Three classes of GA-biosynthesis inhibitors that affect different steps in the pathway are known. A well-known example of this class of retardant is chlormequat chloride (CCC), which is used on a large scale as an anti-lodging agent in wheat. Certain heterocyclic nitrogen-containing compounds, including ancymidol, paclobutrazol and tetcyclasis, are efficient inhibitors of ent-kaurene oxidase. The third group of inhibitors comprises acylcyclohexanedione derivatives, such as prohexadione, that target the 2-oxoglutarate-dependent dioxygenases.

CHLOROMEQUAT CHLORIDE (CCC, Cycocel) [(2-chloroethyl)trimethylammonium chloride]

MW 158.07; CRYSTALLINE; purity > 97% (HPLC)
R: 21/22, S: 36/37; CAS: 999-81-5; C5H13Cl2N
	019 3091	1	g
	019 3092	5	g
	019 3093	25	g

PACLOBUTRAZOL [1-tert-butyl-2-(p-chlorobenzyl)-2-(1,2,4-triazol-1-yl)ethanol]

MW 293.80; crystalline; purity > 97% (HPLC)
R:22, S:36; CAS: 76738-62-0; C15H20ClN3O
	019 3101	100	mg
	019 3102	500	mg
	019 3103	1	g

MEPIQUAT CHLORIDE [1,1-dimethylpiperidinium chloride]

MW 149.66; crystalline; purity > 97% (HPLC)
R: 22, 52/53, S: 61; CAS: 24307-26-4; C7H16ClN
	019 3111	100	mg
	019 3112	500	mg
	019 3113	1	g

UNICONAZOLE [1-tert-butyl-2-(p-chlorobenzylidene)-2-(1,3,5-triazol-1-yl)ethanol]

MW 291.78; crystalline; purity > 97% (HPLC)
S:26, 36; CAS: 83657-22-1; C15H18ClN3O
	019 3121	100	mg
	019 3122	500	mg
	019 3123	1	g

ANCYMIDOL [1-cyclopropyl-1-(4’-methoxyphenyl)-1-(5’-pyrimidine)methanol]

MW 256.31; crystalline; purity > 97% (HPLC)
S:26, 36; CAS: 12771-68-5; C15H16N2O2
	019 3131	100	mg
	019 3132	500	mg
	019 3133	1	g

FLURPRIMIDOL [1-(4’-trifluoromethoxy)-1-(5’-pyrimidine)isobutanol]

MW 312.29; crystalline; purity > 97% (HPLC)
R: 21/22, 52, S:26, 36; CAS: 56425-91-3; C15H15F3N2O2
	019 3141	100	mg
	019 3142	500	mg
	019 3143	1	g