Aminoketone compound, and preparation method therefor and use thereof

A compound of formula (I), or a tautomer, an enantiomer, a diastereoisomer, a racemate, or a mixture thereof, or a pharmaceutically acceptable salt thereof,

• wherein,
• R1 is selected from the group consisting of deuterium and C1-C6 alkyl;
• R2, R3 and R4 are each independently selected from the group consisting of hydrogen, C1-C6 alkyl, deuterated C1-C6 alkyl and —(C═O)—C1-C6 alkyl;
• R5, R6, R7, R8 and R9 are each independently selected from the group consisting of hydrogen, C1-C6 alkyl, halogenated C1-C6 alkyl, C1-C6 alkoxy, halogenated C1-C6 alkoxy, halogen, nitro and cyano;
• and at least 2 of R5, R6, R7, R8 and R9 are hydrogen;
• the stereo configuration of the α-position or β-position carbon atom is each independently selected from the group consisting of:
• R, S and (R, S).