Patent ID: 8822678

Claim:
A method for synthesizing a compound of formula I, the method comprising: 1) dissolving 2,2-dimethylol propionic acid and a substituted boric acid of formula IV: in tetrahydrofuran to form a solution; allowing the solution to react at room temperature; adding toluene to the solution, heating, and refluxing the solution; and adding cyclohexane to the solution to yield intermediate II represented by the following formula: wherein in formulae II and IV, R represents an alkyl group having between one and six carbon atoms, or a cycloalkyl group having between one and six carbon atoms; 2) dissolving the intermediate II in a first organic solvent; adding an alkali and 2,4,6-trichlorobenzoyl chloride to the first organic solvent to yield a mixture; allowing the mixture to react in the presence of nitrogen gas at a temperature of between −20 and 40° C. for between 4 and 8 h; adjusting the temperature of the mixture to −10° C.; adding rapamycin and an acid binding agent to the mixture, allowing the mixture to react overnight at room temperature; and separating a product by silica gel column chromatography to yield intermediate III represented by the following formula: wherein, R represents the same structure as that of the intermediate II; and 3) dissolving the intermediate III in a second organic solvent, adding a diol selected from the group consisting of 1,2-, 1,3-, 1,4-, 1,5-diol, and a C 1 -C 6 alkyl substituted diol to the second organic solvent to yield a mixed solution; allowing the mixed solution to react at a temperature of between −20 and 20° C. for between 8 and 14 h; and precipitating and separating a resulting product by using silica gel column chromatography to yield the compound.