You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as (3S)-1-[2-(3-ethyl-4-oxoquinazolin-2-yl)sulfanylacetyl]piperidine-3-carboxamide using the IUPAC nomenclature.
user
C18H22N4O3S
assistant