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Synthesis and Characterization of Yttrium Aluminum Garnet Phosphors for White Light Emitting Diodes
No full text白光發光二極體(white light emitting diode; WLED)自1996年由日本日亞化學公司以藍光晶片為基礎搭配釔鋁石榴石(yttrium aluminum garnet; YAG)之發黃光螢光粉得白光而正式商品化至今發展近十年，期間除各式之螢光粉體與晶片之搭配組合已有廣泛之研究與報導外，白光發光二極體之應用市場亦同時有多樣之發展。此外，進一步利用紫外光二極體激發不同螢光粉之研究亦相繼展開，未來利用白光發光二極體作為人類理想之照明燈源更期望於2010年達到。
然而，綜觀目前產生白光之搭配方式上，使用兩種以上之螢光粉體於實際光能轉換效率與粉體個別劣化產生之缺點，以及使用紫外光發光二極體做為激發光源所遭遇之二極體效率之瓶頸與螢光粉體對於紫外光吸收效率低之缺點。目前最穩定之白光產生方式仍以上述之藍光晶片搭配發黃光螢光粉方式為最常見，然而欲以此結構作為照明光源，粉體之光能轉換效率及其對於激發光源之調變性仍須進一步之改善。
本研究之目的乃利用鋱離子(Tb3+)取代於釔鋁石榴石之結構，除作為一增感劑，更進一步取代釔離子(Y3+)之結構形成鋱-釔鋁石榴石之主體晶格，進而改變發光中心之發射光譜特性。此外，本研究亦於粉體合成過程利用助熔劑之添加改變晶體形成過程，進而改善鋱添加粉體其發射強渡下降之缺點，使其發光強度可優於原釔鋁石榴石，且改善後之粉體表面型態，更適合於實際發光二極體之製作。本研究亦利用真空紫外光、低溫光譜儀與固態核磁共振儀之分析，進而探討鋱-釔鋁石榴石之能量轉換與躍遷之機制。
於本研究中所使用之分析方法為以X-光粉末繞射儀(X-ray diffraction; XRD)鑑定樣品之純度及其長程有序晶體結構；利用光激發光光譜儀(photoluminescence; PL)分析螢光粉之激發光譜及放射光譜特性，並將發射光譜以程式轉換為其色度座標；利用同步輻射真空紫外光源(vacuum ultra-violet; VUV)分析螢光粉於高能量激發之發光特性與低溫光譜儀(low temperature PL)分析螢光粉於低溫下激發之放射光譜，並藉以研究其能量轉換機制；以掃瞄式電子顯微鏡(scanning electron microscope; SEM)進行樣品表面型態分析及觀察其粒徑大小之差異性；以熱重分析及差式掃描熱分析 [thermo gravimetric analysis (TGA) and differential scanning calorimetric (DSC)]分析樣品熱分解過程之重量變化及化學反應過程；以固態核磁共振儀 (solid state nuclear magnetic resonance; S. S. NMR)決定樣品中特定元素之配位環境。本研究部分成果已發表於J. Electrochem. Soc. [152, J41 (2005)]、申請四件專利及投稿三篇論文於國際期刊(Chem. Mater.；J. Electrochem. Soc.；J. Lumin.)。It has been about 10 years since the company of Nichia in Japan realized the white light emitting diodes (WLEDs) by combination of the blue chip with yttrium aluminum garnet (YAG) which emits yellow color. In the past years, various methods were reported in the use of different chips and phosphors and the applications of WLEDs were also noticed in various fields. At the same time, the studies of the UV-LED with phosphors were carried out. It is expected to use the WLEDs as the ideal lighting device in 2010.
Eventhough various methods have been developed over the period of time for the construction of WLEDs, there still exists some disadvantages. Firstly, preparation of LEDs by mixing more than two different phosphors results in different levels of energy transfer efficiency and decay rate for every phosphor. Secondly, the difficulties in the improvement of UV-LED efficacy still need been examined. Even now the most stable way to produce WLEDs is the combination of the blue chip and phosphors emitting yellow light as mentioned above. Nevertheless, the energy transfer efficiency and the absorbance to different excited energy of phosphors are needed to be improved in present time.
In this work, we substituted the Tb3+ into the crystal of the yttrium aluminum garnet structure and investigated its properties. Except being as sensitizers, Tb3+ ions substitute Y3+ to form the host as the terbium-yttrium aluminum garnet structure, which influenced the emission character of activators. We also introduced fluxes in the synthesis of phosphors to change crystallite-formation processes. The flux addition during synthesis enhances the emission efficiency of phosphors which is superior to commercially available phosphor. We proposed the possible mechanisms for the transition and energy-transfer process of electrons by the investigation of VUV-PL spectra, low-temperature PL spectra, and solid state NMR spectra.
