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ChemicalBook CAS DataBase List ELEUTHEROSIDE A
474-58-8

ELEUTHEROSIDE A synthesis

11synthesis methods
-

Yield:474-58-8 82%

Reaction Conditions:

with trimethylsilyl trifluoromethanesulfonate in ethylbenzene at 85; for 15 h;

Steps:

9 Synthesis of daucosterol

β-sitosterol124.4g0.3mol),D-glucose (18.0 g, 0.1 mol) dissolved in ethylbenzene (600 mL).At 80°C,TMSOTf (8.9 g/7.3 mL, 40 mmol)was added and underprotection carried out constant temperature reaction until the TLC detected almost complete disappearance of D-glucose (about 15h). After the reaction was concentrated , it wassubjected to silica gel column chromatography (silica gel 100-200 mesh) using dichlromethaneas eluent. TLC assay until the eluent is free of β-sitosterol, the eluent was concentrated to give β-sitosterol(83.0g, 0.2mol), continue the elution with ethyl acetateas eluent, and TLC assay until there is no title compoundin the eluent. The eluent was concentrated to give the title compound (47.3 g) in 82% yield and HPLC purity 97.8%.

References:

CN104693266,2018,B Location in patent:Paragraph 0062-0064

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