You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
calcium;(4S,4aR,5S,6S,12aR)-2-carbamoyl-4-(dimethylamino)-5,6,10,12a-tetrahydroxy-6-methyl-3,12-dioxo-4,4a,5,5a-tetrahydrotetracene-1,11-diolate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H22CaN2O9
assistant