In this work, we utilized X-ray diffraction (XRD) to investigate the crystal phase and long range ordering. In regard to the luminescent properties such as excitation and emission spectra, photoluminescence spectrometer (PL) was used. We also investigated luminescent properties by PL spectra excited by VUV synchrotron radiation source and the PL spectra at low temperature to study the energy transfer processes. The SEM was used to analysis the particle size and morphology of phosphors. The TGA/DSC analyses were performed to examine the weight lost process and chemical reactions during the heat treatment. We also utilized the SS.-NMR to investigate the coordination environments of critical elements. Some results of this study are already published in J. Electrochem. Soc. [152, J41 (2005)]. Three more manuscripts are under preparation (Chem. Mater.; J. Electrochem. Soc.; J. Lumin.) and four patents have been filed from the outcome of results.第一章 序論 1
1.1人類照明歷史 1
1.1.1 白熾燈泡與其發光原理 2
1.1.2 日光燈與其發光原理 2
1.1.3 各種照明設備 3
1.2 白光發光二極體（White Light Emitting diodes; WLEDs） 5
1.2.1 白光發光二極體發展 5
1.2.2 白光發光二極體之種類 6
1.3 白光發光二極體市場現況與未來展望 10
1.4 螢光粉之發光原理 12
1.4.1 螢光現象 12
1.4.2 史托克位移與卡薩定則 14
1.4.3 法蘭克-康頓原理(Frank-Conden Principle) 14
1.4.5 固態螢光材料 16
1.4.6 激發態反應 19
1.4.7 選擇率 20
1.5晶體與晶格場 22
1.5.1 固態晶體 22
1.5.2 晶格缺陷 22
1.5.3 晶格場 25
1.5.4 電子雲擴張效應 26
1.5.5 活化中心電子躍遷能量變化 27
1-6 色彩 28
1.6.1 發光強度之表示 28
1.6.2 CIE色度座標 29
1.6.3 色溫與演色性 30
1.7具釔鋁石榴石結構之螢光粉 32
1.7.1 晶體結構 32
1.7.2 異種離子添加 35
1.8 核磁共振原理簡介 37
1.8.1 自然界之核自旋現象 37
1.8.2 核磁共振 38
1.8.3 化學位移 40
1.8.4 譜線寬化 40
1.9 文獻回顧 44
1.10 研究目的 49
第二章 樣品合成及儀器分析原理 50
2.1 化學藥品 50
2.2 樣品之製備 51
2.2.1實驗流程 51
2.2.2 (Y2.3-xTbxCe0.05Gd0.65)Al5O12之合成 52
2.2.3 (Y2.95-xTbxCe0.05)Al5O12之合成 52
2.2.4 (Tb2.45Y0.5Ce0.05)Al5O12添加助融劑 52
2.2.5 (Y2.3Ce0.05Gd0.65)Al5O12與(Y2.95Ce0.05)Al5O12添加助融劑之合成 53
2.3 樣品鑑定分析 54
2.4粉末X光繞射儀 55
2.4.1 X光繞射原理 55
2.4.2 結構精算 57
2.4.3 XRD實驗儀器 59
2.5 光激發光譜儀(Photoluminescence; PL) 61
2.5.1 激發光譜與發射光譜 61
2.5.2 PL實驗儀器 63
2.5.3 真空紫外光分析 65
2.6 熱重分析-式差掃描熱量分析儀(Thermogravimetric Analysis-Differential Scanning Calorimetry; TGA/DSC ) 67
2.6.1熱重分析與差式掃描熱量分析簡介 67
2.6.2 熱分析實驗儀器 70
2.7固態核磁共振儀 71
2.7.1 魔角旋轉(Magic Angle Spinning; MAS) 71
2.7.2 三重量子魔角旋轉(Triple Quantum MAS; TQMAS) 73
2.7.3 NMR實驗儀器 74
2.8掃描式電子顯微鏡(Scanning Electron Microscope; SEM) 76
2.8.1 SEM 原理簡介 76
2.8.2 SEM 實驗儀器 76
第三章 結果與討論 78
3.1 Y2.3-xTbxCe0.05Gd0.65)Al5O12 與(Y2.95-xTbxCe0.05)Al5O12特性分析 78
3.1.1 (Y2.3-xTbxCe0.05Gd0.65)Al5O12晶體結構與光譜分析 78
3.1.2 (Y2.95-xTbxCe0.05)Al5O12光譜分析 87
3.1.3 低溫光譜之特性分析 91
3.1.4 放光特性之討論 98
3.1.5 利用固態核磁共振儀之探討 99
3.2 (Y2.3-xTbxCe0.05Gd0.65)Al5O12真空紫外光光譜分析 101
3.2.1真空紫外光之激發光譜與發射光譜分析……………..101
3.2.2 Tb3+、Y3+與Ce3+於能量轉移過程之影響 104
3.3助熔劑效應 107
3.3.1 (Y0.5Tb2.45Ce0.5)Al5O12助熔劑添加之晶體結構與光譜特性分析 107
3.3.2 (Y2.3Gd0.65Ce0.05)Al5O12與(Y2.95Ce0.05)Al5O12助熔劑添加之晶體結構與光譜特性分析 111
3.3.3 助熔劑效應對晶體表現形態之影響 116
3.3.4 (Y0.5Tb2.45Ce0.5)Al5O12助熔劑效應之熱重分析……… 119
3.4 氮化矽添加於Y3Al5O12:Ce 123
3.4.1 晶體結構與光譜特性分析 123
3.4.2 固態核磁共振特性分析 126
第四章 結論 135
第五章 參考文獻 138
附件(發表論文) 143
表目錄
表1-1 電光源應用分類 4
表1-2 常見白光發光二極體用螢光粉之種類 9
表1-3 常見原子與其基態之自旋量子數 37
