Composition of aminopyran derivative

A pharmaceutical formulation comprising auxiliary materials and an active ingredient, the auxiliary materials comprising a neutral diluent, and the active ingredient being a compound of general formula (A) and its stereoisomer, or, a pharmaceutically acceptable salt or prodrug thereof

• R1 is each independently selected from H, F, Cl, Br or I;
• R2 is each independently selected from H, F, Cl, Br, I or C1-4 alkyl, wherein the alkyl is optionally further substituted by 0-4 substituents selected from H, F, Cl, Br or I;
• ring D is selected from a 5-membered heteroaryl ring group, wherein the heteroaryl ring group is optionally further substituted by 0-4 substituents selected from H, C1-4 alkyl, S(═O)2—C1-4 alkyl or D1, and the heteroaryl ring group contains 2 or 3 N atoms;
• D1 is each independently selected from a 5-membered heteroaryl ring group, wherein the heteroaryl ring group is optionally further substituted by 0-4 substituents selected from H or C1-4 alkyl, and the heteroaryl ring group contains 2, 3 or 4 N atoms;
• and
• n is selected from 0, 1, 2, 3, 4 or 5.