(Redirected from Aminotriazole)

3-Amino-1,2,4-triazole (3-AT) is a heterocyclic organic compound that consists of a 1,2,4-triazole substituted with an amino group.

IUPAC name
Other names
  • 61-82-5 checkY
3D model (JSmol)
Abbreviations 3-AT
ECHA InfoCard 100.000.474 Edit this at Wikidata
EC Number
  • 200-521-5
MeSH Amitrole
RTECS number
  • XZ3850000
  • InChI=1S/C2H4N4/c3-2-4-1-5-6-2/h1H,(H3,3,4,5,6) checkY
  • InChI=1/C2H4N4/c3-2-4-1-5-6-2/h1H,(H3,3,4,5,6)
  • n1c[nH]nc1N
Molar mass 84.08
Appearance colorless/white crystals or powder[2]
Odor odorless
Density 1.138 g/mol
Melting point 157 to 159 °C (315 to 318 °F; 430 to 432 K)
Boiling point 347
28 g/100 mL
Solubility soluble in acetonirile, chloroform, ethanol, methanol, methylene chloride
negligible in ethyl acetate
Vapor pressure 3.13x10−9 mmHg
Main hazards potential occupational carcinogen
GHS pictograms GHS08: Health hazardGHS09: Environmental hazard
GHS Signal word Warning
H361, H373, H411
P201, P202, P260, P273, P281, P308+313, P314, P391, P405, P501
NFPA 704 (fire diamond)
Flash point Non-flammable
Lethal dose or concentration (LD, LC):
1,100 to 2,500 mg/kg
NIOSH (US health exposure limits):
PEL (Permissible)
REL (Recommended)
Ca TWA 0.2 mg/m3[2]
IDLH (Immediate danger)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Infobox references

3-AT is a competitive inhibitor of the product of the HIS3 gene, imidazoleglycerol-phosphate dehydratase.[3][4] Imidazoleglycerol-phosphate dehydratase is an enzyme catalyzing the sixth step of histidine production.[5]

3-AT is also a nonselective systemic triazole herbicide used on nonfood croplands to control annual grasses and broadleaf and aquatic weeds. It is not used on food crops because of its carcinogenic properties. As an herbicide, it is known as aminotriazole, amitrole or amitrol.

Amitrol was included in a biocide ban proposed by the Swedish Chemicals Agency[6] and approved by the European Parliament on January 13, 2009.[7]

Applications in microbiologyEdit

By applying 3-AT to a yeast cell culture which is dependent upon a plasmid containing HIS3 to produce histidine (i.e. its own HIS3 analogue is not present or nonfunctional), an increased level of HIS3 expression is required in order for the yeast cell to survive. This has proved useful in various two-hybrid system, where a high-affinity binding between two proteins (i.e., higher expression of the HIS3 gene) will allow the yeast cell to survive in media containing higher concentrations of 3-AT. This selection process is performed using selective media, containing no histidine.

1959 cranberry contaminationEdit

On November 9, 1959, the secretary of the United States Department of Health, Education, and Welfare Arthur S. Flemming announced that some of the 1959 crop was tainted with traces of the herbicide aminotriazole.[8] The market for cranberries collapsed and growers lost millions of dollars.[9] However, Ocean Spray recovered by expanding the market for cranberry juice, which, although widely available for sale, was before then not popular. This ensured cranberry growers would not have to rely mostly on Thanksgiving and Christmas for sales, which was the case until the notorious 1959 incident.


  1. ^ EXTOXNET – Herbicide fact sheet for amitrole
  2. ^ a b c d NIOSH Pocket Guide to Chemical Hazards. "#0027". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ Brennan MB, Struhl K (1980). "Mechanisms of increasing expression of a yeast gene in Escherichia coli". J. Mol. Biol. 136 (3): 333–8. doi:10.1016/0022-2836(80)90377-0. PMID 6990004.
  4. ^ Joung JK, Ramm EI, Pabo CO (2000). "A bacterial two-hybrid selection system for studying protein-DNA and protein-protein interactions". Proc. Natl. Acad. Sci. U.S.A. 97 (13): 7382–7. Bibcode:2000PNAS...97.7382J. doi:10.1073/pnas.110149297. PMC 16554. PMID 10852947.
  5. ^ "Yeastgenome.org". Archived from the original on 2006-05-05. Retrieved 2006-12-01.
  6. ^ "Interpretation of criteria for approval of active substances in the proposed EU plant protection regulation". Swedish Chemicals Agency (KemI). 2008-09-23. Archived from the original on 1 January 2009. Retrieved 2009-01-14.
  7. ^ "MEPs approve pesticides legislation". 2009-01-13. Archived from the original on 25 January 2009. Retrieved 2009-01-14.
  8. ^ "Safe Cranberries to Go on Sale". Dubuque Telegraph-Herald. 19 November 1959. Retrieved 10 February 2012.
  9. ^ New York Times website - Opinion section