You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3aR,5S,7R,7aS)-5-phenoxy-7-(phenylmethoxymethyl)-2-(trichloromethyl)-3a,4,7,7a-tetrahydrooxaphosphinino[4,5-d][1,3]oxazole 5-oxide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H19Cl3NO5P
assistant