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1.
滇重楼地上部分的两个微量皂甙   总被引:10,自引:1,他引:9  
从滇重楼地上部分中分离出两个新的微量的甾体皂甙PolyphyllosideⅢ和Ⅳ,根据化学降解和光谱分析,它们的化学结构分别为27-羟基-偏诺皂皂甙元-3-O[a-L-鼠李吡喃糖基(1→2)][a-L-鼠李吡喃糖基(1→4-a-L鼠李吡喃糖基(1→4)]-β-D-葡萄吡喃糖甙,23β,27-二羟基-偏皂甙元-3-O-[a-鼠李吡喃糖(1→2)]  相似文献   

2.
鞭打绣球中的苯丙素甙和环烯醚萜甙   总被引:6,自引:0,他引:6  
从鞭打绣球(HemiphragmaheterophyllumWall.)(玄参科)的全草中分离到2个新的苯丙素甙,命名为鞭打绣球甙A和B(hemiphrosideAandB),2个已知的苯丙素甙,plantamajoside和plantainosideD,以及3个已知的环烯醚萜甙,globularicisin,globularin和iso-scrophularioside.通过化学和光谱分析,鞭打绣球甙A和B的结构分别鉴定为2-(3-羟基-4-甲氧基苯基)乙基0-β-D-葡萄吡喃糖基(1→3)-4-O-反式阿魏醚基-β-D-葡萄吡喃糖试和2-(3,4-二羟基苯基)乙基O-[6-O-乙醚基-β-D-葡萄吡喃糖基(1→3)]-4-O-反式咖啡醚基-β-D-葡萄吡喃糖甙.  相似文献   

3.
滇重楼地上部分的配糖体   总被引:13,自引:0,他引:13  
从滇重楼ParispolyphyllaSm.var.yunnanensis(Fr.)H-M,地上部分,分离出4个微量的配糖体,经光谱分析和化学降解证明其化学结构分别为25S-异钮替皂甙元-3-O-α-L-鼠李吡喃糖基(1→2)[α-L-鼠李吡喃糖基(1→4)]-β-D-葡萄吡喃甙(A),26-β-D-葡萄吡喃糖基-纽替皂甙元-3-O-α-L-鼠李吡喃糖基(1→2)[α-L-鼠李吡喃糖基(1→4)-β-D-葡萄吡喃糖甙(B),山奈酚-3-O-β-D-葡萄吡喃糖基(1→6)-β-D-葡萄吡喃甙(C),7-O-α-L-鼠李吡喃糖基-山奈酚-3-O-β-D-葡萄吡喃糖基(1→6)-β-D-葡萄糖甙(D)。  相似文献   

4.
仙茅根茎中的配糖体   总被引:5,自引:0,他引:5  
从仙茅( Curculigo orchioidesGaertn) 根茎中分离到7 个化合物, 经光谱分析推定其化学结构分别为: 2, 6 - 二甲氧基苯甲酸(A) ; 苔黑酚葡萄糖甙(B) ; 仙茅素A (C) ; 仙茅甙(D) ; 24s, 3β, 11α, 16β, 24 - 四羟基环阿尔廷醇- 3 - O- α- L- 鼠李吡喃糖基(1 →2) - β-D- 葡萄吡喃糖甙(E) ; 24s, 3β, 11α, 16β, 24 - 四羟基环阿尔廷醇- 3- O- β- D- 葡萄吡喃糖基(1 →2) - β- D- 葡萄吡喃糖甙(F) 和胡萝卜甙(G) 。F为一新甙。  相似文献   

5.
石香薷中化学成分的研究   总被引:13,自引:0,他引:13  
从石香薷(Mosla chinensis Maxim .)中分离到10 个化合物,经光谱分析、化学方法及与已知化合物对照,分别鉴定为:6-甲基三十三烷(1)、β-谷甾醇(2)、熊果酸(3)、5-羟基-6,7-二甲氧基黄酮(4)、5-羟基-6-甲基-7-O-β-D-吡喃木糖(3→1)-β-D-吡喃木糖双氢黄酮甙(5)、5,7-二羟基-4-甲氧基黄酮(6)、洋芹素(7)、山奈素-3-O-β-D-葡萄糖甙(8)、桑色素-7-O-β-D-葡萄糖甙(9)、鼠李柠檬素-3-O-β-D-芹糖(1→5)芹糖-4-O-β-D-葡萄糖甙(10)。其中,化合物5和10 为新化合物  相似文献   

