4315-43-9 HR 2154 NSC 57143 NSC57143 Urea, 1,1'-p-phenylenebis[3-(m-2-imidazolin-2-ylphenyl)-, dihydrochloride Urea, N,N''-1,4-phenylenebis[N'-[3-(4,5-dihydro-1H-imidazol-2-yl)phenyl]-, dihydrochloride