3,5-dinitrosalicylic acid

Structural formula
General
Surname	3,5-dinitrosalicylic acid
other names	2-hydroxy-3,5-dinitrobenzoic acid ( IUPAC ) ; DNS; DNSA;
Molecular formula	C 7 H 4 N 2 O 7
Brief description	light yellow crystals with a faint odor
External identifiers / databases
EC number	210-204-3
ECHA InfoCard	100.009.278
PubChem	11873
ChemSpider	11380
Wikidata	Q223030
properties
Molar mass	228.12 g mol −1
Physical state	firmly
density	1.70–1.72 g cm −3 (monohydrate)
Melting point	170-174 ° C
pK s value	pK s 1 = 2.96; pK s 2 = 7.61;
solubility	soluble in water: 13.55 g · l -1 (21 ° C); soluble in ethanol , diethyl ether and benzene ;
safety instructions
GHS labeling of hazardous substances Caution
H and P phrases	H: 302-315-319-335
	P: 280-301 + 330 + 331-312-302 + 352-304 + 340-501
Toxicological data	860 mg kg −1 ( LD 50 , rat , oral )
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

3,5-Dinitrosalicylic acid (DNS) is a phenolic acid , which gives a typical color reaction with reducing sugars or other reducing molecules .

Presentation and extraction

3,5-dinitrosalicylic acid, by the nitration of salicylic acid by means of nitrating acid are prepared. An alternative method uses the combination of nitric acid and acetic acid as a nitrating reagent, with acetyl nitrate reacting as an intermediate .

properties

3,5-dinitrosalicylic acid is a carboxylic acid having a pK _s value of 2.96 for the carboxy group and 7.61 for the phenolic OH group. The octanol-water partition coefficient (log K _OW ) is 1.71. It was possible to isolate two different crystal forms from the monohydrate , whose densities also differ with 1.702 g / cm ³ (crystallized from ethanol ) and 1.719 g / cm ³ (crystallized from water).

use

With reducing sugars , 3,5-dinitrosalicylic acid is reduced to 3-amino-5-nitrosalicylic acid, which strongly absorbs light at 540 nm . During this reaction, the color of the solution changes from orange-yellow to red.

The colorimetric reaction was first introduced to determine reducing substances in urine and has been widely used since then, e.g. B. to quantify carbohydrates in blood . Mainly using the detection reaction when α- amylase - assay . The method combines the oxidation of a carbonyl compound with the reduction of a nitro group in 3,5-dinitrosalicylic acid under alkaline conditions. An alkaline reaction solution with 2% DNS and 2% Na ₂ CO _{3 is used} . Other urine components do not have a disruptive effect.

Today, however, enzymatic methods are usually preferred to determination with 3,5-dinitrosalicylic acid because they are more specific.

Web links

Commons : 3,5-Dinitrosalicylic Acid - Collection of Pictures, Videos and Audio Files

Entry for 3,5-Dinitrosalicylic acid in the ChemIDplus database of the United States National Library of Medicine (NLM) .
Laboratory use of 3,5-dinitrosalicylic acid (in English) Department of Chemical Engineering, University of Maryland .

