I. 台灣青脆枝抗癌成分分離及定性定量分析 II. 小葉紫檀活性成分及其立體衍生物合成研究

I.Isolation, Qualitative and Quantitative Analysis of Anti-cancer Components from Formosan Nothapodytes foetida II. Bioactive Components of Pterocarpus santalinus and Synthetic Investigation of their Stereochemical Derivatives

吳守方(Shou-Fang Wu)

指導教授 ： 吳永昌

高雄醫學大學/藥學院/天然藥物研究所碩士班/博士(2013年)

摘要

本研究為進行兩株植物青脆枝及小葉紫檀之天然物化學及其生物活性研究。青脆枝(Nothapodyte foetida)為茶茱萸科(Icacinaceae)鷹紫花樹屬(Nothapodytes)植物。將台灣本土栽種之青脆枝未成熟種子以甲醇萃取，並以活性導引分離法進行活性成分分離，得到出11個化合物，其中包含六個camptothecinoids： 9-methoxy-18,19-dehydro- camptothecin (NFS1)、 5-hydroxymappicine-20-O-??-glucopyranoside (NFS2a/2b) 、camptothecin (NFS3)、9-methoxy-camptothecin (NFS4)、5-hydroxycamptothecin (NFS5a/5b) 及5-dydroxy-9-methoxy-camptothecin (NFS6a/6b)；3個flavonoids：diosmetin (NFS7)，apigenin (NFS8)及apigenin-O-glucopyranoside (NFS9)；1個phenol：rosin (NFS10)及amarantholidoside IV (NFS11)。其中NFS1及NFS2a/2b為新化合物，且NFS1對六種人類癌細胞株(HepG2、Hep3B、MDA-MB-231、MCF-7、A549及Ca9-22)具有明顯細胞毒殺活性(IC50：0.24-6.57 ?嵱)。同時針對台灣產青脆枝各部位(未成熟/成熟種子、葉子、枝幹及根部)利用HPLC進行活性成分之定性、定量指紋圖譜分析，發現campthothecin及9-methoxy-camptothecin於根部具有最高含量。小葉紫檀(Pterocarpus santalinus)為豆科(Leguminosae)紫檀屬(Pterocarpus)植物，為印度特有之紫檀屬植物。小葉紫檀心材部位以甲醇進行萃取，並以二氯甲烷及50%甲醇水溶液進行分配萃取，初部活性篩選發現二氯甲烷層具有較佳之細胞毒殺(IC50 < 20 ?慊/mL)及抗發炎之活性(IC50 < 10 ?慊/mL)，利用活性導引分離法尋找活性成分，共自本植物萃取物中分離出23個化合物，包含五個新benzofurans (pterolinus A-E, PS1-5)、七個新neoflavonoids (pterolinus F-I, PS8-12, pterolinus M, PS13及pterolinus J, PS17)、一個新phenanthrenequinone (pterolinus K, PS20)、一個新chalcone (pterolinus L, PS21)及九個已知化合物，經光譜解析及文獻資料比對分別為5-benzofuranol (PS6)、melanoxin (PS7)、S-3′-hydroxy-4-4′- dimethoxydalbergione (PS14) 、methanpne (PS15) 、cearoin (PS16)、 melannein (PS18)、 dalbergin (PS19)、benzoic acid (PS22) 及 2-propenal (PS23)。其中PS15針對Ca9-22細胞株具有最顯著的毒殺效果，其IC50為0.46 ?慊/mL。此外，部分的neoflavonoids 及 benzofurans結構對超氧自由基及elasetase 釋放皆具有抑制效果，其中以PS2具有最佳超氧自由基抑制效果，其IC50為0.19 ?慊/mL。除青脆枝及小葉紫檀天然物成分研究外，更進一步確認pterolinus E (PS5) 之絕對立體，經由光譜資料及Evans非對稱化學合成方法將pterolinus E (PS5)中的立體中心定義為S、S，並且評估PS4、PS5及其衍生物細胞毒殺活性，發現PS4及PS5中para-quinone 及epoxide 為其影響活性之關鍵基團。

關鍵字

青脆枝 ； 喜樹鹼 ； 定性定量分析 ； 小葉紫檀 ； Evans非對稱合成

並列摘要

The study focuses on natural product chemistry and their bioactivity of two plants Nothapodyte foetida and Pterocarpus santalinus. N. foetida belongs to Icacinaceae family and Nothapodytes genus. The MeOH extract of unripe seeds from Taiwanese N. foetida was purfied according to the active-guided fractionation. Among them, two new compounds 9-methoxy-18,19-dehydroxycamptothecin (NFS1) and 5-hydroxy-mappicine-20-O-??-glucopyranoside (NFS2a/2b) were obtained with nine known compounds, including camptothecin (NFS3), 9-methoxy-camptothecin (NFS4), 5-hydroxycamptothecin (NFS5a/5b), 5-dydroxy-9-methoxycamptothecin (NFS6a/6b), diosmetin (NFS7), apigenin (NFS8), apigenin-O-glucopyranoside (NFS9), rosin (NFS10) and amarantholidoside IV (NFS11). NFS1 showed significant cytotoxicity against the cancer cell lines HepG2, Hep3B, MDA-MB-231, MCF-7, A549, and Ca9-22 with IC50 values ranged from 0.24 to 6.57 ?嵱. Furthermore, HPLC profiles were built for the qualitative and quantitative analysis of these active constituents in ripe and unripe seeds, leaves, stems and roots of N. foetida. The results revealed that NFS3 and NFS4 have the highest concentrations found in the roots part of the plant. P. santalinus belongs to Legume family and Pterocarpus genus, which is an endemic plant in southern India. The MeOH extract of heartwood was portioned between CH2Cl2 and 50% MeOH (aq.), and the CH2Cl2 layer showed potent cytotoxicity (IC50 < 20 ?慊/mL) and anti-inflammatory activity (IC50 < 10 ?慊/mL). Twenty three compounds were isolated by active-guided fractionation, included five new benzofurans (pterolinus A-E, PS1-5), seven new neoflavonoids (pterolinus F-I, PS8-12, pterolinus M, PS13 and pterolinus J, PS17), one new phenanthrenequinone (PS20), one new chalcone (PS21) along with nine known compounds 5-benzofuranol (PS6), melanoxin (PS7), S-3′-hydroxy-4-4′-dimethoxydalbergione (PS14), methanpne (PS15), cearoin (PS16), melannein (PS18), dalbergin (PS19), benzoic acid (PS22) and 2-propenal (PS23). The structures of above compounds PS1-23 were elucidated by spectroscopy methods and literatures data. Among them, PS15 showed signigicant cytotoxicity against tumor cells Ca9-22 with an IC50 value of 0.46 ?慊/mL. Besides, most neoflavonoids and benzofurans showed potent inhibition of superoxide and elastase relaease, of thses compounds, PS2 showed a selective effect against superoxide anion generation with an IC50 value of 0.19 ?慊/mL. Besides natural products research of these two plants, the absolute configuration of pterolinus E (PS5) was further comfirmed by Evans asymmetric synthetic methods and optical data. The chiral centers of pterolinus E (PS5) were identified as S, S, and the para-quinone and epoxide moieties of pterolinus D (PS4) and pterolinus E (PS5) were the key functional groups according to the cytotoxicity evaluation.

並列關鍵字

Nothapodyte foetida ； camptothecin ； qualitative and quantitative analysis ； Pterocarpus santalinus ； Evans asymmetric synthesis

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