Cyazofamid Explained

Cyazofamid is a fungicide that is highly-specific in controlling oomycete plant pathogens such as Phytophthora infestans, the organism which causes late blight in potato. Its mode of action is thought to involve binding to the Q_i center of Coenzyme Q – cytochrome c reductase.^{[1] [2]}

Cyazofamid is most often sold under the brand name Ranman.^[3]

Synthesis

Processes to manufacture cyazofamid were disclosed in patents from Ishihara Sangyo Kaisha, Ltd.^[4] An acetophenone derivative was first treated with aqueous glyoxal and hydroxylamine to form an oxime-substituted imidazole ring system. This intermediate was treated with thionyl chloride and disulfur dichloride to convert the oxime to a cyano group and chlorinate the imidazole in the position next to the phenyl ring. Finally, treatment with dimethylsulfamoyl chloride gave cyazofamid, with the desired regiochemistry. This placed the sulfamoyl group on the nitrogen adjacent to the phenyl ring rather than the chlorine atom. The structure of the fungicide has been confirmed by X-ray crystallography.^[5]

Further reading

• Ohshima . Takeshi . Komyoji . Terumasa . Mitani . Shigeru . Matsuo . Norifusa . Nakajima . Toshio . Development of a Novel Fungicide, Cyazofamid . . . 29 . 2 . 2004 . 1348-589X . 1349-0923 . 10.1584/jpestics.29.147 . 147–152 . 84909424 . ja. free . AGRIS id JP2004007452. CiNii NAID 130004444938. ISSN-L 0385-1559.
• Anastassiadou . Maria . Arena . Maria . Auteri . Domenica . Brancato . Alba . Bura . Laszlo . Carrasco Cabrera . Luis . Chaideftou . Eugenia . Chiusolo . Arianna . Crivellente . Federica . De Lentdecker . Chloe . Egsmose . Mark . Fait . Gabriella . Greco . Luna . Ippolito . Alessio . Istace . Frederique . Jarrah . Samira . Kardassi . Dimitra . Leuschner . Renata . Lostia . Alfonso . Lythgo . Christopher . Magrans . Oriol . Mangas . Iris . Miron . Ileana . Molnar . Tunde . Padovani . Laura . Parra Morte . Juan Manuel . Pedersen . Ragnor . Reich . Hermine . Santos . Miguel . Sharp . Rachel . Sturma . Juergen . Szentes . Csaba . Terron . Andrea . Tiramani . Manuela . Vagenende . Benedicte . Villamar-Bouza . Laura . Updated peer review of the pesticide risk assessment of the active substance cyazofamid . . European Food Safety Authority (Wiley) . 18 . 9 . 2020 . 1831-4732 . 10.2903/j.efsa.2020.6232 . 1-25. 32994826 . 7507320 . free .

External links

• Web site: Cyazofamid . PubChem . 2021-05-17.
• Web site: Pesticides - Fact Sheet for Cyazofamid - US EPA. US EPA.

Notes and References

1. Mitani . Shigeru . Araki . Satoshi . Takii . Yasuko . Ohshima . Takeshi . Matsuo . Norifusa . Miyoshi . Hideto . The Biochemical Mode of Action of the Novel Selective Fungicide Cyazofamid: Specific Inhibition of Mitochondrial Complex III in Phythium spinosum . Pesticide Biochemistry and Physiology . October 2001 . 71 . 2 . 107–115 . 10.1006/pest.2001.2569.
2. Mitani . Shigeru . Araki . Satoshi . Yamaguchi . Tomona . Takii . Yasuko . Ohshima . Takeshi . Matsuo . Norifusa . Antifungal Activity of the Novel Fungicide Cyazofamid against Phytophthora infestans and Other Plant Pathogenic Fungi in Vitro . Pesticide Biochemistry and Physiology . June 2001 . 70 . 2 . 92–99 . 10.1006/pest.2001.2541.
3. Web site: Fungicides . ISKBC – ISK Biosciences CORPORATION . 2021-05-25.
4. US . 5869683 . patent . 1999-02-09 . 1997-11-03 . 1994-09-08 . Jonishi H. et al. . Processes for producing 1-substituted-2-cyanoimidazole compounds . Ishihara Sangyo Kaisha Ltd..
5. 10.5517/cc115rlk . free . 2013 . Ning . Bin-Ke . Xu . Cheng . Li . Zong-Ying . Wang . Yue-Mei . Sun . Qiao-Nan . CCDC 958848: Experimental Crystal Structure Determination . Cambridge Crystallographic Data Centre . Cambridge Structural Database.