You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (12R,15R,18S)-12,18-dimethyl-15-(2-methylpropyl)-21-phenyl-8-[3-(tetrazol-1-yl)propanoyl]-1,4,8,11,14,17,20,22-octazabicyclo[17.3.0]docosa-19,21-diene-3,10,13,16-tetrone by IUPAC nomenclature, provide its molecular formula.
user
C30H42N12O5
assistant