The present invention relates to a process for preparing a Parp1/2 inhibitor, i.e., (R)-2-fluoro-10a-methyl-7,8,9,10,10a,11-hexahydro-5,6,7a,11-tetraazacyclohepta[def]cyclopenta[a]fluoren-4(5H)-one (hereinafter referred to as Compound A), crystalline forms (polymorphs) of Compound A or hydrate or solvate thereof, especially crystalline form C of Compound A sesqui-hydrate, methods for preparing the crystalline forms, and the use thereof.本發明涉及製備Parp1/2抑制劑,即(R)-2-氟-10a-甲基-7,8,9,10,10a,11-六氫-5,6,7a,11-四氮雜環庚並[def]環戊並[a]芴-4(5H)-酮(在下文中稱爲化合物A)的方法,化合物A或其水合物或溶劑化物的結晶形式(多晶型物),尤其是化合物A倍半水合物的結晶形式C,製備所述結晶形式的方法及其用途。無