6.
从栓皮栎(Quercus variabilisBl.)虫瘿中分离了2对平衡互变异构体和4个单体化合物,通过光谱数据和化学方法鉴定:G-1为1-O(3′-没食子酰基)没食子酰基-β-D-葡萄吡喃糖和1-O-(4′-没食子酰基)没食子酰基-β-D-葡萄吡喃糖的平衡互变异构体,G-2为3-O-没食子酰基-没食子酸和4-O-没食子酰基--没食子酸的平衡互变异构体,-3O一1,6-二-O没食子酰基-β-D-葡萄吡喃糖,G-4为1,2,3,6-四-O-没食子酰基-β-D-葡萄吡喃糖,G-5为1-O-没食子酰基-β-D-葡萄吡喃糖,G-6为没食子酸甲酯。对G-1、G-3和G-4进行初步的抗肿瘤、抗脂质过氧化和抗血小板聚集活性实验。  相似文献   

7.
闭鞘姜根中的甾体皂甙   总被引:4,自引:0,他引:4  
从闭鞘姜「Costus speciosus(Koenig)Smith」根茎中分离出五个化合物。经波谱解析和化学降解,证明其化学结构分别为胡萝卜甙(A):薯芋皂甙元3-O-a-L鼠李吡喃糖基(1-2)-β-D-葡萄吡喃糖甙(B);薯芋皂甙元3-O-a-L-鼠李吡喃糖基(1-2)「a-L-鼠李吡喃糖基(1-4)」β-D葡萄吡喃糖甙(C);薯芋皂甙元-3-O-a-L-鼠李吡喃糖基(1-2)「β-D-葡萄  相似文献   

8.
滇黄芩甙A和B的结构   总被引:3,自引:1,他引:2  
从龙胆科滇黄芩属植物滇黄芩(Veratrilla baillonii Franch)中分离得到两个新的酮二糖甙,经~1H NMR,~(13)C NMR,FAB-MS,MS,2D NMR,UV,IR等物理方法和化学反应,推定为:2,3,4,7-四甲氧基酮-1-O-β-D-葡萄糖(6←1)-β-D-木糖甙(1)和7-羟基-2,3,4-三甲氧基酮-1-O-β-D-葡萄糖(6←1)-β-D-木糖甙(2),分别命名为:滇黄芩甙A和滇黄芩甙B。  相似文献   

9.
蜘蛛抱蛋根茎中的甾体皂甙   总被引:6,自引:1,他引:5  
从蜘蛛抱蛋(AspidistraelatiorBl.)根茎的甲醇提取物中分离得两个甾体皂甙。经波谱解析及化学降解证明其化学结构分别为薯芋皂甙元一3一O-[B-D-葡萄吡喃糖基(1→2)]-[B-D-木吡喃糖基(1→3)]-B-D-葡萄吡喃糖基(1→4)-B-D一半乳吡喃糖甙(即蜘蛛抱蛋甙aspidistrin)及新静诺特皂甙元-3-O-[B-D-葡萄吡喃糖基(1→2)]~[B-D-木吡喃糖基(1→3)-B-D-葡萄吡喃糖基(1→4)一B-D-半乳吡喃糖甙,后者为一新试,命名为新蜘蛛抱蛋甙reoaspidistrin。  相似文献   

10.
滇黄芩中的两个山酮甙   总被引:2,自引:0,他引:2  
从龙胆科滇黄芩属植物滇黄芩中分离得到两个新的山酮甙,分别命名为:滇黄芩甙C(Ⅰ)和滇黄芩甙D(Ⅱ)。  相似文献   

11.
正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

12.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

13.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

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Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.  相似文献   

17.
Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8+ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8+ T cells are involved in the pathogenesis of RE.  相似文献   

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Shen  Jia-Yuan  Li  Man  Xie  Lyu  Mao  Jia-Rong  Zhou  Hong-Ning  Wang  Pei-Gang  Jiang  Jin-Yong  An  Jing 《中国病毒学》2021,36(1):145-148
正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).  相似文献   

20.
In conclusion, the novel visual RT-LAMP assay is a simple, rapid, and sensitive approach for detection of SARS-CoV-2, and it is ready for application in primary care and community hospitals or health care centers, and even patients' own houses in response to the current SARS-CoV-2 epidemic because the assay does not require sophisticated equipment and skilled personnel. Furthermore, it is also ready to be used in fields for screening samples from wild animals and environments to facilitate the identification of potential intermediate hosts that mediate the cross-species transmission of SARS-CoV-2 from bats to humans.  相似文献   

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