You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule [(1S,2R,4S,5S)-9-ethyl-9-methyl-3-oxa-9-azoniatricyclo[3.3.1.02,4]nonan-7-yl] 3-hydroxy-2-phenylpropanoate ?
user
C19H26NO4+
assistant