Benzoic acid, 5-[[4-[(7-amino-1-hydroxy-3-sulfo-2-naphthalenyl)azo]-1-naphthalenyl]azo]-2-hydroxy-, disodium salt

直接黑51

Also known as: C.I. Direct Black 51, Ci 27720, Saturn black B, EINECS 222-351-0, disodium 5-[[4-[(7-amino-1-hydroxy-3-sulphonato-2-naphthyl)azo]-1-naphthyl]azo]salicylate, Benzoic acid, 5-[[4-[(7-amino-1-hydroxy-3-sodiosulfo-2-naphthalenyl)azo]-1-naphthalenyl]azo]-2-hydroxybenzoic acid sodium salt, disodium,(3E)-3-[[4-[(2E)-2-(7-amino-1-oxo-3-sulfonatonaphthalen-2-ylidene)hydrazinyl]naphthalen-1-yl]hydrazinylidene]-6-oxocyclohexa-1,4-diene-1-carboxylate

Benzoic acid, 5-[[4-[(7-amino-1-hydroxy-3-sulfo-2-naphthalenyl)azo]-1-naphthalenyl]azo]-2-hydroxy-, disodium salt (CAS 3442-21-5) is a compound in the Organic Compounds category listed in the Jingsj chemical database. It has the molecular formula C27H17N5Na2O7S and a molecular weight of 601.49800 g/mol. It is also known as C.I. Direct Black 51, Ci 27720 and Saturn black B. No supplier offers are currently listed; request a quote. Record last updated Aug 21, 2026.

CAS No.

3442-21-5

Jingsj CID

J-1095669-6

Molecular Formula

C₂₇H₁₇N₅Na₂O₇S

Chinese Name

直接黑51

Molecular Weight

601.49800 g/mol

Category

Organic Compounds

Last updated

8/21/2026