Molecular structure of Fast Blue B (CAS NO.14263-94-6) is:

Product Name: Fast Blue B
CAS Registry Number: 14263-94-6
IUPAC Name: Zinc 4-(4-diazonio-3-methoxyphenyl)-2-methoxybenzenediazonium tetrachloride
Molecular Weight: 475.49168 [g/mol]  
Molecular Formula: C₁₄H₁₂Cl₄N₄O₂Zn  
H-Bond Donor: 0  
H-Bond Acceptor: 8
EINECS: 238-153-2
Melting Point: >300 °C(lit.)
Storage temp.: 2-8 °C
Stability: Stable. Incompatible with strong oxidizing agents, alkaline hydroxides. May discolour on exposure to light.
Related Registry Number: 20282-70-6 (Parent)
Canonical SMILES: COC1=C(C=CC(=C1)C2=CC(=C(C=C2)[N+]#N)OC)[N+]#N.[Cl-].[Cl-].[Cl-].[Cl-].[Zn+2]
InChI: InChI=1S/C14H12N4O2.4ClH.Zn/c1-19-13-7-9(3-5-11(13)17-15)10-4-6-12(18-16)14(8-10)20-2;;;;;/h3-8H,1-2H3;4*1H;/q+2;;;;;+2/p-4 
InChIKey: GPPKNJIWDULNQH-UHFFFAOYSA-J

Safty information about Fast Blue B (CAS NO.14263-94-6) is:
Hazard Codes: T
Risk Statements: 45-61-20/21/22 
R45:May cause cancer. 
R61:May cause harm to the unborn child. 
R20/21/22:Harmful by inhalation, in contact with skin and if swallowed.
Safety Statements: 53-45-36/37/39 
S53:Avoid exposure - obtain special instructions before use. 
S45:In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) 
S36/37/39:Wear suitable protective clothing, gloves and eye/face protection.
WGK Germany: 3
F: 8

 Fast Blue B , its cas register number is 14263-94-6. It also can be called 3,3'-Dimethoxybiphenyl-4,4'-di(diazonium) zinc chloride ; (1,1'-Biphenyl)-4,4'-bis(diazonium), 3,3'-dimethoxy-, (T-4)-tetrachlorozincate(2-) (1:1) ; 3,3'-Dimethoxybiphenyl-4,4'-di(diazonium) zinc chloride .It is a green to brown powder.