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1.
以4-甲氧基苯基-β-D-吡喃葡萄糖苷为原料,经9步反应制得新型关键中间体2,4,6-三-O-苄基-3-羰基-D-葡萄糖酸内酯乙二硫醇缩酮(10); 10与5-溴-2-氯-4′-乙氧基二苯甲烷经亲核加成反应制得甲基糖苷(12); 12在BF3·Et2O催化下经Et3SiH还原、AlCl3脱去苄基、再经PhI(CF3CO2)2氧化脱除乙二硫醇保护基合成了SGLT2抑制剂3-羰基达格列净,共13步反应,总收率9%,该合成路线包含了11个新化合物的合成,其结构经1H NMR, 13C NMR, IR和HR-ESI-MS表征。  相似文献   

2.
<正>A new alkylene dihydrofuran glycoside(1) was isolated from the root bark ofMorus alba L.,along with moracin M-3′-O-β-D-glucopyranoside (2),and moracin M-6,3′-di-O-β-D-glucopyranoside(3).Compound 1 was identified as 2-methylene-3-methoxy-2, 5-dihydrofuran-4-O-β-D-glucopyranoside on the basis of chemical and spectroscopic data including 1D and 2D NMR spectral analysis.In addition,the antioxidant activity of 1 was evaluated using the 1,1-diphenyl-2-picrylhydrazyl(DPPH) and 2,2′-azinobis- 3-ethylbenzothiazoline-6-sulphonic acid(ABTS) assay.The IC_(50) values were 2.49 and 0.45 mg/mL,respectively.  相似文献   

3.
宽叶秦岭藤根部的化学成分   总被引:6,自引:0,他引:6  
通过正相和反相硅胶柱层析从宽叶秦岭藤根部乙醇提取物中分离纯化得到19个化合物,经波谱分析并结合化学方法鉴定了其结构,其中4个为新化合物,它们分别是3,5-二羟基二十烷酸羽扇豆醇酯(3),2-羟甲基-5-甲氧基苯基-O-β-D-吡喃葡萄糖甙(11),Δ5-孕甾烯-3β,20(S)-二醇-20-O-β-D-吡喃葡萄糖基(1→6)-β-D-吡喃葡萄糖甙(18,秦岭藤甙C)和Δ5-孕甾烯-3β,20(S)-二醇-3-O-β-D-吡喃葡萄糖基-20-O-β-D-吡喃葡萄糖基(1→6)-β-D-吡喃葡萄糖甙(19,秦岭藤甙D).  相似文献   

4.
A diterpenoid trisaccharide, smithoside A, and a saponin, smithoside B, as well as six known compounds, apigenin, apigenin-7-O-glucoside, daucosterol, shanzhiside methyl ester, 8-acetylshanzhiside methyl ester and acteoside, were isolated from Aster smithianus. On the basis of spectral evidence and chemical analytical results, smithosides A and B were identified as pimar-15(16)-β-ene-8β,11α-diol-3β-O-β-D-glucopyranosyl(1→3)-[β-glucopyranosyl(1→2)]-β-D-glucopyranoside and 2β,3β,16β,21β,23-pentahydroxy-12-ene-28 oleanoic acid lactone-3-O-β-D-glucopyranosyl(1→3)-β-D-glucopyranoside, respectively.  相似文献   

5.
两头尖的化学成分研究(Ⅱ)   总被引:3,自引:0,他引:3  
两头尖系毛莨科银莲花属植物多被银莲花(Anemone raddeanaRegel)的干燥根茎,分布于我国东北及山东等地.其味辛性热,具有祛风湿、消痈肿之功效.其总皂苷具有显著的抗肿瘤、抗炎、镇痛、镇静及抗惊厥作用.近年来,国内学者对其化学成分进行了较深入研究,已分离出近20种三萜皂苷类成分以及多种挥发油和多糖类成分.我们从两头尖中分离并鉴定了3个双糖链三萜皂苷化合物,其中化合物1为新化合物.化合物2和3为首次从两头尖中获得的已知化合物.  相似文献   

