Mepixanox has a chemical formula of C20H21NO3 and a molar mass (mass of a sample of that compound divided by the amount of substance in that sample) of 323.392 gmol.
C20H21NO3 323.392 gmol In chemistry, the molar mass of a chemical compound is defined as the mass of a sample of that compound divided by the amount of substance in that sample, measured in moles. 
