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1.
自番荔枝( AnnonasquamosaL.) 种子中得到化合物1 和2 , 化合物2 是已知的bullatacinone (2 , 4- 顺式和反式- bullatacinone 的混晶) , 1 是新化合物, 命名为番荔枝塔亭丁(squamostatin D) , 其结构经IR、MS、1H- NMR和13CNMR谱解析推定如(1) 式。  相似文献   

2.
南海柳珊瑚Isis sp.化学成分的研究   总被引:18,自引:1,他引:17  
从中国南沙采集的柳珊瑚Isis sp。中分离出四个有机化合物,通过UV,IR,MS,^1H-NMR和^13C-NMR分析以及化学转换的方法,确定了它们的结构分别为:Hippuristanol(1),Δ^4.5(E)、Δ^9.10(Z)-鞘氨醇-正十五碳酸酰胺(2),胸腺嘧啶(3)和尿嘧啶(4)。其中化合物(2)为新结构的神经酰胺,被命名为Isimamide,其它为已知化合物。  相似文献   

3.
长果升麻的化学成分研究   总被引:4,自引:0,他引:4  
从长果升麻(Souliea vaginata)根茎中分离出6种皂甙,经光谱(FAB-MS、1H-NMR、1H-1H-COSY、13C-NMR、1H-13C-COSY)分析,分别鉴定为27-deoxyactein(1),actein(2),25-0-乙酰升麻醇木糖甙(3),25-甲基升麻醇木糖甙(4),升麻醇木糖甙(5),24-acetylhydroshengmanol xyloside(6),其中  相似文献   

4.
灯盏细辛中酚类化合物的化学研究   总被引:10,自引:0,他引:10  
从灯盏细辛(Erigeron breviscapus(Van.)Hand-Mazz)的乙酸乙酯部分首次分离得到5个二咖啡酰基的酚类化合物(1 ̄5)和9个其他类型化合物。其中erigoster A(1)为一全新骨架的化合物。利用波谱方法(^1H-NMR,^13C-NMR,2D-NMR和FAB-MS等)对这些化合物的结构进行了鉴定。  相似文献   

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大花哥纳香化学成分研究   总被引:2,自引:0,他引:2  
从大花哥纳香(GoniothalamusgrifithiHokf.etThoms)的茎枝分得12个化合物,经光谱(IR,MS,NMR,2DNMR)分析,鉴定其中7个为苯乙烯内酯:goniothalamin(1)、9deoxygoniopypyrone(2)、altholactone(3)、goniodiol(4)、goniotharvensin(5)、goniofufurone(6)和8acetylgoniotriol(7)。另5个化合物鉴定为番荔枝内酰胺(squamolone,8)、乔松素(pinocembrin,9)、琥珀酸(succinicacid,10)、β谷甾醇(βsitosterol,11)和豆甾醇(stigmasterol,12)。化合物1~3和5~10均为首次从该植物分得。  相似文献   

6.
斜脉暗罗素甲—具有C5—OH的单四氢呋喃环型番荔枝内酯   总被引:2,自引:0,他引:2  
从斜脉暗罗(Polyalthia plagioneura Diels)的种子中分离到化合物P4 及P5,经IR、1H-NMR、13 C-NMR及MS谱鉴定,P4 为海南哥纳香甲素,P5 为具有C5-OH 的单四氢呋喃环型番荔枝内酯,命名为斜脉暗罗素甲(plagionicin A)。  相似文献   

7.
自头序Song木70%EtOH提取物分得6个化合物,应用光谱技术(IR,MS,HNMR,^13CNMR,DEPT,2DNMR)及化学方法,确定了他们的结构,分别为β-谷甾醇(Ⅰ),胡萝卜甙(Ⅱ),齐墩果酸(Ⅲ),竹节参皂甙1(Ⅳ),竹节参皂甙Ⅳa(ChikusetsusapominⅣa)(Ⅴ),常春藤皂甙元-28-O-β-吡喃葡萄糖醛酸(1→4)-β-D-吡喃葡萄糖甙(Ⅵ),以上化合物均为首次从该  相似文献   

8.
从羊红膻(PimpinelathelungianaWolf)根的75%乙醇提取物的乙醚萃取部分,分得一化合物。经光谱(UV、IR、1HNMR、13CNMR、1H1HCOSY、1H13CCOSY和MS)分析,确定为新化合物2(1甲氧基2羟基)丙基4甲氧基苯酚,命名为羊红膻素E(thelungianinE)。  相似文献   

9.
四种无尾两栖动物的核型和银染   总被引:4,自引:1,他引:4  
本文报道了二种角蟾和二种树蛙的核型和银染NOR:无量出角蟾:2n=26(24+2SM),5+8,SC和Ag-NORs位于6q^per沙坪角蟾:2n=26(16M+8SM+2ST),5+8,SC位于1q^per,但Ag-NORs有二对,分别是lq^per和2q^per;黑蹼树蛙:2n=26(24M+2SM),5+8,SC和Ag-NORs在lp^inter;背条跳树蛙;2n=16(12M+4SM),S  相似文献   

10.
朝鲜淫羊藿的化学成分(Ⅱ)   总被引:3,自引:1,他引:2  
从朝鲜淫羊藿的地上部分分离到七个成分(Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ)。经UV,IR,^1H-NMR,^13C-NMR,MS及化学方法鉴定了它们的结构,分别是icaritin-3-O-a-L-rhamnopyranoside(Ⅰ),sagittatoside A(Ⅱ),sagittatoside B(Ⅲ),3,5,7-trihydroxyl-4^1-methoxy1-8-preny1-flavone-  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   

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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   

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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   

20.
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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