for sensitive chromatographic and analytical workflows requiring minimal baseline interference.
Room temperature Ships Normal Check lot-specific COA for exact specifications.
SDS, COA, datasheet, and spec sheet available for download. Lot-specific COA accessible via lot number lookup.
Cited in 1 peer-reviewed publications across chromatography, organic synthesis, and cross-coupling reactions.
Fast Black K salt is a water soluble dye used for the histochemical demonstration of acid phosphatases with naphthol AS phosphates. Also useful for staining of proteinaceous tissue components.
A water soluble dye
| Pubchem Sid | 488199338 |
|---|---|
| Pubchem Sid Url | https://pubchem.ncbi.nlm.nih.gov/substance/488199338 |
| Canonical Smiles | COC1=CC(=C(C=C1N=NC2=CC=C(C=C2)[N+](=O)[O-])OC)[N+]#N.COC1=CC(=C(C=C1N=NC2=CC=C(C=C2)[N+](=O)[O-])OC)[N+]#N.[Cl-].[Cl-].Cl[Zn]Cl |
| IUPAC Name | dichlorozinc;2,5-dimethoxy-4-[(4-nitrophenyl)diazenyl]benzenediazonium;dichloride |
| InChIKey | NZWZSUSPTZUGNN-UHFFFAOYSA-J |
| INCHI | 1S/2C14H12N5O4.4ClH.Zn/c2*1-22-13-8-12(14(23-2)7-11(13)16-15)18-17-9-3-5-10(6-4-9)19(20)21;;;;;/h2*3-8H,1-2H3;4*1H;/q2*+1;;;;;+2/p-4 |
| Isomeric SMILES | COC1=CC(=C(C=C1N=NC2=CC=C(C=C2)[N+](=O)[O-])OC)[N+]#N.COC1=CC(=C(C=C1N=NC2=CC=C(C=C2)[N+](=O)[O-])OC)[N+]#N.[Cl-].[Cl-].Cl[Zn]Cl |
| Alternate CAS | 27766-47-8 |
| Molecular Weight | 417.88 |
Comprehensive hazard, handling, storage, and regulatory compliance document.
Download SDS →Lot-specific quality data. Enter your lot number to retrieve the exact COA.
Look up COA →Full quality attributes and acceptance criteria for this grade.
View spec sheet →Taxonomy Tree
| Kingdom | Organic compounds |
|---|---|
| Superclass | Organoheterocyclic compounds |
| Class | Azobenzenes |
| Subclass | Not available |
| Intermediate Tree Nodes | Not available |
| Direct Parent | Azobenzenes |
| Alternative Parents | Dimethoxybenzenes Nitrobenzenes Methoxyanilines Phenoxy compounds Anisoles Nitroaromatic compounds Alkyl aryl ethers Organic diazonium salts Azo compounds Propargyl-type 1,3-dipolar organic compounds Organic transition metal salts Organic oxoazanium compounds Organic metal halides Organic oxides Hydrocarbon derivatives Organic chloride salts Organic cations |
| Molecular Framework | Not available |
| Substituents | Azobenzene - P-dimethoxybenzene - Dimethoxybenzene - Nitrobenzene - Methoxyaniline - Phenoxy compound - Nitroaromatic compound - Anisole - Phenol ether - Methoxybenzene - Alkyl aryl ether - Monocyclic benzene moiety - Benzenoid - Azo compound - C-nitro compound - Organic diazonium salt - Organic nitro compound - Allyl-type 1,3-dipolar organic compound - Organic transition metal salt - Organic 1,3-dipolar compound - Propargyl-type 1,3-dipolar organic compound - Organic metal halide - Ether - Organic oxoazanium - Organic chloride salt - Organic salt - Organonitrogen compound - Organic oxide - Organic oxygen compound - Organooxygen compound - Hydrocarbon derivative - Organic nitrogen compound - Organic cation - Aromatic homomonocyclic compound |
| Description | This compound belongs to the class of organic compounds known as azobenzenes. These are organonitrogen aromatic compounds that contain a central azo group, where each nitrogen atom is conjugated to a benzene ring. |
| External Descriptors | Not available |
Find and download the COA for your product by matching the lot number on the packaging.
| Lot Number | Certificate Type | Date | Item |
|---|---|---|---|
 L2523379 | Certificate of Analysis | Dec 03, 2025 | F113033 |
| L2523390 | Certificate of Analysis | Dec 03, 2025 | F113033 |
| G2307228 | Certificate of Analysis | Jun 07, 2023 | F113033 |
| G2307232 | Certificate of Analysis | Jun 07, 2023 | F113033 |
| G2307285 | Certificate of Analysis | Jun 07, 2023 | F113033 |
| G2307289 | Certificate of Analysis | Jun 07, 2023 | F113033 |
| C23181091 | Certificate of Analysis | Jan 31, 2023 | F113033 |
| C23181092 | Certificate of Analysis | Jan 31, 2023 | F113033 |
| C23181093 | Certificate of Analysis | Jan 31, 2023 | F113033 |
| C23181094 | Certificate of Analysis | Jan 31, 2023 | F113033 |
| E2311156 | Certificate of Analysis | Jan 31, 2023 | F113033 |
| Solubility | Soluble in water (10 mg/ml). |
|---|---|
| Melt Point(°C) | 150°C |
| Molecular Weight | 835.700 g/mol |
| XLogP3 | |
| Hydrogen Bond Donor Count | 0 |
| Hydrogen Bond Acceptor Count | 16 |
| Rotatable Bond Count | 8 |
| Exact Mass | 833.979 Da |
| Monoisotopic Mass | 831.982 Da |
| Topological Polar Surface Area | 234.000 Ų |
| Heavy Atom Count | 51 |
| Formal Charge | 0 |
| Complexity | 480.000 |
| Isotope Atom Count | 0 |
| Defined Atom Stereocenter Count | 0 |
| Undefined Atom Stereocenter Count | 0 |
| Defined Bond Stereocenter Count | 0 |
| Undefined Bond Stereocenter Count | 0 |
| The total count of all stereochemical bonds | 0 |
| Covalently-Bonded Unit Count | 5 |
| 1. Wang Lu, Mingwei Xia, Ziyue Tang, Yingquan Chen, Xianhua Wang, Haiping Yang, Hanping Chen. (2025) Synergetic regulation mechanism of K-assisted bamboo gasification for porous char and H2-rich syngas poly-generation. JOURNAL OF THE ENERGY INSTITUTE, [PMID:] [10.1016/j.joei.2025.102304] |