6.
黄花倒水莲皂甙Reinioside C在大鼠体内代谢产物的鉴定   总被引:3,自引:0,他引:3  
为了探讨五环三萜皂甙ReiniosideC在大鼠体内代谢产物的结构,单剂量口服ReiniosideC,5h后放血处死,用制备型高效液相色谱方法对血液和各脏器进行提取分离,从大肠内容物和粪中,分离得到了7种代谢产物.用FAB-MS,1H NMR和13C NMR方法鉴定了它们的结构.  相似文献   

7.
A new triterpenoid glycoside(1) and seven known triterpenoid glycosides, pseudoginsenoside RT2(2), yesanchinoside R2(3), vinaginsenoside R13(4), vinaginsenoside R8(5), notoginsenoside E(6), 6''-O-acetylginsenoside Re(7), 6"-O-acetylginsenoside Rb1(8), were isolated from the rhizomes of Panacis majoris. The new triterpenoid glycoside was elucidated as 3-O-[β-D-glucopyranosyl-(1→2)-β-D-(6'-O-ethyl)-glucuronopyranosyl]-oleanolic acid-28-O-β-D-glucopyranoside by extensive spectroscopic and phytochemical methods. Compounds 2-8 were obtained from the plant for the first time. Compounds 3 and 4 displayed good activities against adenosine diphosphate (ADP)-induced platelet aggregation, and compounds 1, 5, 6 and 8 showed moderate activities. Compound 6 exhibited moderate antiplatelet aggregation activity induced by arachidonic acid(AA).  相似文献   

8.
A new C27-steroidal glycoside from Ophiopogon japonicus   总被引:1,自引:0,他引:1  
A new C27-steroidal glycoside with three known compounds were isolated from the tuber of Ophiopogonjaponicus (Thunb.) Ker-Gawl. Based on the spectral analysis, including HRMS, 1H NMR, 13C NMR, DEPT, 1H-1H COSY, HMQC and HMBC, their chemical structures were determined as pennogenin-3-O-α-L-rhamnopyranosyl-(1→ 2)-β-D-xylopyranosyl-(1→ 4)-13-D-gluco- pyranoside (1), pennogenin-3-O-α-L-rhamnopyranosyl-(1→ 2)-β-D-glucopyranoside (2), ophiopojaponin C (3) and ophiopogonin D (4). 2007 Jian Zhong Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.  相似文献   

9.
四块瓦(Chloranthus Holostegius)为金粟兰科多年生草本植物,分布于云南、广西和贵州等地。全草有毒,具有抗菌、消炎、散瘀活血的功效。对四块瓦化学成份的研究尚未见报道,作者从其根的石油醚、乙醚和乙醇的提取液中,分离得到五个结晶单体。  相似文献   

10.
Upon UV irradiation in hexane at 243 K tricarbonyl-η5-cyclohexadienyl-manganese (1) and two equivalents of 2-butyne (2) or diphenylacetylene (4) yield in successive [5 + 2, 3 + 2] cycloadditions tricarbonyl-η2:2:1-1,2,3,10-tetramethyl-tricyclo[5.2.1.04,9]-deca-2,5-dien-10-yl-manganese (6), or tricarbonyl-η2:2:1-1,2,3,10-tetraphenyl-tricyclo[5.2.1.04,9]-deca-2,5-dien-10-yl-manganese (8), respectively. 3-Hexyne (3) reacts with 1 under the same conditions by successive [5 + 2, 3 + 2] cycloadditions and 1,4-H-shift to tricarbonyl-η2:2:1-1,2,3-triethyl-10-ethylidene-tricyclo[5.2.1.04,9]dec-2-en-5-yl-manganse (7). Identical products are also obtained when 1 is first irradiated in THF at 208 K and the thermolabile intermediate, dicarbonyl-η5-cyclohexadienyl-tetrahydrofurane-manganese (11), is treated with an excess of the alkynes 2–4. In contrast, bis(trimethylsily)acetylene (5) substitutes photochemically in 1 only a CO ligand to yield dicarbonyl-η5-cyclohexadienyl-η2-bis(trimethylsily)Acetylene-manganese (9). The crystal and molecular structure of 7 was determined by an X-ray diffraction analysis. Complex 7 crystallizes in the triclinic space group , a = 822.6(2) pm, B = 882.5(2) pm, C = 1344.6(2) pm, = 92.36(2)°, β = 107.13(2)°, γ = 99.71(2)°, V = 0.9152(3) nm3, Z = 2. The complexes 6–9 were studied in solution by IR and NMR spectroscopy. The structures of 6,8 and 9 were elucidated from the NMR spectra. A possible formation mechanism for the complexes 6–9 will be discussed.  相似文献   

