You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1S,2R,18R,19R,22S,25R,28R,40R)-22-(2-amino-2-oxoethyl)-5,15-dichloro-48-[(2S,3R,4S,5S,6R)-4,5-dihydroxy-3-[(2S,4S,5S,6S)-5-hydroxy-4,6-dimethyl-4-(2-propanoyloxyethylamino)oxan-2-yl]oxy-6-(hydroxymethyl)oxan-2-yl]oxy-19-[[(2R)-2-ethyl-4-methylpentanoyl]amino]-2,18,32,35,37-pentahydroxy-20,23,26,42,44-pentaoxo-7,13-dioxa-24,41,43-triazaoctacyclo[26.14.2.23,6.214,17.18,12.129,33.010,25.034,39]pentaconta-3,5,8(48),9,11,14,16,29(45),30,32,34(39),35,37,46,49-pentadecaene-40-carboxylic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C74H86Cl2N6O26
assistant