Example 1
 Eclipta alba extract compound Wedelia lactone
 (1) Soaking and filtering
 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.
 (2) Ethanol recovery
 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 .
 (3) Secondary soaking and back distillation
 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.
 (4) Ethyl acetate extraction
 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.
 (5) Separation and refining of products
 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%.
 (6) Refined standard products
 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:
 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)
 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).
 The results show that the obtained compound is a wedelia lactone of formula II:
 The wedelia lactone (hereinafter referred to as APL-1) extracted by the above method was used in the following examples.