2416537 BPTC 3,3',4,4'-benzophenone tetracarboxylic acid 3 2416538 BPTC 2-(4-benzoylphenyl)thiazole-4-carboxylic acid 2 2416540 BPTC biphenyl-3,3',5,5'-tetracarboxylic acid 2 2416543 BPTC benign proliferating trichilemmal cyst 1 2416541 BPTC binding potential for impaired radiotracer transfer from plasma to tissue 1 2416542 BPTC binding potential transfer corrected 1 2416539 BPTC biphenyl-3,3',4,4'-tetra-carboxyl-ate 1