表2-1 本研究所使用之藥品 50
表3-1 (Y1.15Tb1.15Ce0.05Gd0.65)Al5O12樣品之各項原子結構參數 81
表3-2擬合之不同能階之存活時間參數與最小平方差 97
表3-3三種主體晶格組成之助熔劑效應比較 115
表3-4 熱處理過程之理論重量損失計算 121
表3-5利用Massiot方法分析所得之化學位移、二階四極矩能量常數與各環境所佔之比例等參數 130
圖目錄
圖1-1 愛迪生發明之人類第一座電燈泡 1
圖1-2三晶片型白光LED結構示意 7
圖1-3 三種常見白光LED之比較 8
圖1-4 2004年預估未來白光LED之發展潛力 11
圖1-5 各種白色照明裝置之效率 11
圖1-6 物質吸光與放光過程電子轉移路徑(Jabłoński diagram) 13
圖1-7法蘭克-康頓原理之位能曲線示意 15
圖1-8 主體晶格(H)與活化中心(A)發光過程 17
圖1-9主體晶格(H)、增感劑(S)與活化中心(A)發光過程 17
圖1-10 五種螢光電子躍遷機制模型 18
圖1-11 螢光物質之激發態反應能量競爭 20
圖1-12 能量與缺陷濃度之關係變化過程 23
圖1-13 d軌域於八面體晶格場之能階分裂 26
圖1-14 晶格場理論與電子雲擴張效應對f-d躍遷之影響 27
圖1-15 CIE1931色度座標 30
圖1-16 (a)YAG基本結構，(b)對稱元素操作過程 34
圖1-17 原子核與電子間磁性交互作用 38
圖1-18 外加磁場與原子核precession之關係 39
圖1-19 原子核j與k之偶極-偶極作用力 41
圖1-20 非均勻電荷分布之四極矩作用 42
圖1-21專利申請數量與時間之關係 48
圖2-1 三步驟固態反應流程圖 51
圖2-2 X光射線之白光光譜與特性光譜 56
圖2-3 Rietveld結構精算圖 58
圖2-4 X光粉末繞射儀旋轉中心示意圖 60
圖2-5 本研究所使用之X光粉末繞射儀(PANalytical X’Pert PRO XRD) 60
圖2-6 螢光體激發光譜之量測過程 62
圖2-7 螢光體發射光譜之量測過程[ 62
圖2-8 光激發光譜儀構造 64
圖2-9 光激發光譜儀(FluoroMax-3)儀器外觀 64
圖2-10 真空紫外光儀器系統 66
圖2-11 熱重分析儀之結構示意圖 68
圖2-12 微分熱分析法(differential thermal analysis; DTA)圖 69
圖2-13 儀器實際外觀，左圖為TGA (TGA 2950)分析儀器右圖則DSC測量所使用之設備(Netzsch DSC 404) 70
圖2-14 魔角旋轉條件 71
圖2-15 空間座標與實驗室座標之關係 73
圖2-16脈衝過程與能階之三重量子魔角旋轉過程 74
圖2-17 核磁共振儀儀器(Bruker DSX-300)外觀 75
圖2-17掃描式電子顯微鏡儀器(Philips XL40 SEM)外觀 77
圖3-1 (Y2.3-xTbxCe0.05Gd0.65)Al5O12 (x = 0、0.575、1.15、1.725與2.3)於三步驟固態反應法之XRD圖譜 79
圖3-2 (Y1.15Tb1.15Ce0.05Gd0.65)Al5O12樣品X光粉末繞射結構經算結果 81
圖3-3 (Y2.3-xTbxCe0.05Gd0.65)Al5O12樣品之Tb3+取代量與晶格長度之關係圖 82
圖3-4 (Y1.15Tb1.15Ce0.05Gd0.65)Al5O12樣品之激發與發射光譜圖 83
圖3-5 (Y2.3-xTbxCe0.05Gd0.65)Al5O12( x = 0、0.575、1.15、1.725與2.3)之激發光譜圖 84
圖3-6 (Y2.3-xTbxCe0.05Gd0.65)Al5O12( x = 0、0.575、1.15、1.725與2.3)之發射光譜圖 85
圖3-7 發射光譜強度與Tb3+摻雜含量之關係，其中本研究以商用之粉體強度作為標準，其強度以100定之 85
圖3-8 (Y2.3-xTbxCe0.05Gd0.65)Al5O12系列粉體CIE色度座標 86
圖 3-9 (Y2.95-xTbxCe0.05)Al5O12(x = 0、0.5、1.15、1.8與2.45)之激發光譜圖 87
圖 3-10 (Y2.95-xTbxCe0.05)Al5O12 (x = 0、0.5、1.15、1.8與2.45)之發射光譜圖 88
圖3-11 兩系列螢光粉體於Tb3+摻雜過程之最強發光波長之總體比較 90
圖3-12 為兩系列螢光粉體於Tb3+摻雜過程之最強發光波長發光強度總體比較 90
圖3-13 Y3Al5O12:Ce(YAG)與Tb3Al5O12(TAG)低溫(13K)光激發光譜圖 91
圖3-14 YAG:Ce於13 K之發射光譜 93
圖3-15 TAG:Ce於13 K之發射光譜 93
圖3-16 Ce3+於YAG與TAG兩主體晶格感受相異之晶體場穩定作用(crystal field stability; CFS)，而相同之自旋-軌域偶合作用(spin-orbital interaction) 94
圖3-17 Ce3+於YAG與TAG兩主體晶格位能曲線之差異與電子轉移過程 94
圖3-18存活時間之量測，分別為YAG:Ce設定於(a) 400 nm、(B) 525、(C)570 nm之放光波長與TAG:Ce設定於(D) 400 nm、(E) 535、(F)585 nm之放光波長 96
圖3-19於室溫以325 nm激發之發射光譜圖 97
圖3-20 (Y2.95-xTbxCe0.05)Al5O12(x =0.5、1.15、1.8與2.45)之27Al固態核磁共振結果 100
圖3-21 (Y1.15Tb1.15Ce0.05Gd0.65)Al5O12於高能量範圍之激發光譜圖，以543 nm之波長作為發射波長 102
圖3-22 (Y1.15Tb1.15Ce0.05Gd0.65)Al5O12發射光譜圖 102
圖3-23 (Y2.3-xTbxCe0.05Gd0.65)Al5O12( x = 0、0.575、1.15、1.725與2.3)之激發光譜圖 103
圖3-24 (Y2.3-xTbxCe0.05Gd0.65)Al5O12( x = 0、0.575、1.15、1.725與2.3)之激發光譜圖 103
圖3-25 Tb3+、Ce3+與主體晶格之能階關係與其電子轉移過程 106
圖3-26 (Y0.5Tb2.45Ce0.5)Al5O12加入三種不同組成之助熔劑未經洗滌過程XRD圖譜 108
圖3-27 (Y0.5Tb2.45Ce0.5)Al5O12加入三種不同組成之助熔劑經洗滌過程之XRD圖譜 109
圖3-28 (Y0.5Tb2.45Ce0.5)Al5O12加入三種不同組成之助熔劑激發光譜圖 110
圖3-29 (Y0.5Tb2.45Ce0.5)Al5O12加入三種不同組成之助熔劑發射光譜圖 111
圖3-30 (Y2.95Ce0.05)Al5O12與 (Y2.3Gd0.65Ce0.05)Al5O12兩螢光粉體加入助熔劑之XRD圖譜 112