Individual evidence

↑ ^a ^b ^c ^d data sheet 3,5-dinitrosalicylic acid (PDF) from Merck , accessed on October 17, 2017.
↑ ^a ^b V. S. Senthil Kumar; Srinivasan S. Kuduva; Gautam R. Desiraju: Pseudopolymorphs of 3,5-dinitrosalicylic acid , in: J. Chem. Soc., Perkin Trans. 2 , 1999 , pp. 1069-1073; doi : 10.1039 / a902134e ; PDF .
↑ ^a ^b S. S. Dube; SS Dhindsa: Dissociation constants of 3,5-dinitrosalicylic acid , Proceedings of the Indian Academy of Sciences, Section A, 642, 1968.
↑ Alexander Apelbalt; Emanuel Manzurola: Solubilities of o-acetylsalicylic, 4-aminosalicylic, 3,5-dinitrosalicylic, and p-toluic acid, and magnesium-DL-aspartate in water from T = (278 to 348) K , in: J. Chem. Thermodyn . , 1999 , 31 (1) , pp. 85-91; doi : 10.1006 / jcht.1998.0424 .
↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-290.
↑ ^a ^b Entry on 3,5-dinitrosalicylic acid in the GESTIS substance database of the IFA , accessed on January 20, 2020(JavaScript required) .
↑ Thiel, W .; Mayer, R .; Jauer, E.-A .; Modrow, H .; Dost, H .: Synthesis and Spectral Characterization of Blue Dyes of the Benzene Series ; in: J. Prakt. Chem. (Leipzig) 328 (1986), pp. 497-514, doi : 10.1002 / prac.19863280406 .
↑ Andreozzi, R .; Caprio, V .; Di Somma, I .; Sanchirico, R .: Kinetic and safety assessment for salicylic acid nitration by nitric acid / acetic acid system in J. Hazard. Mat. A134 (2006), pp. 1-7, doi : 10.1016 / j.jhazmat.2005.10.037 .
↑ JB Sumner: Dinitrosalicylic acid: a reagent for the estimation of sugar in normal and diabetic urine. In: Journal of Biological Chemistry (1921), Volume 47, p. 5.
↑ United States Patent 3869348 Determination of amylase , Pierce Chemical Company (Rockford, IL) 1975.
↑ James B. Sumner, Charles V. Noback: The estimation of sugar in diabetic urine, using dinitrosalicylic acid , in: J. Biol. Chem. , 1924 , 62 , pp. 287-290; PDF .
↑ James B. Sumner: Dinitrosalicylic Acid: A Reagent for the Estimation of Sugar in Normal and Diabetic Urine , in: J. Biol. Chem. , 1921 , 47 , pp. 5-9; PDF .
↑ Gail Lorenz Miller: Use of Dinitrosalicylic Acid Reagent for Determination of Reducing Sugar , in: Anal. Chem. , 1959 , 31 (3) , pp. 426-428; doi : 10.1021 / ac60147a030 .

[Merck_SDB-1] ta sheet 3,5-dinitrosalicylic acid (PDF) from Merck , accessed on October 17, 2017.

[kumar-2] V. S. Senthil Kumar; Srinivasan S. Kuduva; Gautam R. Desiraju: Pseudopolymorphs of 3,5-dinitrosalicylic acid , in: J. Chem. Soc., Perkin Trans. 2 , 1999 , pp. 1069-1073; doi : 10.1039 / a902134e ; PDF .

[Dube-3] S. S. Dube; SS Dhindsa: Dissociation constants of 3,5-dinitrosalicylic acid , Proceedings of the Indian Academy of Sciences, Section A, 642, 1968.

[4] Alexander Apelbalt; Emanuel Manzurola: Solubilities of o-acetylsalicylic, 4-aminosalicylic, 3,5-dinitrosalicylic, and p-toluic acid, and magnesium-DL-aspartate in water from T = (278 to 348) K , in: J. Chem. Thermodyn . , 1999 , 31 (1) , pp. 85-91; doi : 10.1006 / jcht.1998.0424 .

[5] David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-290.

[Sigma-6] Entry on 3,5-dinitrosalicylic acid in the GESTIS substance database of the IFA , accessed on January 20, 2020(JavaScript required) .

[Thiel-7] Thiel, W .; Mayer, R .; Jauer, E.-A .; Modrow, H .; Dost, H .: Synthesis and Spectral Characterization of Blue Dyes of the Benzene Series ; in: J. Prakt. Chem. (Leipzig) 328 (1986), pp. 497-514, doi : 10.1002 / prac.19863280406 .

[Andreozzi-8] Andreozzi, R .; Caprio, V .; Di Somma, I .; Sanchirico, R .: Kinetic and safety assessment for salicylic acid nitration by nitric acid / acetic acid system in J. Hazard. Mat. A134 (2006), pp. 1-7, doi : 10.1016 / j.jhazmat.2005.10.037 .

[9] JB Sumner: Dinitrosalicylic acid: a reagent for the estimation of sugar in normal and diabetic urine. In: Journal of Biological Chemistry (1921), Volume 47, p. 5.

[10] United States Patent 3869348 Determination of amylase , Pierce Chemical Company (Rockford, IL) 1975.

[11] James B. Sumner, Charles V. Noback: The estimation of sugar in diabetic urine, using dinitrosalicylic acid , in: J. Biol. Chem. , 1924 , 62 , pp. 287-290; PDF .

[12] James B. Sumner: Dinitrosalicylic Acid: A Reagent for the Estimation of Sugar in Normal and Diabetic Urine , in: J. Biol. Chem. , 1921 , 47 , pp. 5-9; PDF .

[13] Gail Lorenz Miller: Use of Dinitrosalicylic Acid Reagent for Determination of Reducing Sugar , in: Anal. Chem. , 1959 , 31 (3) , pp. 426-428; doi : 10.1021 / ac60147a030 .