Cuprate(4-),bis(2-aminoethanol-N,O)[m-[7-(benzoylamino)-3-[[3,3'-dihydroxy-4'-[(1-hydroxy-4,8-disulfo-2-naphthalenyl)azo][1,1'-biphenyl]-4-yl]azo]-4-hydroxy-1,5-naphthalenedisulfonato(8-)]]di-,tetrasodium