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9 Example 9
3.7 g of berberine hydrochloride was added to a 500 ml three-necked flask, 150 ml of ethanol was added,With 3mol / l of sodium hydroxide to adjust the pH to 7-8, heated to 60-70 ° C, stirring dissolved, and thenAdd 4.4 g of oberobic acid, keep the temperature stirring 1-5h, cooling to room temperature, crystallization, too.Filtration, drying, that was Obecaic acid Berberine coupling 6.7g, yield 89%
With dmap; dicyclohexyl-carbodiimide In dichloromethane at 20℃;
6 Example 6: Synthesis of compound 4-1
N-tert-butoxycarbonyl-N '- (2-chlorobenzyloxycarbonyl) -L-ornithine (44 mmol, 15.0 g), N, N'-dicyclohexylcarbodiimide (4.4 Mmol, 0.91 g),4-dimethylaminopyridine (2.2 mmol, 0.3 g) was dissolved with anhydrous dichloromethane (30 ml).Followed by the addition of 6-ethyl deoxycholic acid (26 mmol, 10.93 g) and stirred overnight at room temperature.Filtering to remove the solid insoluble matter, the filtrate evaporated solvent; add ether to the residue,The insoluble impurities in the solution were removed by filtration. The filtrate was concentrated, the ether was used as the developing agent,Collect product fractions. And concentrated under reduced pressure to give the product 8.1 g; Compound 4 Yield 74.1%