You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (4S,8Z)-2-amino-4-thiophen-2-yl-8-(thiophen-2-ylmethylidene)-4,5,6,7-tetrahydrochromene-3-carbonitrile by IUPAC nomenclature, provide its molecular formula.
user
C19H16N2OS2
assistant