圖3-31 (Y2.95Ce0.05)Al5O12與 (Y2.3Gd0.65Ce0.05)Al5O12兩螢光粉體加入助熔劑之粉體與未加入助熔劑粉體之激發光譜圖 111
圖3-32 (Y2.95Ce0.05)Al5O12與 (Y2.3Gd0.65Ce0.05)Al5O12兩螢光粉體加入助熔劑之粉體與未加入助熔劑粉體之發射光譜圖 114
圖3-33 (Y0.5Tb2.45Ce0.5)Al5O12樣品(點E)因助熔劑效應而增強其發光強度 116
圖3-34 (Tb2.45Y0.5Ce0.05)Al5O12之SEM 照片，分別於合成過程加入：(a) no fluxes，(b) BaF2，(c) H3BO3與(d) H3BO3/ BaF2 117
圖3-35 SEM 照片，分別為(a) YAG:Ce,Gd (no fluxes)、(b) YAG:Ce,Gd (fluxes)、(a) YAG:Ce (no fluxes)與(d) YAG:Ce (fluxes) 120
圖3-36 (Tb2.45Y0.5Ce0.05)Al5O12樣品之TGA熱重分析 121
圖3-37 Tb2.45Y0.5Ce0.05)Al5O12樣品之DSC熱分析圖 122
圖3-38 Y3Al5O12:Ce加入兩不同含量之Si3N4之XRD光譜圖 124
圖3-39 Y3Al5O12:Ce加入兩不同含量之Si3N4之激發光譜圖 125
圖3-40 Y3Al5O12:Ce加入兩不同含量之Si3N4之發射光譜圖 126
圖3-41 Y3Al5O12:Ce粉體之 27Al之固態核磁共振光譜，其中加入Si3N4含量分別為0 、0.2與0.4 127
圖3-42 27Al之三重量子魔角旋轉(TQ-MAS)之二維圖譜 129
圖3-43校正位移(shear)後之27Al三重量子魔角旋轉(TQ-MAS)二維圖譜 130
圖3-44 Y3Al5O12:Ce加入不同含量之Si3N4之XRD與可能之雜相標準光譜圖 132
圖3-45 YAG:Ce + x Si3N4取代量與晶格常數之關係圖 133
圖3-46 合成具配方Y2(Si1.55Al0.45)O7之樣品XRD光譜圖 13
Study on the Flavonoid Constituents of Machilus japonica Sieb. & Zucc. var. kusanoi (Hayata) Liao
No full text在本研究中，一開始依據活性測試結果為導向之分離 (bioassay-guided separation)，尋找對甲型葡萄糖水解酶(α-glucosidase)有抑制作用的化合物。選定樟科楨楠屬植物大葉楠Machilus japonica Sieb. & Zucc. var. kusanoi (Hayata) Liao (Lauraceae)葉部為研究目標，首先將酒精萃取物，經極性劃分為二氯甲烷、乙酸乙酯、正丁醇和水可溶四部分，並針對正丁醇可溶部分進行研究。但發現活性部分不強且成分散置，因此以一般方法進行正丁醇可溶部分之成分研究，經分離得到八個屬於類黃酮成分的化合物：2'-O-α-L-Rhamnopyranosyl isovitexin (1)，2"-O-α-L-Rhamnopyranosyl vitexin (2)，Apigenin 4'-O-β-D-glucopyranoside (3)，化合物4，化合物5，化合物6，Quercetin-3-O-β-D-galactoside (7)和Quercetin-3-O-β-D-glucoside (8)。其中化合物1到6屬於黃酮 (flavones)，而化合物7和8則屬於黃酮醇 (flavonols)，化合物4、5、6則為新架構天然物。
這一系列化合物對α-glucosidase的抑制效果並不理想，前六個化合物中，僅化合物3、5、6在100 μg/mL呈現強弱不一的抑制活性，抑制百分比依序為64.7%、18.7%及93.7%，然而在10 μg/mL濃度時皆無活性。Guided by bioassay against α-glucosidase, the active constituents of the leaves extract of Machilus japonica Sieb. & Zucc. var. kusanoi (Hayata) Liao (Lauraceae) were investigated in this study. Several attempts were made to concentrate the active fractions from this approach. However, it was found that the activity was not strong in each fraction. Then, the aim of this study turned to the separation of chemical constituents of the polar fractions via various chromatographic techniques. The effects led to the identification of eight compounds, 2'-O-α-L-rhamnopyranosyl isovitexin (1), 2"-O-α-L-rhamnopyranosyl vitexin (2), apigenin 4'-O-β-D-glucopyranoside (3), compound (4), compound (5), compound (6), quercetin-3-O-β-D-galactoside (7) and quercetin-3-O-β-D-glucoside (8). Compounds 1-6 belong to flavones and compounds 7-8 belong to flavonols. In addition, compounds 4-6 are disclosed to be new natural products, possessing a novel skeleton.
These compounds exhibit weak inhibitory activity against α-glucosidase. Of these compounds tested (1-6), compounds 3, 5 and 6 exhibit 64.7 %, 18.7 % and 93.7 % of inhibitory activity, respectively, at a concentration level of 100 μg/mL; but no activity was obsevered for each compound at 10 μg/mL level.總目錄
口試委員會審定書 i
誌謝 ii
中文摘要 iii
Abstract iv
目錄 I
流程圖目錄 Ⅱ
表目錄 Ⅱ
圖目錄 Ⅲ
