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Title: | 第一部分 小葉樟之葉部成分研究 第二部份 苦藤莖部成分及borapetoside C衍生物製備之研究 Part Ⅰ. Chemical investigation of the leaves of Cinnamomum validinerve Part Ⅱ. Chemical investigation of Tinospora crispa stems and preparation of borapetoside C derivatives |
Authors: | Tai-Lin Yao 姚代琳 |
Advisor: | 李水盛 |
Keyword: | 小葉樟,粗脈桂,樟科,甲型葡萄糖?抑制劑,黃酮類,苦藤,波葉青牛膽,borapetoside C,化學結構修飾, Cinnamomum validinerve,Lauraceae,α-Glucosidase inhibitors,flavonoid,Tinospora crispa,borapetoside C,chemical modification, |
Publication Year : | 2015 |
Degree: | 碩士 |
Abstract: | 第一部分 小葉樟之葉部成份研究 小葉樟(Cinnamomum validinerve)為樟科(Lauraceae)植物,分佈於香港、廣東、廣西及台灣,過去文獻報導甲型葡萄糖酶抑制劑,可幫助對第二型糖尿病的患者控制血糖。因此利用甲型葡萄糖酶之抑制活性為導向針對小葉樟葉部之乙醇萃取物進行分離。其中19個化合物中有15個為黃酮醇醣苷(2-16),並用少量的成分,應用高效且有效的HPLC-DAD-SPE-NMR和HPLC-MS技術進行分析。此植物的成分大多為黃酮醇醣苷,和菲律賓楠(Machilus philippinensis)相似,可做為樟科植物化學分類的探討。 第二部分 苦藤莖部成分及borapetoside C衍生物製備之研究 苦藤莖部作為民間藥解熱鎮痛之藥用植物,一些研究報導其具有抗發炎和免疫調節活性,最近我們實驗室經由合作發現borapetoside C具有降血糖活性,因此,本研究針對其結構進行化學修飾之探討。藉由Sephadex LH-20管柱及低壓逆相層析管柱分離苦藤莖部之乙醇萃取物,在正丁醇可溶部分中得到6個化合物(20-25),其中化合物Succinic acid (2(S)-hydroxy-1(S)-methyl)propyl ester (23)及6'-O-lactoyl-borapetoside E (25)為新天然物。接著將分離得到大量之borapetoside C (21)溶於正丁醇中,再加入鈉金屬於氧氣下反應,得到五個產物,包含兩個glucosides及三個aglycons。結構解析這些產物,發現在強鹼反應下,C-18酯基被水解,甚至更進一步還原成一級醇,此外,C-3雙鍵系統被還原或是異構化,然而C-6上的糖基沒有完全得被切除,因此尚須更長的時間進行反應。由實驗結果得知,利用此方法可有效針對雙萜類結構之化合物進行結構修飾。 Part 1. Chemical investigation of Cinnamomum validinerve leaf Cinnamomum validinerve is a Lauraceae plant, growing in Hong Kong, Guangdong, Guangxi and Taiwan. α-Glucosidase inhibitors could assist the control of the postprandial blood glucose level for the type-II diabetes patients. Following bioassay-guided fractionation and separation against α-Glucosidase, 19 known compounds in total from the EtOH extract of C. brevipedunculatum leaves were identified. Among them, 15 flavonol glycosides (2-16) were characterized by application of HPLC-DAD-SPE-NMR and HPLC-MS hyphenations, which require only small amount of plant materials and are efficient and powerful in phytochemical analysis. These flavonoid glycosides are similar to those from Machilus philippinensis, indicating potential chemotaxonomic significance for the Lauraceae family. Part 2. Chemical investigation of Tinospora crispa stem and preparation of borapetoside C derivatives The stems of Tinospora crispa has has been used as folklore medicine for antipyretic and analgesia. Some studies have shown its anti-inflammatory and immunomodulatory activities. Our lab via cooperation recently discovered the hypoglycemic activity of borapetoside C. Hence, this study was aimed to isolate this comstituent for further chemical modification. Six compounds (20-25) were isolated from the n-BuOH soluble fraction of the EtOH extract of the stems of T. crispa via Sephadex LH-20 and reversed phase Lobar column. Of these, succinic acid (2(S)-hydroxy-1(S)-methyl)propyl ester (23) and 6'-O-lactoyl-borapetoside E (25) are new natural products. Preparation of borapetoside C derivarives was undertaken by reacting with sodium in n-BuOH under oxygen. Five products including two glucosides and three aglycons were characterized. Structural analysis of these products indicates that several reactions took place. Hydrolysis of C-18 ester is the common phemomenon under such strong alkaline condition and this functional group could be futher reduced to primary alcohol. The C-3 double bond was either reduced or isomerized. The 6-O-glucosyl group, however, was not removed completely. To achieve the last purpose, longer reaction time might be required. This approach is effective to prepare some borapetoside C derivatives. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/54044 |
Fulltext Rights: | 有償授權 |
Appears in Collections: | 藥學系 |
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