The Collaborative International Dictionary of English v.0.48:

Indigrubin \In`dig*ru"bin\, n. [Indigo + L. ruber red.]
   (Physiol. Chem.)
   Same as Urrhodin.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Urrhodin \Ur*rho"din\, n. [1st uro- + Gr. ? a rose.] (Physiol.
   Chem.)
   Indigo red, a product of the decomposition, or oxidation, of
   indican. It is sometimes found in the sediment of
   pathological urines. It is soluble in ether or alcohol,
   giving the solution a beautiful red color. Also called
   indigrubin.
   [1913 Webster]