You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-(2-aminoethyldisulfanyl)ethyl]-N'-[2-[2-[[4-[2-(2-aminoethyldisulfanyl)ethylamino]-4-oxobutanoyl]amino]ethyldisulfanyl]ethyl]butanediamide;dihydrochloride is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H42Cl2N6O4S6
assistant