[0072] Example 1
[0073] Eclipta alba extract compound Wedelia lactone
[0074] (1) Soaking and filtering
[0075] Eclipta prostrata 300kg, completely immersed in 0.75 tons of ethanol (concentration 95%) → soaked overnight (10 hours) → coarse filtration to remove the whole plant residue (retention) → net filtration (suction filtration) or high-speed centrifugation (10000rpm, 10 minutes) to remove dust and fine residue → green clear filtrate.
[0076] (2) Ethanol recovery
[0077] Distillation and recovery of ethanol, the temperature does not exceed 60 ℃ → back distillation for 2 hours each time, remove the extract in the reactor to the collection bucket (the extract is dark green, slightly viscous) → repeat the above steps until all the ethanol is recovered .
[0078] (3) Secondary soaking and back distillation
[0079] Recover 0.75 tons of ethanol, re-soak the whole grass residue → soak overnight, and the requirements for coarse filtration, net filtration and distillation recovery are the same as before. Get the extract.
[0080] (4) Ethyl acetate extraction
[0081] Take the above extract at 50-80°C (more preferably at 60-70°C), heat water and shake and mix, and add hot water 50 times the volume of the extract, and filter with suction to obtain a hot water phase liquid. Add the ethyl acetate for extraction according to the volume ratio of the water phase: the ester phase of 1:1, mix thoroughly and shake, and then stand still until the water phase/ester phase separates. The ethyl acetate layer was removed, vacuum distilled to dryness at 50°C, a small amount of ethanol was added to dissolve, and it was stored in a beaker at 4°C overnight, and a precipitate appeared at the bottom. The precipitate was obtained by suction filtration under reduced pressure, and dried in an oven at 50° C. to obtain a crude product.
[0082] (5) Separation and refining of products
[0083] Take 5g of the crude product, mix the sample on 10g 200-300 mesh silica gel, perform silica gel column chromatography (200g, 200-300 mesh), elution with petroleum ether-acetone gradient, collect once every 100mL, get different polar parts respectively, and combine (TLC petroleum ether-acetone 1:1, Rf=1/3) spots. After concentrating the combined components, the samples were mixed on silica gel for column chromatography, eluted with a dichloromethane-acetone gradient, and collected every 50mL to obtain different polar parts respectively, and combined (TLC dichloromethane-acetone 3: 1. Rf=1/6) spots. After concentrating the combined components, the samples were mixed on silica gel for column chromatography, eluted with a gradient of toluene-acetone-formic acid, and collected every 50 mL to obtain different polar parts respectively, and combined (TLC toluene-acetone-formic acid 10: 10:1, Rf=1/2) spots. After concentrating the combined components, the samples were mixed on silica gel for column chromatography, eluted with a dichloromethane-methanol gradient, and collected every 25mL to obtain different polar parts respectively, and combined (TLC dichloromethane-methanol 20: 1. Rf=1/6) spots. A product with a purity of >90% is obtained, and the yield is about 1%.
[0084] (6) Refined standard products
[0085] Dissolve 30 mg of samples with a purity of >90% in 70% methanol, use a Lichroprep RP-18 (40~63μ) column for reversed phase elution, detect by TLC, collect the 70% eluted samples, and combine them to obtain a purity of >98 % Of standard products. The yield is about 90%. The character, molecular formula, melting point and IR, EIMS, 1 HNMR, 13 The CNMR peaks are assigned as follows:
[0086] Off-white powder, molecular formula: C 16 H 10 O 7 , Mp 315°C (decomposition), UV λmax (MeOH, nm): 211.5 (4.65), 247 (4.40), 304 (4.01) (sh), 350 (4.48). IR(KBr)cm -1 3300, 1715, 1640, 1620, 1445, 1415, 1320, 1205, 1155, 1070. EIMS m/z(%): 314(M + , 100), 313(22), 299([M-CH 3 ], 28), 285(5), 271([M-CH 3-CO], 8), 243([M-CH 3 -CO-CO], 28), 187(17), 69(42). 1 HNMR(δ): 7.23(s), 7.14(s), 6.58(d, J=2.3Hz), 6.42(d, J=2.3Hz), 3.90(s)
[0087] 13 CNMR(δ): 158.0(C-1), 101.1(C-2), 159.6(C-3), 95.6(C-4), 99.3(C-5), 161.1(C-6), 95.0(C -7), 155.5(C-8), 155.0(C-9), 104.7(C-10), 145.2(C-11), 144.3(C-12), 99.0(C-13), 114.0(C- 14), 148.7 (C-15), 55.7 (C-16).
[0088] The results show that the obtained compound is a wedelia lactone of formula II:
[0089]
[0090] The wedelia lactone (hereinafter referred to as APL-1) extracted by the above method was used in the following examples.