Complex sentence: Oxytocin has a molecular mass of 1007 Da, and one international unit (IU) of oxytocin is the equivalent of about 2 μg of pure peptide.
Split into simpler sentences: Oxytocin has a molecular mass of 1007 daltons. One international unit (IU) of oxytocin is the equivalent of about 2 micrograms of pure peptide.