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公職◆行政法(包含行政程序法等)題庫

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下列九個類黃酮化合物(19)係分離自菲律賓楠(Machilus philippinensis),其分離方法/步驟如下: The EtOH extract (160 g) of the dried leaves of M. philippinensis (774 g) was partitioned into fractions soluble in CH2Cl2 (38.30 g), EtOAc (10.51 g), n-BuOH (31.02 g) and H2O (74.12 g) by a liquid-liquid partitioning process. Part of the EtOAc-soluble fraction (6.03 g out of 10.51 g) was fractionated on a Sephadex LH-20 column (815 × 35 mm, MeOH) to give six fractions (E1~6). An aliquot of fraction E2 (45.0 mg out of 500.7 mg) was separated by a semi-preparative RP-18 HPLC column (Phenomenex® Prodigy ODS-3, 250 × 10 mm, 5 μm), each run 5.0 mg, delivered by 16% MeCN in H2O for 30 min, to 25% MeCN in 40 min by a linear gradient mode, and then MeCN for 15 min, with a flow rate of 2.5 mL/min and detection at 300 nm. After nine runs, the fractions containing pure compounds were evaporated under reduced pressure to give 3 (2.9 mg, tR = 21.39 min), 4 (10.0 mg, tR = 22.61 min), 6 (7.3 mg, tR = 30.86 min), 7 (4.8 mg, tR = 36.36 min), and 9 (1.9 mg, tR = 42.33 min), respectively. An aliquot of fraction E3 (273.8 mg out of 1.20 g) was separated on a Lobar (low-pressure) RP-18 column (LiChroprep RP-18, size B, 310 × 25 mm; 40-63 μm, Merck), delivered by a stepwise gradient of MeOH―H2O from 30:70 to 100:0, to give six subfractions (E3-1~6). Fractions E3-3 (24.7 mg) and -5 (2.0 mg) were pure 5 and 8, respectively. An aliquot of fraction E6 (201.0 mg out of 756.0 mg) was separated on the same Lobar RP-18 column, delivered by a stepwise gradient of MeOH―H2O from 35:65 to 85:15, to give five subfractions (E6-1~5). Fractions E6-2 (14.4 mg) and -4 (2.3 mg) were pure 1 and 2, respectively.


(一) 以上圖右之方式表達化合物1至9之分離流程。(10分)

(二) 試由分離之結果簡述所使用的層析法之分離原理與特性。(16分)

#1197
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