Oxalan :: Oxalan (n.) A complex nitrogenous substance C3N3H5O3 obtained from alloxan (or when urea is fused with ethyl oxamate), as a stable white crystalline powder; -- called also oxaluramide..
Oxalantin :: Oxalantin (n.) A white crystalline nitrogenous substance (C6H4N4O5) obtained by the reduction of parabanic acid; -- called also leucoturic acid.