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1.
毛喉鞘蕊花的微量成分   总被引:10,自引:0,他引:10  
从唇形科毛喉鞘蕊花全草的氯仿提取物分离到2个新的微量成分,鞘蕊花戊素和已素。基于光谱分析,鞘蕊花戊素和已 素的化学结构分别鉴定为1α,7β-二乙酰氧基-8,13-环氧-6β羟基勒丹-14烯-11-酮(1)和7β-乙酰氧基-8,13环氧-6β,α-二羟基勒丹-14烯-11-酮(2)。  相似文献   

2.
茜草乔木酮乙和丙的结构   总被引:5,自引:0,他引:5  
从小红参(Rubiayunnanensis)中分离鉴定了2个新的乔木烷型三萜,分别命名为茜草乔木酮乙和丙(rubiarbononeB,C)。用光谱和化学方法证明它们的结构分别为:7β,19α,28-三羟基乔木-9(11)-烯-3-酮和28-乙酰氧基-7β,19α-二羟基乔木-9(11)-烯-3-酮。  相似文献   

3.
冬凌草中一新的二萜成分--冬凌草辛素   总被引:4,自引:0,他引:4  
从河南省鹤壁地区产冬凌〖Isodon rubescens(Hemsl.)Hara〗叶中分得一个新地二萜化合物,命名为冬凌草辛素(Rubescensin H)〈经NMR谱等确定其结构为6β,7β,14β,15R-四羟基-11β-甲酰氧基-7α,20-环氧-对映-贝壳杉-16-烯。  相似文献   

4.
细锥香茶菜化学成分的研究   总被引:3,自引:0,他引:3  
从细锥香茶菜(Rabdosiacoetsa(Buch.Ham.exD.Don)Hara)的叶中分离到9个化合物,通过波谱分析阐明其结构,其中1个为新的二萜酸———7α,12α,14β三羟基15酮对映贝壳杉18羧酸,命名为细锥香茶菜酸(coetsanoicacid)。另外8个化合物分别为二氢昆明香茶菜丙素、昆明香茶菜丙素、白柔毛香茶菜甲素、大萼香茶菜丙素、4羟基Δ8,9(Z)鞘氨醇2′羟基正二十(二十一二十六)碳酸酰胺、乌苏酸、2α,3β二羟基乌苏酸和胡萝卜甙。神经酰胺类化合物系首次从该属植物中分离得到。  相似文献   

5.
疏花毛萼香茶菜中一新的对映-贝壳杉烷型二萜   总被引:1,自引:0,他引:1  
从疏花毛萼香茶菜(Isodon eriocalyx var.laxiflora)叶中分离得到一新的对映-贝壳杉烷型二萜,命名为疏花丁素(1),通过波谱方法鉴定了它的结构。此外,还分离得到6个已知对映-贝壳杉烷型二萜化合物:疏花甲素(2),毛萼晶A-C(3-5)和Q(6),毛萼乙素(7),以及cirsimaritin(8)和2α-羟基乌索酸(9)。  相似文献   

6.
细锥香茶菜二萜的研究   总被引:1,自引:0,他引:1  
从四川省峨眉山产细锥香茶菜[Rabdosia coetsa(Buch-Ham,ex,D.Don)Hara]乙醚抽提物中分得了一个新二萜化合物,命名为细锥香茶菜丁素(rabdocoetsin D),其结构经各项波谱数据和化学证据确定为1α,7β-二羟基-11β-乙酰氧基-对映-7β,20-环氧-贝壳杉-16-烯-15-酮(1)。另外还分离到3个已知二萜,细锥香茶菜乙素(rabdocoetsin B)、细锥香茶菜丙素(rabdocoetsin C)、瘿花香茶菜甲素(rosthorin A)。  相似文献   

7.
藤山柳的化学成分   总被引:4,自引:0,他引:4  
从藤山柳〖Clematoclethra scandens(Franch.)Maxim〗根茎甲醇提取物的石油醚和波谱分析,分离出8个化合物,经理化常数和波谱分析,分别鉴定为:7-羧基贝壳杉烯内酯(1),蒲公英赛烷醇(2),桦木酸(3),乌苏酸(4),2α,3α,23-三羟基乌苏-12-烯-28-酸(50,2α3α23-三羟基乌苏-12,20(30)-二烯-280酸(6),豆甾-4-烯-3,6-二酮(  相似文献   

8.
从云南省会泽县产近无毛灰岩香茶莱〔Rabdosia calcicola (Hand. -Mazz.) Hara var. subculva (Hand. -Mazz.) C. Y. Wu et H. W. Li〕叶中分得两个二萜化合物,一个为新化合物,命名为灰岩香茶菜甲素(calcieolin A),另一个为已知化合物维西香茶菜甲素(weisiensin A),经各项光谱数据和化学反应确定,灰岩香茶菜甲素为3β-羟基-1α,6α,7β,11β-四乙酰氧基-对映-贝壳杉-16-烯-15-酮(1);维西香茶菜甲素结构应为3β,6α-二羟基-1α,7β,11β-三乙酰氧基-对映—贝壳杉-16-烯-15酮(2)。  相似文献   

9.
鲁山冬凌草戊素的结构   总被引:2,自引:0,他引:2  
从鲁山冬凌草叶中分得一个新的二萜化合物,鲁山冬凌草戊素(lushanrubesensin E),其结构经各项光谱数据确定为对映-2α,11β-二羟基-3α,6β-二乙酰氧基-16-贝壳杉烯-15-酮。  相似文献   

10.
毛萼鞘蕊花甲素的结构   总被引:2,自引:1,他引:1  
从毛萼鞘蕊花(Coleus esquirolii(L(?)vl. )Dunn.)的茎、叶中分离鉴定了一个新的二萜化合物,毛萼鞘蕊花甲素(对映-17-乙酰氧基-贝壳杉烷-16β-醇),和三个已知化合物,对映-贝壳杉烷-16p,17-二醇,齐墩果酸和β-谷甾醇。  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.
14.
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   

15.
16.
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   

18.
19.
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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