11.
<正>A unusual flavone glycoside named Shamimarin(1) and a new compound Acetoxy-8-methyl-chromen-2H-one(2) were isolated from aerial parts of Rhododendron lepidotum L.along with four known coumarins daphnin(3),daphnetin 8-O-β-D-glucopyrano-side (4),daphnetin(5) and umbelliferone(6).The structural elucidations were based on analyses of chemical and spectroscopic data by including ID and 2D NMR analyses.  相似文献   

12.
苷类化合物研究(Ⅰ)——天麻苷类似物的合成   总被引:4,自引:0,他引:4  
本文合成了16种天麻苷类似物,测定了它们的13CNMR和1HNMR。依据NMR数据,这些化合物的端基构型指定为β构型。  相似文献   

13.
两个非对映异构三萜皂甙的结构鉴定   总被引:7,自引:0,他引:7  
从合欢皮95%乙醇提取物中分得2个新三糖链九糖皂甙(1,2),经化学方法和光谱分析,将其结构分别鉴定为:3-O-[β-D-吡喃木糖基-(1→2)-β-D-吡喃阿拉伯糖基-(1→6)-β-D-葡萄糖基]-21-O-(6S)-2-反式-2,6-二甲基-6-O-[4-O-((6R)-2-反式-2,6-二甲基-6-O-β-D-吡喃鸡纳糖基-2,7-辛二烯酸基)-β-D-吡喃鸡纳糖基]-2,7-辛二烯酸基金合欢酸28-O-β-D-吡喃葡萄糖基-(1→3)-[α-L-呋喃阿拉伯糖基-(1→4)]-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡萄糖基酯(1)和3-O-[β-D-吡喃阿拉伯糖基-(1→2)-β-D-吡喃呋糖基-(1→6)-β-D-葡萄糖基]-21-O-(6S)-2-反式-2,6-二甲基-6-O-[4-O-((6S)-2-反式-2,6-二甲基-6-O-β-D-吡喃鸡纳糖基-2,7-辛二烯酸基)-β-D-吡喃鸡纳糖基]-2,7-辛二烯酸基金合欢酸28-O-β-D-吡喃葡萄糖基-(1→3)-[α-L-呋喃阿拉伯糖基-(1→4)]-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡萄糖基酯(2),分别命名为合欢皂甙J14(JulibrosideJ14)和合欢皂甙J15(JulibrosideJ15)  相似文献   

14.
Condensation of thiosemicarbazide or N(4)-ethylthiosemicarbazide with 1,2,8,9-tetraphenyl-3,7-diazanona-1,9-dione in the presence of copper(II) acetate in 96% ethanol leads to Δ6-5,6-diphenyl-5-methoxy-1,2,4-triazacyclohexene-3-thione, C16H15N3OS, or Δ6-4-methyl-5,6-diphenyl-5-ethoxy-1,2,4-triazacyclohexene-3-thione, C18H19N3OS. For C16H15N3OS the crystal data are monoclinic, P21/c, a=9.7780(7), b=8.5120(3), c=18.2210(13) Å, β=100.958(3)°, V=1488.89(16) Å3, and Z=4 in agreement with an earlier report. For C18H19N3OS the crystal data are orthorhombic, P212121, a=8.6940(3), b=12.9946(3), c=15.5139(5) Å, V=1752.68(9) Å3, and Z=4.  相似文献   

