2,2'-Bibenzoic acid 2,2'-Biphenyldicarboxylic acid 2,2'-Dicarboxybiphenyl 2,2'-Diphenic acid 482-05-3 Diphenic acid NSC1966 O,O'-Bibenzoic acid O,O'-Diphenic acid [1,1'-Biphenyl]-2,2'-dicarboxylic acid