(R)-N-((5-(2-(2-amino-1,4,5,6,7,8-hexahydro-4-oxopyrido(2,3-d)pyrimidin-6-yl)ethyl)-2-thienyl)carbonyl)-L-glutamatic acid disodium salt
(r)-n-((5-(2-(2-amino-1,4,5,6,7,8-hexahydro-4-oxopyrido(2,3-d)pyrimidin-6-yl)ethyl)-2-thienyl)carbonyl)-l-glutamatic acid disodium salt