| 摘要: | 桑葉為桑科Moraceae植物桑Morus alba L.之乾燥葉，在「臺灣中藥典」記載為辛涼解表藥，芸香苷是桑葉的指標成分。最近文獻報導，摩查爾酮B是由桑葉中分離與確認出來的新天然化合物，屬於查爾酮衍生物，摩查爾酮B具有中等的抗癌活性(人類結腸及胃癌)，根據文獻報導，天然或合成的查爾酮與類似物顯示具有不同的生物活性如抗氧化、抗菌、抗發炎、抗癌等，因此被關注可以開發成為治療用藥的可能，由於摩查爾酮B分離的量很少，且這個天然物到目前為止並未有合成之報導，為了進一步探討其生物活性，在本論文中，針對摩查爾酮B 及類似物進行有效的合成方法探討。
在本論文中描述一個有效的合成方法進行查爾酮B及類似物的合成，Rap−Stoermer縮合反應及1,3-prenyl group重排是主要的合成方法，從2,4-dihydroxyacetophenone與2,4-dihydroxybenzaldehde為起始物開始，經6個合成步驟成功的合成了Mora-41-2 (摩查爾酮B的類似物)，然而，最後一步驟去甲基反應沒有成功合成出摩查爾酮B，所有合成的化合物皆由光譜分析確認其結構。
Mulberry leaf is the dry leaf of Morus alba L. (Fam. Moraceae) used as pungent-cold exterior-releasing medicinal described in the Taiwan Herbal Pharmacopeia. Rutin is the marker compound of mulberry leaf. Recently, morachalcone B was isolated and characterized as a new chalcone derivative from mulberry leaf and displayed moderate cytotoxic activity against HCT-8 (human colon cancer) and BGC823 (human stomach cancer) human cancer cell lines. Naturally occurring chalcones and synthesized analogues have been reported to have various bioactivities, such as antioxidative, antibacterial, anti-inflammatory, and anticancer activities. Due to the variety of their beneficial effects, compounds related to chalcones have attracted attention as a novel potential therapeutic target. Until now, the total synthesis of morachalcone B was not reported yet. In order to obtain more material for further study the biological activities, in this thesis, the synthesis of Morachalcone B and analogues was investigated.
In this thesis, an efficient method to synthesize morachalcone B and analogues was described. Rap−Stoermer condensation and 1,3-prenyl rearrangement were used as two key synthetic methods. Starting from 2’,4’-dihydroxyacetophenone and 2,4-dihydroxybenzaldehde, Mora-41-2 (morachalcone B analogue) was successfully synthesized in six steps. However, demethylation of Mora-41-2 with excess BBr3 was not successful. The structures of synthesized compounds were confirmed on the basis of spectroscopic analysis. |
