You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by methyl 2-[(3S)-4-(cyclopropylmethyl)-5-oxo-3-propan-2-yl-1,4-diazepan-1-yl]pyridine-3-carboxylate ?
user
C19H27N3O3
assistant