Pyrabactin
{{Use dmy dates|date=January 2024}}
{{Chembox
| ImageFile = Pyrabactin.svg
| ImageSize = 200px
| PIN = 4-Bromo-N-[(pyridin-2-yl)methyl]naphthalene-1-sulfonamide
| OtherNames = 4-Bromo-N-(pyridin-2-ylmethyl)naphthalene-1-sulfonamide
|Section1={{Chembox Identifiers
| CASNo = 419538-69-5
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = L9PM5Q6DDW
| PubChem = 1125790
| ChemSpiderID = 958087
| SMILES = Brc2c1c(cccc1)c(cc2)S(=O)(=O)NCc3ncccc3
| InChI = 1/C16H13BrN2O2S/c17-15-8-9-16(14-7-2-1-6-13(14)15)22(20,21)19-11-12-5-3-4-10-18-12/h1-10,19H,11H2
| InChIKey = GJSDYQXOSHKOGX-UHFFFAOYAQ
| StdInChI = 1S/C16H13BrN2O2S/c17-15-8-9-16(14-7-2-1-6-13(14)15)22(20,21)19-11-12-5-3-4-10-18-12/h1-10,19H,11H2
| StdInChIKey = GJSDYQXOSHKOGX-UHFFFAOYSA-N
}}
|Section2={{Chembox Properties
| C=16 | H=13 | Br=1 | N=2 | O=2 | S=1
| Appearance = White to off-white powder[http://www.sigmaaldrich.com/catalog/product/sigma/b3438?lang=en®ion=US Pyrabactin], Sigma-Aldrich
| Density =
| MeltingPt =
| BoilingPt =
| Solubility =
| Solvent = DMSO
}}
|Section3={{Chembox Hazards
| MainHazards =
| FlashPt =
| AutoignitionPt =
}}
}}
Pyrabactin is a synthetic sulfonamide that mimics abscisic acid (ABA), a naturally produced stress hormone in plants that helps them cope with drought conditions by inhibiting growth. ABA can be manufactured for agricultural use; however, ABA is light-sensitive and costly to make. Pyrabactin is relatively inexpensive, easy to make, and not sensitive to light. Unlike ABA, pyrabactin activates only a few of the 14 ABA receptors in the plant needed for effective drought tolerance.[http://www.rsc.org/chemistryworld/News/2009/May/01050901.asp Organic compound comes to the aid of thirsty plants, Royal Society of Chemistry, 1 May 2009] Its role as an ABA mimic may make pyrabactin an important tool for protecting crops against drought and cold weather.[http://portal.acs.org/portal/acs/corg/content?_nfpb=true&_pageLabel=PP_ARTICLEMAIN&node_id=841&content_id=CNBP_023706&use_sec=true&sec_url_var=region1&__uuid=8cebf521-ab3c-49b4-9db7-51071bf18ac7 Pyrabactin – American Chemical Society][http://www.physorg.com/news160319874.html Synthetic chemical offers solution for crops facing drought]
The discovery of pyrabactin by Sean Cutler was named a breakthrough research of 2009 by Science magazine.[http://scienceblog.com/37837/growing-drought-tolerant-crops-inching-forward/ Growing drought-tolerant crops inching forward (Science Blog)]
Pyrabactin (for pyridyl containing ABA activator) is a naphthalene sulfonamide hypocotyl cell expansion inhibitor. A combination of genetic, transcriptomic and physiological evidence demonstrated that pyrabactin activates the ABA pathway in a manner very similar to ABA.{{Cite journal |last1=Melcher |first1=Karsten |last2=Xu |first2=Yong |last3=Ng |first3=Ley-Moy |last4=Zhou |first4=X Edward |last5=Soon |first5=Fen-Fen |last6=Chinnusamy |first6=Viswanathan |last7=Suino-Powell |first7=Kelly M |last8=Kovach |first8=Amanda |last9=Tham |first9=Fook S |last10=Cutler |first10=Sean R |last11=Li |first11=Jun |last12=Yong |first12=Eu-Leong |last13=Zhu |first13=Jian-Kang |last14=Xu |first14=H Eric |date=September 2010 |title=Identification and mechanism of ABA receptor antagonism |journal=Nature Structural & Molecular Biology |language=en |volume=17 |issue=9 |pages=1102–1108 |doi=10.1038/nsmb.1887 |issn=1545-9993 |pmc=2933329 |pmid=20729862 }} As such, pyrabactin is the first ABA agonist that is not an ABA analog and may ultimately lead to the development of a new family of synthetic plant growth regulators.