The invention provides a synthetic method of
empagliflozin. The synthetic method comprises the following steps of: by using 2, 3, 4, 6-
tetra-O-benzyl-D-glucopyranose acid-1,5-
lactone and p-chloroiodobenzene as raw materials, performing a reaction so as to obtain an intermediate as shown in a formula II; performing reduction to eliminate a hydroxyl on anomeric carbon of the intermediate as shown in the formula II, so as to obtain an intermediate as shown in a formula III; by using (S)-3-phenoxy
tetrahydrofuran, the intermediate as shown in the formula III, and paraform as raw materials, performing a reaction so as to obtain an intermediate as shown in a formula IV; and removing benzyl of the intermediate as shown in the formula IV, so as to obtain the
empagliflozin. According to the synthetic method disclosed by the invention, firstly 1-p-chlorophenyl-2,3,4,6-
tetra-O-benzyl-D-glucopyranose is prepared, then the intermediate of the 1-p-chlorophenyl-2,3,4,6-
tetra-O-benzyl-D-glucopyranose, the (S)-3-phenoxy
tetrahydrofuran and the paraform are used as the raw materials, the
empagliflozin protected by intermediate benzyl is prepared, and finally a benzyl
protecting group is removed, so that the empagliflozin is obtained. The synthetic
route of the synthetic method disclosed by the invention is short, and the total yield is high.