參考文獻 86
附圖 93
目錄
壹、序論 1
1-1研究目的 1
1-2植物簡介 3
1-3 Machilus屬植物成分之文獻回顧 4
1-4 α-Glucosidase inhibitors簡介 17
1-5 類黃酮成分簡介 19
1-5-1 命名 19
1-5-2 生物活性 21
貳、實驗儀器與材料 22
2-1理化性質測定儀器 22
2-2成分分離之儀器及材料 22
2-3 試劑與溶媒 23
2-4 甲型葡萄糖水解酶之活性試驗 (α-Glucosidase assay) 所用試劑與儀器 24
參、實驗結果與討論 25
3-1 活性導向分離條件探索 25
3-2 類黃酮成分之分離及結構解析 30
3-2-1 2'-O-α-L-Rhamnopyranosyl isovitexin (1)之結構解析 32
3-2-2 2"-O-α-L-Rhamnopyranosyl vitexin (2)之結構解析 38
3-2-3 Apigenin 4'-O-β-D-glucopyranoside (3)之結構解析 42
3-2-4 化合物4之結構解析 45
3-2-5 化合物5之結構解析 51
3-2-6 化合物6之結構解析 55
3-2-7 化合物4 ~ 6之可能生合成途徑 60
3-2-8 Quercetin-3-O-β-D-galactoside (7)之結構解析 61
3-2-9 Quercetin-3-O-β-D-glucoside (8)之結構解析 64
3-3 化合物1-6活性測試結果 67
3-4 一系列同分異構物分離之困難點討論 68
3-5 結論 70
肆、實驗部分 71
4-1 甲型葡萄糖水解酶之活性試驗 (α-Glucosidase assay) 71
4-1-1 原理 71
4-1-2 酵素活性單位 71
4-1-3 實驗方法 71
4-2大葉楠葉部成分之萃取與分離 74
4-3 化合物分離 75
4-3-1 活性導向部分的分離 76
4-3-2 2'-O-α-L-Rhamnopyranosyl isovitexin (1)的分離和2"-O-α-L-Rhamnopyranosyl vitexin (2)的分離 78
4-3-3 Apigenin 4'-O-β-D-glucopyranoside (3)的分離 79
4-3-4 化合物4的分離 79
4-3-5 化合物5的分離 80
4-3-6 化合物6的分離 80
4-3-7 Quercetin-3-O-β-D-galactoside (7)和Quercetin-3-O-β-D-glucoside (8)的分離 81
4-3-8 化合物1-8之物理數據 82
流程圖目錄
Scheme 1. The possible biosynthetic pathway of compounds 4 ~ 6. 60
Scheme 2. The principle of α-glucosidase assay. 71
Scheme 3. Fractionation of EtOH extract of Machilus kusanoi Hayata. 74
Scheme 4. Separation process of compounds 1-8 from n-BuOH soluble fraction. 75
表目錄
Table 1. Chemical constituents from the Machilus plants (Lauraceae) 4
Table 2. α-glucosidase inhibitors in clinical use. 17
Table 3. 1H (400 MHz) and 13C NMR (100 MHz) data and HMBC correlation of compound 1 (CD3OD) 37
Table 4. 1H (400 MHz) and 13C NMR (100 MHz) data and HMBC correlation of compound 2 (CD3OD) 41
Table 5. 1H (400 MHz)and 13C NMR (50 MHz) of compound 3 (CD3OD) and the reported data for apigenin 4'-O-β-D-glucopyranoside and 43
Table 6. 1H (400 MHz) and 13C NMR (100 MHz) data and HMBC correlation of compound 4 (CD3OD) 49
Table 7. 1H (400 MHz) and 13C NMR (100 MHz) data and HMBC correlation of compound 5 (CD3OD) 53
Table 8. 1H (400 MHz) and 13C NMR (100 MHz) data and HMBC correlation of compound 6 (CD3OD) 58
Table 9. 1H (400 MHz) and 13C NMR (50 MHz) of compound 7 (CD3OD) and 62
the reported data for quercetin-3-O-β-D-galactoside (C5D5N, 400 MHz) 62
Table 10. 1H (400 MHz) and 13C NMR (100 MHz) of compound 8 (CD3OD) and the reported data for quercetin-3-O-β-D-glucoside (CD3OD, 400 MHz) 65
Table 11. Separation result of compounds 1 and 2 by Sephadex LH-20 [MeOH-H2O system]. 68
圖目錄
Figure 1. 大葉楠Machilus japonica Sieb. & Zucc. var. kusanoi (Hayata) Liao (Lauraceae) 2
Figure 2. Structure of α-glucosidase inhibitors in clinical use. 18
Figure 3. 1H-NMR assignment for compound 1 (CD3OD, 400 MHz) 34
Figure 4. 13C-NMR assignment for compound 1 (CD3OD, 100 MHz) 35
Figure 5. Key NOESY correlations of compound 1 (CD3OD, 400 MHz) 35
Figure 6. Key COSY correlations of compound 1 (CD3OD, 400 MHz) 36
Figure 7. Key HMBC correlations of compound 1 (CD3OD, 400 MHz) 36
Figure 8. 1H-NMR assignment for compound 2 (CD3OD, 400 MHz) 39
