The Pigment Red 52:1, with the CAS registry number 52202-90-1, is also known as 2-Naphthalenecarboxylic acid, 4-((4-chloro-5-methyl-2-sulfophenyl)azo)-3-hydroxy-, calcium salt (2:1). Its EINECS number is 257-731-5. This chemical's molecular formula is 2(C₁₈H₁₂ClN₂O₆S).Ca and formula weight is 879.71. What's more, both its IUPAC name and systematic name are the same which is called Calcium (4E)-4-[(4-chloro-5-methyl-2-sulfophenyl)hydrazinylidene]-3-oxonaphthalene-2-carboxylate.

Physical properties about this chemical are: (1)#H bond acceptors: 16; (2)#H bond donors: 6; (3)#Freely Rotating Bonds: 10; (4)Polar Surface Area: 301.32 Å².

You can still convert the following datas into molecular structure:
(1)SMILES: [H+].[H+].[Ca+2].Cc3cc(N=Nc1c2ccccc2cc(C([O-])=O)c1O)c(cc3Cl)S([O-])(=O)=O.[O-]C(=O)c3cc1ccccc1c(N=Nc2cc(C)c(Cl)cc2S([O-])(=O)=O)c3O
(2)InChI: InChI=1/2C18H13ClN2O6S.Ca/c2*1-9-6-14(15(8-13(9)19)28(25,26)27)20-21-16-11-5-3-2-4-10(11)7-12(17(16)22)18(23)24;/h2*2-8,22H,1H3,(H,23,24)(H,25,26,27);/q;;+2/p-2
(3)InChIKey: MGPKPANYASGNOR-NUQVWONBAY