Hymexazol

Hymexazol

噁霉灵

5-methylisoxazol-3-ol
or
5-methyl-1,2-oxazol-3-ol

5-methyl-3(2H)-isoxazolone

10004-44-1

C₄H₅NO₂

Fungicides > Oxazole fungicides

Fungicide
Hymexazol is applied as a soil drench, a seed dressing or by soil incorporation. It is translocated acropetally in crops. It is believed that the compound has a synergistic effect on endogenous auxin, thereby promoting root growth. This in turn leads to increased cold resistance, reduced flooding damage and a reduction in the phytotoxic effects of some herbicides. The product can be used as a seed treatment to control soil-borne diseases such as Aphanomyces cochlioides, for which no alternatives are available, in sugar beet.

Hymexazol is non-phytotoxic to target crops.

CropUses:
rice, sugar beet, vegetables, tomatoes, ornamentals, forestry, cucumber, watermelon

tomatoes	8,000 g ai/ha
sugar beet	45 g ai/unit

Propamocarb hydrochloride+Hymexazol
Prochloraz+Hymexazol
Hymexazol+thiram
Hymexazol+Tetramycin
Hymexazol+metalaxyl
Hymexazol+isoprothiolane
Fludioxonil+Hymexazol
Azoxystrobin+Hymexazol

Molecular weight:99.1g/mol; Physical form:Tech. forms colourless crystals. Density:0.551; Composition:Tech. is 99% pure. Melting point:86-87℃; Flash point:205℃; Vapour pressure:182 mPa (25℃); Henry constant:2.77 × 10-4 Pa m3 mol-1 (20℃); Partition coefficient(n-octanol and water):logP = 0.480 (unstated pH); pKa:5.92, weak acid; Solubility:In water 65.1 (pure), 58.2 ( pH 3), 67.8 ( pH 9) (all in g/l, 20℃). In acetone 730, dichloromethane 602, ethyl acetate 437, hexane 12.2, methanol 968, toluene 176 (all in g/l, 20℃).; Stability:Stable under alkaline conditions, and relatively stable under acidic conditions. Stable to light and heat.

Oral:Acute oral LD₅₀ for male rats 4678, female rats 3909, male mice 2148, female mice 1968 mg/ kg. Percutaneous:Acute percutaneous LD₅₀ for male and female rats >10 000, male and female rabbits >2000 mg/kg. Irritant to eyes and mucous membranes; not irritant to skin. Inhalation: LC₅₀ (4 h   14 d) for rats >2.47 mg/l.

Ecotoxicology:
Algae: NOEL 29 mg/l.Bees:Not hazardous to bees. LD₅₀ (48 h, oral and contact) >100 μg/bee. Birds:Acute oral LD₅₀ for Japanese quail 1085, mallard ducks >2000 mg/ kg.Daphnia: EC₅₀ (48 h) 28 mg/l.Fish: LC₅₀ (96 h) for rainbow trout 460; LC₅₀ (48 h) for carp 165 mg/l.Worms: LC₅₀ (14 d) for earthworms (Eisenia foetida) >15.7 ppm.

Environmental fate:
Animals:In mammals, following oral administration, hymexazol is metabolised to glucuronides.Soil:In soil, hymexazol is degraded to 5-methyl-2-(3H)-oxazolone, DT₅₀ 2-25 d.Plant:In plants, hymexazol undergoes degradation to O- and N- glucosides.

Signal Word:CAUTION; Hazard Class:III(Slightly hazardous)