Figure 9. 13C-NMR assignment for compound 2 (CD3OD, 100 MHz) 39
Figure 10. Key COSY correlations of compound 2 (CD3OD, 400 MHz) 40
Figure 11. Key HMBC correlations of compound 2 (CD3OD, 400 MHz) 40
Figure 12. 1H-NMR assignment for compound 3 (CD3OD, 400 MHz) 44
Figure 13. 13C-NMR assignment for compound 3 (CD3OD, 50 MHz) 44
Figure 14. 1H-NMR assignment for compound 4 (CD3OD, 400 MHz) 47
Figure 15. 13C-NMR assignment for compound 4 (CD3OD, 100 MHz) 47
Figure 16. Key COSY correlations of compound 4 (CD3OD, 400 MHz) 48
Figure 17. Key NOESY correlations of compound 4 (CD3OD, 400 MHz) 48
Figure 18. Key HMBC correlations of compound 4 (CD3OD, 400 MHz) 50
Figure 19. 1H-NMR assignment for compound 5 (CD3OD, 400 MHz) 52
Figure 20. 13C-NMR assignment for compound 5 (CD3OD, 100 MHz) 52
Figure 21. Key HMBC correlations of compound 5 (CD3OD, 400 MHz) 54
Figure 22. 1H-NMR assignment for compound 6 (CD3OD, 400 MHz). 56
Figure 23. 13C-NMR assignment for compound 6 (CD3OD, 100 MHz) 56
Figure 24. Key COSY correlations of compound 6 (CD3OD, 400 MHz) 57
Figure 25. Key NOESY correlations of compound 6 (CD3OD, 400 MHz) 57
Figure 26. Key HMBC correlations of compound 6 (CD3OD, 400 MHz) 59
Figure 27. 1H-NMR assignment for compound 7 (CD3OD, 400 MHz) 63
Figure 28. 13C-NMR assignment for compound 7 (CD3OD, 50 MHz) 63
Figure 29. 1H-NMR assignment for compound 8 (CD3OD, 400 MHz) 66
Figure 30. 13C-NMR assignment for compound 8 (CD3OD, 100 MHz) 66
Figure 31. HPLC sepectrum of Fr. D-2-12 69
Figure 32. 96孔微量測試盤上各組測試樣品的排列情形 73
Figure 33. CD spectra of compounds 1, 2 and 3 (MeOH)…………………………..94
Figure 34. CD spectra of compounds 4, 5 and 6 (MeOH).…………………………..95
Figure 35. CD spectra of compounds 7 and 8 (MeOH).……………………………..96
Figure 36. UV spectra of compounds 1, 2 and 3 (MeOH). ………….……………... 97
Figure 37. UV spectra of compounds 4, 5 and 6 (MeOH). ………….……………....98
Figure 38. UV spectra of compounds 7 and 8 (MeOH). ………….………………....99
Figure 39. IR spectra of compounds 4, 5 and 6. …………….…….………………..100
Figure 40. MS and MS/MS spectra of compound 1 (MeOH). ..……………………101
Figure 41. MS and MS/MS spectra of compound 2 (MeOH)…………………...….102
Figure 42. MS and MS/MS spectra of compound 3 (MeOH)…………………...….103
Figure 43. MS and MS/MS spectra of compound 4 (MeOH)…………………...….104
Figure 44. MS and MS/MS spectra of compound 5 (MeOH)………………...….....105
Figure 45. MS and MS/MS spectra of compound 6 (MeOH)...………………...…..106
Figure 46. MS and MS/MS spectra of compound 7 (MeOH)…………………...….107
Figure 47. MS and MS/MS spectra of compound 8 (MeOH).. ..………………...…108
Figure 48. 1H-NMR spectrum of compound 1 (CD3OD, 400 MHz). …………...…109
Figure 49. 13C-NMR spectrum of compound 1 (CD3OD, 100 MHz). ……………..110
Figure 50. COSY spectrum of compound 1 (CD3OD, 400 MHz). ………….......….111
Figure 51. NOESY (1) spectrum of compound 1 (CD3OD, 400 MHz). ………..….112
Figure 52. NOESY (2) spectrum of compound 1 (CD3OD, 400 MHz). ………..….113
Figure 53. HMQC (1) spectrum of compound 1 (CD3OD, 400 MHz). …………....114