15.
合成了2个新配体4-(4-硫代乙酸)甲苯基-6-苯基-2,2'-联吡啶HC^N^N(PhCH2SCOCH3)(L3)和6-(4-硫代乙酸)甲苯基-2,2'-联吡啶 HC^N^N (CH2SCOCH3)(L5)及其发光的铂(Ⅱ)配合物ClPtC^N^N(PhCH2SCOCH3)(C3)和ClPtC^N^N(CH2SCOCH3)(C5). 通过1H NMR谱和质谱对它们的结构进行了表征, 采用X射线单晶衍射分析确定了C3的晶体结构. 利用紫外-可见吸收光谱、 发射光谱及激发态寿命测定研究了它们的光物理性质和电化学性质, 以及配合物作为光敏剂在光催化制氢中的应用. 通过系列配合物产氢效率的比较, 揭示了它们的产氢效率和激发态寿命的关系.  相似文献   

16.
Dibenzo[b,e]-7,7,8,8-tetraalkyl-7,8-disilabicyclo[2.2.2]octa-2,5-dienes (1: R = tBuCH2; 2: R = iPr) were prepared by the reaction of ClR2SiSiR2Cl with lithium anthracenide in 1,2-dimethoxyethane (DME) at room temperature. The structure of 1 was determined by X-ray crystallography. Crystal data for 1: monoclinic, rC2/c, A = 12.941(2), B = 14.601(1), C = 35.109(6) Å, β = 94.957(7)°, V = 6609(2) Å3, Z= 8, R = 0.048, Rw = 0.053 for 4037 reflections. Compounds 1 and 2 show the bathochromic shift of 1La and 1Lb bands in UV spectra and exhibit considerably low oxidation potentials due to effective σ-π conjugation. Compounds 1 and 2 form charge-transfer complexes with tetracyanoethylene (TCNE). In the case of 1, the charge-transfer complex (1: TCNE = 2: 1) could be isolated as crystals and the structure was determined by X-ray crystallography. Crystal data for the 1-TCNE complex: monoclinic, C2/c, A= 10.267(2), b = 36.077(4), C = 20.022(4) Å, β = 100.680(8)°, V = 7288(2) Å3, Z = 4, R = 0.045, Rw = 0.077 for 4120 reflections. The action of transition metal chlorides on 2 resulted in [4+2] cycloreversion to form CliPr2SiSiiPr2Cl and anthracene.  相似文献   

17.
报道了4个含苯甲酰胺取代的水杨醛亚胺配体: N-(2-苯甲酰胺苯基)-水杨醛亚胺(L1)、 N-(2-苯甲酰胺苯基)-3-甲基水杨醛亚胺(L2)、 N-(2-苯甲酰胺苯基)-3-叔丁基水杨醛亚胺(L3)和N-(2-苯甲酰胺苯基)-3,5-二溴水杨醛亚胺(L4)的合成, 采用 1H NMR和HRMS对其结构进行了表征. 在助催化剂甲基铝氧烷(MAO)作用下, 以L3与TiCl4·2THF为模型催化体系, 在最佳陈化条件(陈化温度为25 ℃, 陈化时间为30 min, 配体与TiCl4·2THF的摩尔比3∶1)下, 考察了L1~L4/TiCl4·2THF催化体系Al/Ti摩尔比、 反应时间、 反应温度和聚合压力, 以及配体结构等对乙烯聚合的影响. 结果表明, 随着在水杨醛骨架上氧原子邻位取代基位阻的增大, 催化体系的活性及所得聚乙烯的分子量均有增加, 其中以L3的催化活性最高, 达到224 kg PE/(mol Ti?h). 采用高温 1H NMR, 13C NMR, GPC-IR和DSC等对由不同配体L1~L4/TiCl4·2THF得到的聚乙烯样品的微观结构与热性能进行了分析与表征, 结果显示样品为线性高密度聚乙烯, Mn=5.9×10 4~11.9×10 4, 分子量分布(PDI)为21.9~72.1.  相似文献   

