• CAS:58816-01-6

  P-4-pyridinyl-Phosphonic acid

• CAS:67892-43-7

  3-sulphophthalic acid

• CAS:1537175-69-1

  2-(Diphenylphosphino)terephthalic acid

• CAS:223519-93-5

  1,​4-​Benzenedicarboxylic acid, 2,​5-​diphosphono-

• CAS:

  2,5-Diethynyl terephthalic acid