Figure 54. HMQC (2) spectrum of compound 1 (CD3OD, 400 MHz). ……..……..115
Figure 55. HMQC (3) spectrum of compound 1 (CD3OD, 400 MHz). ……..…......116
Figure 56. HMBC (1) spectrum of compound 1 (CD3OD, 400 MHz). ………….....117
Figure 57. HMBC (2) spectrum of compound 1 (CD3OD, 400 MHz). ……..……...118
Figure 58. HMBC (3) spectrum of compound 1 (CD3OD, 400 MHz). …………….119
Figure 59. 1H-NMR spectrum of compound 2 (CD3OD, 400 MHz). …………..….120
Figure 60. 13C-NMR spectrum of compound 2 (CD3OD, 100 MHz). ………..……121
Figure 61. COSY (1) spectrum of compound 2 (CD3OD, 400 MHz). ………….….122
Figure 62. COSY (2) spectrum of compound 2 (CD3OD, 400 MHz). ………….….123
Figure 63. COSY (3) spectrum of compound 2 (CD3OD, 400 MHz). ………..……124
Figure 64. HMQC (1) spectrum of compound 2 (CD3OD, 400 MHz). ………..…..125
Figure 65. HMQC (2) spectrum of compound 2 (CD3OD, 400 MHz). …………....126
Figure 66. HMQC (3) spectrum of compound 2 (CD3OD, 400 MHz). …………....127
Figure 67. HMBC (1) spectrum of compound 2 (CD3OD, 400 MHz). ………..…...128
Figure 68. HMBC (2) spectrum of compound 2 (CD3OD, 400 MHz). ………..…...129
Figure 69. HMBC (3) spectrum of compound 2 (CD3OD, 400 MHz). ………..…...130
Figure 70. 1H-NMR spectrum of compound 3 (CD3OD, 400 MHz). ………..…….131
Figure 71. 13C-NMR spectrum of compound 3 (CD3OD, 50 MHz). ………..…..…132
Figure 72. 1H-NMR spectrum of compound 4 (CD3OD, 400 MHz). ………..….....133
Figure 73. 13C-NMR spectrum of compound 4 (CD3OD, 100 MHz). ………..…....134
Figure 74. COSY (1) spectrum of compound 4 (CD3OD, 400 MHz). ………..…....135
Figure 75. COSY (2) spectrum of compound 4 (CD3OD, 400 MHz). ………..…....136
Figure 76. COSY (3) spectrum of compound 4 (CD3OD, 400 MHz). ………..…....137
Figure 77. NOESY (1) spectrum of compound 4 (CD3OD, 400 MHz). ………..….138
Figure 78. NOESY (2) spectrum of compound 4 (CD3OD, 400 MHz). ……….…..139
Figure 79. HMQC (1) spectrum of compound 4 (CD3OD, 400 MHz). ………..…..140
Figure 80. HMQC (2) spectrum of compound 4 (CD3OD, 400 MHz). ………..…..141
Figure 81. HMQC (3) spectrum of compound 4 (CD3OD, 400 MHz). ……………142
Figure 82. HMQC (4) spectrum of compound 4 (CD3OD, 400 MHz). ………..…..143
Figure 83. HMBC (1) spectrum of compound 4 (CD3OD, 400 MHz). ………..…..144
Figure 84. HMBC (2) spectrum of compound 4 (CD3OD, 400 MHz). ……………145
Figure 85. HMBC (3) spectrum of compound 4 (CD3OD, 400 MHz). ………..…..146
Figure 86. HMBC (4) spectrum of compound 4 (CD3OD, 400 MHz). ………..…..147
Figure 87. HMBC (5) spectrum of compound 4 (CD3OD, 400 MHz). ………..…..148
Figure 88. 1H-NMR spectrum of compound 5 (CD3OD, 400 MHz). ………..….....149
Figure 89. 13C-NMR spectrum of compound 5 (CD3OD, 50 MHz). ………..…......150
Figure 90. COSY (1) spectrum of compound 5 (CD3OD, 400 MHz). ………..……151
Figure 91. COSY (2) spectrum of compound 5 (CD3OD, 400 MHz). ………..…....152
Figure 92. NOESY spectrum of compound 5 (CD3OD, 400 MHz). ………..……...153
Figure 93. HMQC spectrum of compound 5 (CD3OD, 400 MHz). ………..……....154
Figure 94. HMBC spectrum of compound 5 (CD3OD, 400 MHz). ………..……....155
Figure 95. 1H-NMR spectrum of compound 6 (CD3OD, 400 MHz). …………..….156
