4,4'-Bibenzoic acid 4,4'-Biphenyldicarboxylic acid 4,4'-Dicarboxybiphenyl 4,4'-Diphenic acid 787-70-2 NSC60016 Usaf do-69 WLN: QVR DR DVQ [1,1'-Biphenyl]-4,4'-dicarboxylic acid p,p'-Diphenic acid