Indole-3-acetic acid
2027822
205934322
2008-04-16T02:22:38Z
WriterHound
266293
formatting
{{Chembox new
|ImageFile=Indol-3-ylacetic acid2.svg
|ImageSize=
|IUPACName=2-(1H-indol-3-yl)acetic acid
|OtherNames=Indole-3-acetic acid,<br>indolylacetic acid,<br>indoleacetic acid,<br>heteroauxin,<br>IAA
|Section1= {{Chembox Identifiers
| CASNo=87-51-4
| PubChem=802
| SMILES=C1=CC=C2C(=C1) C(=CN2)CC(=O)O
}}
|Section2= {{Chembox Properties
| Formula=C<sub>10</sub>H<sub>9</sub>NO<sub>2</sub>
| MolarMass=175.184
| Appearance=
| Density=
| MeltingPt=168-170 °C (441-443 K)
| BoilingPt=
| Solubility=
}}
|Section3= {{Chembox Hazards
| MainHazards=
| FlashPt=
| Autoignition=
}}
}}
'''Indole-3-acetic acid''', also known as IAA, is a member of the group of [[phytohormone]]s called [[auxin]]s. IAA is generally considered to be the most important native auxin.
== Auxin ==
{{main|Auxin}}
It is produced in cells in the [[apex]] ([[bud]]) and young leaves of a [[plant]]. Plant cells synthesize IAA from [[tryptophan]]. It has many different effects, as all auxins do, such as inducing [[Cell (biology)|cell]] elongation and [[cell division]] with all subsequent results for plant growth and development.
There are less expensive and [[metabolism|metabolically]] stable synthetic [[auxin]] analogs on the market for use in [[horticulture]], such as [[indole-3-butyric acid]] (IBA) and [[1-Naphthaleneacetic acid|1-naphthaleneacetic acid]] (NAA).
Studies of IAA in the 1940s led to the development of the [[phenoxy herbicide]]s [[2,4-dichlorophenoxyacetic acid]] (2,4-D) and [[2,4,5-trichlorophenoxyacetic acid]] (2,4,5-T). Like IBA and NAA, 2,4-D and 2,4,5-T are metabolically and environmentally more stable analogs of IAA. However, when sprayed on broad-leaf dicot plants, they induce rapid, uncontrolled growth, eventually killing them. First introduced in 1946, these herbicides were in widespread use in [[agriculture]] by the middle of the [[1950s]].
== Chemical properties of IAA ==
IAA can be produced by the reaction of [[indole]] with potassium glycolate at 250 C, but this compound is chemically unstable in particular when exposed to light or changing temperature.
== See also ==
* [[Auxin]]
* [[Phytohormone]]
* [[Indole]]
* [[Acetic acid]]
==Additional images==
<gallery>
Image:Indol2.svg|[[Indole]]
Image:Acetic-acid-2D-skeletal.svg|[[Acetic acid]]
</gallery>
==External links==
{{Plant_hormones}}
[[Category:Auxins]]
[[Category:Plant physiology]]
[[Category:Aromatic compounds]]
[[Category:Carboxylic acids]]
[[Category:Indoles]]
[[de:Indol-3-essigsäure]]
[[es:Ácido indolacético]]
[[fr:Acide indole 3-acétique]]
[[pl:Kwas indolilooctowy]]
[[ru:Гетероауксин]]