Figure 96. 13C-NMR spectrum of compound 6 (CD3OD, 100 MHz). ………..…....157
Figure 97. COSY (1) spectrum of compound 6 (CD3OD, 400 MHz). ………..……158
Figure 98. COSY (2) spectrum of compound 6 (CD3OD, 400 MHz). ………..……159
Figure 99. NOESY spectrum of compound 6 (CD3OD, 400 MHz). ………..……...160
Figure 100. HMQC spectrum of compound 6 (CD3OD, 400 MHz). ……..……......161
Figure 101. HMBC (1) spectrum of compound 6 (CD3OD, 400 MHz). ……..….....162
Figure 102. HMBC (2) spectrum of compound 6 (CD3OD, 400 MHz). ……..….....163
Figure 103. 1H-NMR spectrum of compound 7 (CD3OD, 400 MHz). ……..……...164
Figure 104. 13C-NMR spectrum of compound 7 (CD3OD, 50 MHz). …..…..….….165
Figure 105. 1H-NMR spectrum of compound 8 (CD3OD, 400 MHz). ……..….…..166
Figure 106. 13C-NMR spectrum of compound 8 (CD3OD, 100 MHz). ……………16
Flavonol Glycosides with alpha-Glucosidase Inhibitory Activities and New Flavone C-Diosides from the Leaves of Machilus konishii
No full textSeventeen flavonoids, five of which are flavone C-diosides, 1 -5, were isolated from the BuOH- and AcOEt-soluble fractions of the leaf extract of Machilus konishii. Among 1 -5, apigenin 6-C-beta-D-xylopyranosyl-2 ''-O-beta-D-glucopyranoside (2), apigenin 8-C-alpha-L-arabinopyranosyl-2 ''-O-beta-D-glucopyranoside (4), and apigenin 8-C-beta-D-xylopyranosyl-2 ''-O-beta-D-glucopyranoside (5) are new. Both 4 and 5 are present as rotamer pairs. The structures of the new compounds were elucidated on the basis of NMR-spectroscopic analyses and MS data. In addition, the H-1- and C-13-NMR data of apigenin 6-C-alpha-L-arabinopyranosyl-2 ''-O-beta-D-glucopyranoside (3) were assigned for the first time. The isolated compounds were assayed against alpha-glucosidase (type IV from Bacillus stearothermophilus). Kaempferol 3-O-(2-beta-D-apiofuranosyl)-alpha-L-rhamnopyranoside (12) was found to possess the best inhibitory activity with an IC50 value of 29.3 mu m
Oligoepicatechins from the Leaves of Machilus konishii
No full textEpicatechin (3) and five oligomers (2, 4, 5, 10, 11) together with five other type compounds were isolated and characterized from n-BuOH and EtOAc soluble fractions of the ethanol extract of the leaves of Machilus konishii Hayata. Their structures were elucidated by means of MS and NMR spectroscopic analyses. Dehydrodiepicatechin A (11) is the first occurrence as a natural product although it has been prepared from epicatechin. The stereochemistry of 11 is elucidated for the first time on the basis of 1D NOESY and chemical model analyses. Tiliroside (7) and kaempferol 3-O--L-(2,4-di-E-p-coumaroyl)-rhamnopyranoside (8) showed moderate inhibitory activity against -glucosidase
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
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Three Adducts of Butenolide and Apigenin Glycoside from the Leaves of Machilus Japonica
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Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
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