Metazosulfuron is a herbicide used in paddy fields to control annual and perennial weeds.
The commercial production of metazosulfuron involves the synthesis of a complex molecule featuring a pyrazole ring, a dimethoxypyrimidine moiety, and a sulfonylurea linkage. The process includes heterocyclic ring formation, sulfonylation, and urea coupling, followed by purification to yield a white crystalline powder. The technical material is typically a racemic mixture.
Metazosulfuron is a sulfonylurea from the pyrazosulfuron class developed under the trade name ALTAIR® by Nissan for the Japanese and South Korean markets. It was first launched in Korea in 2012, one year later in Japan, and was registered in China in 2016. It shows excellent herbicidal activity against Echinochloa spp. annual and perennial weeds including sulfonylurea-resistant biotypes in paddy fields at 60–120 g a.i. ha−1 with good crop safety to rice.
An acetolactate synthase (ALS) inhibitor