Absorption, Distribution and Excretion
Male and female Fischer rats were dosed orally by gavage with alpha-14C-/cyhalofop-butyl/ (radiochemical purity: >97%) or beta-14C-/cyhalofop-butyl/ (radiochemical purity: > 97%). In Groups I and II, 5 animals/sex/dose were treated with 1 or 50 mg/kg of alpha-14C-/cyhalofop-butyl/ and urine and feces samples were collected (Group I) or blood samples (Group II) for 7 days. For Group III, bile was collected for 24 hours from 5 rats/sex/group which had been treated with either 1 mg/kg of alpha-14C-/cyhalofop-butyl/ or beta-14C-/cyhalofop-butyl/. In Group IV, 5 animals/sex/group/time point were treated with 1 or 50 mg/kg of alpha-14C-/cyhalofop-butyl/ and euthanized at 4 time points over a 7 day period for a tissue distribution study. The radiolabel was excreted predominately in the urine (86 to 94% of the administered dose) with nearly all of that amount collected in the first 24 hours post-dose. There was no apparent difference between sexes or in the dosing regimens. Peak blood levels for the 1 mg/kg treated animals were at 2 hours for the males and 0.5 hours for the females. For the 50 mg/kg treated animals, peak levels were at 4 hours for the males and at 2 hours at the females. In the bile duct cannulated animals, less of the administered dose was apparently absorbed. For the alpha-14C-/cyhalofop-butyl/ treated animals, 29 and 17% of the administered dose was recovered in the stomach contents of the males and females, respectively, at 24 hours postdosing. Otherwise, 27 and 36% was recovered in the urine and 24 and 18% was collected in the bile of the males and females, respectively. Similarly, for the beta-14C-/cyhalofop-butyl/ treated animals, 40 and 38% of the administered dose was recovered in the stomach contents, 21 and 37% in the urine and 12 to 17% in the bile of the males and females, respectively at 24 hours post-dose. The radiolabel was predominately distributed in the plasma, kidneys, liver and stomach with peak tissue levels noted at 2 hours for the males and 0.5 hours for the females in the 1 mg/kg group, and 4 hours for the males and 2 hours for the females in the 50 mg/kg group. The pharmacokinetic parameters were as follows: dose 1 mg/kg, Cmax, males, 1.23 to 1.30 ug eq./mL, females, 0.58 to 0.73 ug eq./mL, Tmax, males, 2 hours, females, 0.5 hours, half-life, males, 3.0 to 3.1 hours, females, 1.4 to 3.9 hours.
On the base of the studies conducted, the mean predicted human dermal absorption values for the concentrate and spray are 1.3% and 11%, while the maximum predicted dermal absorption values for the concentrate and spray are 1.5% and 14%, respectively.

---

Metabolism / Metabolites
Rats, dogs, ruminants and poultry readily metabolise cyhalofop-butyl by hydrolysis to the acid. Depending on the animal, the acid may also break down to other metabolites. The acid and any additional degradates are then rapidly excreted. Residue levels of cyhalofop-butyl and its metabolites are low in milk, eggs and tissues.
Two male beagle dogs/group were dosed orally by gavage with 1 mg/kg of alpha-14C-/cyhalofop-butyl/ (radiochemical purity: >97%) mixed with unlabeled /cyhalofop-butyl/ (purity: 97%). ...The test material was hydrolyzed to n-butanol and /cyhalofop-butyl acid/, constituting 80% and 66% of the recovered radiolabel in the urine and feces, respectively, during the first 48 hours post-dose. In the feces, acid was further decarboxylated to form a diphenol (DP). This moiety constituted 13.2% of the recovered radiolabel. Treatment of the unidentified radiolabeled compounds with b-glucuronidase/arylsulfatase resulted in an increase of the acid and DP fractions with a corresponding decrease in these unidentified compounds.
Organic nitriles are converted into cyanide ions through the action of cytochrome P450 enzymes in the liver. Cyanide is rapidly absorbed and distributed throughout the body. Cyanide is mainly metabolized into thiocyanate by either rhodanese or 3-mercaptopyruvate sulfur transferase. Cyanide metabolites are excreted in the urine. (L96)

Cyhalofop-butyl is an aromatic ether.
Cyhalofop-butyl is an aryloxyphenoxy propionic acid herbicide. It is a graminicide (kills grass and weeds) used for postemergence grass weed control in rice

C20H20FNO4

357.3814

357.137

122008-85-9

180089

White crystalline solid
Waxy off-white to buff colored solid (technical); clear amber liquid (end-use)

1.2±0.1 g/cm3

449.1±45.0 °C at 760 mmHg

49.5ºC

225.4±28.7 °C

0.0±1.1 mmHg at 25°C

1.551

4.4

0

6

9

26

483

1

FC1C([H])=C(C#N)C([H])=C([H])C=1OC1C([H])=C([H])C(=C([H])C=1[H])O[C@]([H])(C([H])([H])[H])C(=O)OC([H])([H])C([H])([H])C([H])([H])C([H])([H])[H]

TYIYMOAHACZAMQ-CQSZACIVSA-N

InChI=1S/C20H20FNO4/c1-3-4-11-24-20(23)14(2)25-16-6-8-17(9-7-16)26-19-10-5-15(13-22)12-18(19)21/h5-10,12,14H,3-4,11H2,1-2H3/t14-/m1/s1

butyl (2R)-2-[4-(4-cyano-2-fluorophenoxy)phenoxy]propanoate

XDE-537; XDE 537; Cyhalofop-butyl

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~250 mg/mL (~699.54 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

---

Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

View More

Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

---

Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

View More

Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

---

Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

---

 (Please use freshly prepared in vivo formulations for optimal results.)