Those molecules are the exact same molecules as here on Earth, but we now want to see them under very different conditions, very high temperatures and pressures. (discovermagazine.com)
If there existed only more or less random occasions, we could not speak of a molecule at all, but, in fact, we are able to identify a single molecule through a long period of time as the same molecule. (religion-online.org)
If we make antibiotics in a pharmaceutical vat, do they somehow lose their value compared to the kind made «naturally» by fungus, even if we're getting the same molecule in the end? (mommyish.com)