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  • D9132 - 2,2-Diphenyl-1-picrylhydrazyl

D9132 Sigma-Aldrich


Synonym: 1,1-Diphenyl-2-picrylhydrazyl radical, 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl, DPPH

  • CAS Number 1898-66-4

  • Empirical Formula (Hill Notation) C18H12N5O6

  • Molecular Weight 394.32

  •  Beilstein/REAXYS Number 1846081

  •  EC Number 217-591-8

  •  MDL number MFCD00007231

  •  PubChem Substance ID 57654141

  •  NACRES NA.22



Related Categories Chemical Synthesis, Picrylhydrazyl Derivatives, Radical Chemistry, Stable Radicals, Synthetic Reagents More...
Quality Level   100
color   green
mp   ~135 °C (dec.) (lit.)
storage temp.   2-8°C
SMILES string   [O-][N+](=O)c1cc(c([N]N(c2ccccc2)c3ccccc3)c(c1)[N+]([O-])=O)[N+]([O-])=O
InChI   1S/C18H12N5O6/c24-21(25)15-11-16(22(26)27)18(17(12-15)23(28)29)19-20(13-7-3-1-4-8-13)14-9-5-2-6-10-14/h1-12H


General description

2,2-diphenyl-1-picrylhydrazyl is a free radical, which shows hydrogen acceptor ability towards antioxidants. Hence, it is commonly used in DPPH assay for measuring the antioxidant activity of different natural samples such as wine, fruits, herbal tea etc.


1, 5 g in glass bottle

Other Notes

Free radical

Safety & Documentation

Safety Information

Signal word 
NONH for all modes of transport
WGK Germany 
Flash Point(F) 
Not applicable
Flash Point(C) 
Not applicable


Certificate of Analysis (COA)

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Certificate of Origin (COO)

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Frequently Asked Questions

Which document(s) contains shelf-life or expiration date information for a given product?
If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.
How do I get lot-specific information or a Certificate of Analysis?
The lot specific COA document can be found by entering the lot number above under the "Documents" section.
How do I find price and availability?
There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote. USA customers: 1-800-325-3010 or view local office numbers.
What is the Department of Transportation shipping information for this product?
Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.
What is the solubility of 2,2-Diphenyl-1-picrylhydrazyl, DPPH, Product D9132?
We would expect this material to be soluble in chloroform and methanol. Quality control testing shows that a concentration of about 50mg/mL in chloroform can be achieved.
At what wavelength is the absorbance maximum (lambda max) for 2,2-Diphenyl-1-picrylhydrazyl, DPPH, Product D9132?
Using chloroform as the solvent, the lambda max is approximately 332 nm.
What is the extinction coefficient of 2,2-Diphenyl-1-picrylhydrazyl, DPPH, Product D9132?
The millimolar extinction coefficient (EmM) has been reported to be 19.07 in chloroform, measured at a wavelength of 332 nm. Reference: Organic Electronic Spectra Data (OESD), 1, p. 753 (1946-1952).
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