Compounds of general formula (Ia), compounds of general formula (Ia’), compounds of general formula (Ib), compounds of general formula (Ib’), compounds of general formula (I), compounds of general formula (I’), and their pharmaceutically acceptable salts, wherein R1, R2, R3, R4, R5, R6, R8, R9, X1, X2, and X3are defined herein, that may be useful as inductors of type I interferon production, specifically as STING active agents, are provided. Also provided are processes for the synthesis and use of compounds of the disclosure.本發明提供可用作I型干擾素產生之誘導劑、具體而言用作STING活性劑之通式(Ia)化合物、通式(Ia’)化合物、通式(Ib)化合物、通式(Ib’)化合物、通式(I)化合物、通式(I’)化合物及其醫藥上可接受之鹽,其中R1、R2、R3、R4、R5、R6、R8、R9、X1、X2及X3定義於本文中。亦提供合成本發明化合物之方法及其用途。