Cap-dependent endonuclease inhibitors

Provided is a compound of Formula (I) below, or a pharmaceutically acceptable salt, metabolite, or prodrug thereof: wherein: A1 is CR4 or N; A2 is CR5R6 or NR7; A3 is CR5'R6' or NR7'; each of R1, R2, R2', R3, R3', R4, R5, R5', R6, R6', R7, and R7', independently, is hydrogen, deuterium, halogen, cyano, hydroxyl, carboxyl, amino, formyl, nitro, C1-6 alkyl, C2-6 alkenyl, C2-6 alkynyl, C1-6 alkoxy, C2-6 alkenyloxy, C1-6 alkylcarbonyl, C1-6 alkyloxycarbonyl, C1-6 alkylamine, C3-20 carbocyclyl, or C3-20 heterocyclyl; or R5 and R6, R5' and R6', or R5 and R5', together with the adjacent atom to which they are each attached, form C3-10 carbocyclyl or C3-10 heterocyclyl. Further provided are a method of using the above-described compound, or the pharmaceutically acceptable salt, metabolite, or prodrug thereof for treating influenza and a pharmaceutical composition containing same.