Cyclopyrimorate Chemical Properties

Boiling point:

533.3±50.0 °C(Predicted)

Density 

1.368±0.06 g/cm3(Predicted)

pka

-0.51±0.10(Predicted)

form 

Solid

color 

Off-white to light yellow

Cyclopyrimorate Usage And Synthesis

Uses

Cyclopyrimorate, a highly effective bleaching herbicide for weed control in rice fields, targets homogentisate solanesyltransferase (HST). HST is a downstream enzyme of 4-hydroxyphenylpyruvate dioxygenase in the plastoquinone (PQ) biosynthesis pathway[1][2].

Definition

ChEBI: Cyclopyrimorate is a member of the class of pyridazine that is 3-chloropyridazine which has been substituted at positions 5 and 6 by (morpholin-4-ylcarbonyl)oxy and 2-cyclopropyl-6-methylphenoxy groups, respectively. A selective herbicide used to control broad-leaved and grassy weeds in cereals and rice. It has a role as a herbicide, an agrochemical and an EC 2.5.1.117 (homogentisate solanesyltransferase) inhibitor. It is a member of pyridazines, a carbamate ester, a member of morpholines, an aromatic ether, a member of cyclopropanes and an organochlorine compound.

Mode of action

The mode of action of cyclopyrimorate is antagonistic inhibition of auxin-induced growth. Cyclopyrimorate caused bleaching symptoms in Arabidopsis thaliana similar to those caused by existing carotenoid biosynthesis inhibitors, mesotrione and norflurazon. However, cyclopyrimorate treatment resulted in significant accumulation of homogentisate and a reduction in the level of plastoquinone. A metabolite of cyclopyrimorate, des-morpholinocarbonyl cyclopyrimorate (DMC), was detected in plants. These data suggested that cyclopyrimorate and/or DMC inhibit homogentisate solanesyltransferase (HST), a downstream enzyme of 4-hydroxyphenylpyruvate dioxygenase in the plastoquinone biosynthesis pathway.

References

[1] Shino M, et al. In vivo and in vitro evidence for the inhibition of homogentisate solanesyltransferase by cyclopyrimorate. Pest Manag Sci. 2019 Nov 27. DOI:10.1002/ps.5698
[2] Shino M, et al. Action mechanism of bleaching herbicide cyclopyrimorate, a novel homogentisate solanesyltransferase inhibitor. J Pestic Sci. 2018 Nov 20;43(4):233-239. DOI:10.1584/jpestics.D18-008
[3] MAMIKO SHINO. Action mechanism of bleaching herbicide cyclopyrimorate, a novel homogentisate solanesyltransferase inhibitor.[J]. Journal of Pesticide Science, 2018, 43 4: 233-239. DOI:10.1584/jpestics.D18-008.