Gemcitabine Impurity 10 synthesis

Yield:1147182-15-7 600 mg

Reaction Conditions:

with pyridine in tetrahydrofuran at 20;Inert atmosphere;

Steps:

7 Example 7 Preparation of a Compound 61501c4

At room temperature, under the protection of nitrogen gas, 0.8 g of l3zCl was added to 10 ml of pyridine inwhich 1 g of 61501d had been dissolved, and the temperaNture was kept unchanged until the reaction was complete.The solvent was directly removed from the reaction solution, the residue was dissolved with 50 ml of ethyl acetate,washed with saturated saline and dried over anhydroussodium sulfate. Afier the solvent was removed, 600 mg ofthe compound 61501c4 was obtained via silica gel colunm chromatography (mobile phase: methanol/dichioromethane (the proportion of methanol increased from 2.5% to 10%), gradient elution).

References:

US2018/237466,2018,A1 Location in patent:Paragraph 0131; 0132