-methyl substituent exchange was observed. Reduction of 1,3-aminoketones produced diastereoisomeric 1,3-aminoalcohols. Alternatively, aminoalcohols were obtained via stereoselective hydroxy-formylation, followed by oxime preparation, reduction, and finally, reductive alkylation of the obtained primary aminoalcohols. An alternative 1,3-aminoalcohol library was prepared by reductive amination of the intermediate 3-hydroxyaldehyde obtained from isosteviol in two-step synthesis. Cytotoxic activity of compounds against human tumour cell lines (A2780, SiHa, HeLa, MCF-7 and MDA-MB-231) was investigated. In our preliminary study, the 1,3-aminoalcohol function and N-benzyl substitution seemed to be essential for the reliable antiproliferative activity. To extend their application, a diterpenoid condensed with 2-phenylimino-1,3-thiazine and -1,3-oxazine was also attempted to prepare, but only formation of thioether intermediate was observed.     

异斯特维醇衍生物的应用研究进展

异斯特维醇是由天然产物甜菊糖苷经酸解得到,其衍生物在生物活性方面的应用研究较多。本文对异斯特维醇衍生物在生物活性、催化剂、分子识别和超分子组装等领域的应用进行了综述。     

二氯荧光素二丙烯酸酯的合成与抗肿瘤活性研究

合成了化合物二氯荧光素二丙烯酸酯(Ⅰ),用元素分析、IR、1HNMR、UV、荧光光谱对它进行了表征。测试了Ⅰ对小鼠白血病L1210细胞生长曲线的影响和对人体胃腺癌SGC-7901的抗肿瘤活性。结果表明,Ⅰ对体外培养肿瘤细胞L1210有很强的瞬时杀伤作用〔在ρ(Ⅰ)=0 1μg mL时,24h对其杀死率几乎为100%〕;对人体胃腺癌SGC-7901有很强的细胞增殖的抑制作用〔在ρ(Ⅰ)=0 1μg mL时,克隆数约为(3±1.1)%,集落形成率=0 15%,存活率=0 4%〕。是有希望的脂溶性、带荧光的抗肿瘤药学化合物。     

熊果酸的抗肿瘤活性及作用机理研究进展

熊果酸属五环三萜类化合物,来源丰富,具有广泛的生物活性。概述了熊果酸在医药领域的研究进展,着重论述了熊果酸的抗肿瘤活性及其抗肿瘤作用机理,并对熊果酸的研究开发前景进行了探讨。     

Highly Enantioselective α-aminoxylation Reactions Catalyzed by Isosteviol-proline Conjugates in Buffered Aqueous Media

Abstract  

Chiral amphiphilic conjugate catalysts were designed and synthesized by covalently connecting l-proline with an inexpensive natural product, isosteviol. These catalysts demonstrated remarkable efficiency in the asymmetric α-aminoxylation of aldehydes and ketones using nitrosobenzene in phosphate buffer solution, resulting in good to high yields and excellent enantioselectivities without using any additives. At pH 9.1, the amphiphilic catalysts showed a pH responsive ability in phosphate buffer solution, which facilitated the excellent O-selectivity reactions, illustrating a viable approach for the development of asymmetric supra-molecular catalysts.     

低分子糖抗肿瘤活性的研究进展

低分子糖亦称寡聚糖,由2～10个单糖单元通过苷键结合而成,较之多糖具有独特的结构。低分子糖的生物活性,特别是抗肿瘤活性与其结构密切相关,已成为当今糖化学领域的研究热点。综述了寡聚糖的化学结构及其抗肿瘤的构效关系等相关研究新进展。并指出低分子糖作为抗肿瘤药物的研究方向。     

白藜芦醇及其衍生物和类似物抗肿瘤研究进展

白藜芦醇具有广泛的生物学活性,尤其是抗肿瘤作用备受关注,得到了广泛研究。同时,为了提高生物利用度,并获得更高的抗肿瘤活性,有关其衍生物与类似物的研究也大量开展。本文对白藜芦醇的结构及理化性质、抗肿瘤作用机制、毒性、代谢动力学、白藜芦醇衍生物和类似物的抗肿瘤活性及作用机制,以及制备方法进行了回顾。作为一类很有希望的的新型抗肿瘤药物,有关白藜芦醇及其衍生物和类似物还存在许多需要继续研究的问题,包括生物作用机制、结构与活性的关系不明确、生物利用度与疗效之间存在的矛盾以及体内药代动力学研究的缺乏等,还需要系统开展作用机制、毒理学和代谢动力学研究以及动物体内试验。     

Aristoforin, a novel stable derivative of hyperforin, is a potent anticancer agent

Hyperforin, a natural product of St. John's wort (Hypericum perforatum L.), has a number of pharmacological activities, including antidepressive and antibacterial properties. Furthermore, hyperforin has pronounced antitumor properties against different tumor cell lines, both in vitro and in vivo. Despite being a promising novel anticancer agent, the poor solubility and stability of hyperforin in aqueous solution limits its potential clinical application. In this study, we present the synthesis of hyperforin derivatives with improved pharmacological activity. The synthesized compounds were tested for their solubility and stability properties. They were also investigated for their antitumor properties, both in vitro and in vivo. One of these hyperforin derivatives, Aristoforin, is more soluble in aqueous solution than hyperforin and is additionally highly stable. Importantly, it retains the antitumor properties of the parental compound without inducing toxicity in experimental animals. These data strongly suggest that Aristoforin has potential as an anticancer drug.