The invention relates to a compound of formula (I)
wherein A1 to A3 and R1 to R3 are defined as in the description and in the claims. The compound of formula (I) can be used as a medicament.
本发明涉及一种化合物,其
化学式为(I),其中A1到A3和R1到R3的定义如说明书和权利要求书中所述。化合物(I)可用作药物。