18.
Gaussian-2 ab initio calculations were performed to examine the six modes of unimolecular dissociation of cis-CH3CHSH+ (1+), trans-CH3CHSH+ (2+), and CH3SCH2+ (3+): 1+→CH3++trans-HCSH (1); 1+→CH3+trans-HCSH+ (2); 1+→CH4+HCS+ (3); 1+→H2+c-CH2CHS+ (4); 2+→H2+CH3CS+ (5); and 3+→H2+c-CH2CHS+ (6). Reactions (1) and (2) have endothermicities of 584 and 496 kJ mol−1, respectively. Loss of CH4 from 1+ (reaction (3)) proceeds through proton transfer from the S atom to the methyl group, followed by cleavage of the C–C bond. The reaction pathway has an energy barrier of 292 kJ mol−1 and a transition state with a wide spectrum of nonclassical structures. Reaction (4) has a critical energy of 296 kJ mol−1 and it also proceeds through the same proton transfer step as reaction (3), followed by elimination of H2. Formation of CH3CS+ from 2+ (reaction (5)) by loss of H2 proceeds through protonation of the methine (CH) group, followed by dissociation of the H2 moiety. Its energy barrier is 276 kJ mol−1. On both the MP2/6-31G* and QCISD/6-31G* potential-energy surfaces, the H2 1,1-elimination from 3+ (reaction (6)) proceeds via a nonclassical intermediate resembling c-CH3SCH2+ and has a critical energy of 269 kJ mol−1.  相似文献   

19.
Four structurally unprecedented aconitane-type C_(19)-diterpenoid alkaloid glycosides with isomeric arabinosyls, named aconicarmichosides A–D(1–4), were isolated from an aqueous extract of "fu zi", the lateral roots of Aconitum carmichaelii. Their structures were determined as neoline 14-O-a-and 14-O-b-L-arabinopyranosides(1 and 2) and 14-O-a-and 14-O-b-L-arabinofuranosides(3 and 4), by spectroscopic and chemical methods including 2D NMR experiments and acid hydrolysis. Compounds 1–4 represent the first examples of glycosidic diterpenoid alkaloids.  相似文献   

20.
采用多种色谱分离方法从柳叶五层龙(Salacia cochinchinensis Lour)的茎叶中分离得到5个化合物. 通过一维(1D)及二维核磁共振波谱(2D NMR), 包括核磁共振氢谱(1H NMR)、 核磁共振碳谱(13C NMR)、 异核单量子相关(HSQC)、 异核多键相关(HMBC)、 氢氢相关(1H-1H COSY)和旋转坐标中的欧沃豪斯增强光谱(ROESY), 以及红外光谱(IR)和电喷雾电离高分辨质谱(ESI-HRMS)等方法, 鉴定其结构分别为Salaciacochinoside A(1), 5'-O-3,4,5-trimethoxybenzoyl-β-D-apiofuranoside(2), 5-methoxy-anticerol A(3), 21α,30-dihydroxy-D∶A-friedooleanan-3-one(4)和21α,26-dihydroxyfriedelan-3-one(5). 化合物1~3为新化合物. α-葡萄糖苷酶抑制活性测试结果显示, 化合物1和3对α-葡萄糖苷酶具有显著的抑制作用, 其IC50值分别为0.32和0.59 μmol/L; 化合物2, 4和5未表现出α-葡萄糖苷酶抑制活性.  相似文献   

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