Daphnia growth rate is slowed down by methoprene, and a single concentration response line with a threshold of 12.6 nM is shown. A 2-segment line with thresholds of 4.2 and 0.21 nM, respectively, was shown by the response curve for mephenyl, which reduced molting frequency in a concentration-dependent manner. Methoprene also had an apparent concentration-dependent effect on the endpoint associated with reproductive maturity, the time to first oviposition, with a NOEC of 32 nM. Fecundity is decreased by methoprene based on a 2-segment line threshold of 24 and

Absorption, Distribution and Excretion
When (14)C-methoxyprotein was administered orally to rats, slightly less than 20% of the drug was excreted in the urine within 5 days, with a similar amount excreted in the feces. Nearly 40% was excreted as (14)CO2. Approximately 17% of the drug remained in the body. The highest concentrations were found in the liver (84.5 ppm), kidneys (29 ppm), lungs (26 ppm), fat (36.5 ppm), and adrenal cortex (12–13 ppm). Approximately 12 labeled compounds were detected in the urine, but no unmetabolized methoprene was observed. The distribution and elimination of (14)C in chickens administered methoprene (14)C (isopropyl(2E,4E)-11-methoxy-3,7,11-trimethyl-2,4-dodecadienoate) was investigated. When stomatized chickens were given a single oral dose of approximately 4 mg of methoprene, elimination of (14)C occurred primarily via exhaled air; however, when 105 or 107 mg of methoprene was administered, elimination of (14)C occurred primarily via urinary urine. Up to 19% of (14)C from a single methoprene dose was eliminated from laying hens' eggs within 14 days, and (14)C was detected in all tissues and organs examined. The metabolic pathway of methoprene (isopropyl) was investigated in guinea pigs, steers, and dairy cows for the radiolabeling of (2E,4E)-11-methoxy-3,7,11-trimethyl-2,4-dodecadienoate (Methodepene). Results showed that a significant proportion of the radiolabeled material was absorbed by animal tissues and excreted via respiration. In urine and feces, a small amount of radiolabeled substances are metabolized into free primary metabolites, slightly more are incorporated into simple glucuronides, and a considerable number are present in polar compounds, possibly complex conjugates or polar biochemicals. Methoprene was not detected in urine, but approximately 40% of the radiolabeled substances in feces were derived from unmetabolized methoprene. The formation and metabolism of methoprene conjugates were more extensive in castrated cattle compared to guinea pigs. Treatment of Leghorn chickens with a single oral dose of (5-14C)-methoprene (isopropyl) resulted in residual radioactivity in tissues and eggs. The chemical properties of the residual radiolabeled substances in tissues (muscle, fat, liver), eggs, and excrement were comprehensively studied at multiple doses (0.6 to 77 mg/kg). Although the high initial dose (59 mg/kg) resulted in meprobamate residues in muscle (0.01 ppm), fat (2.13 ppm), and egg yolk (8.03 ppm), these residues accounted for only 39% and 2% of the total 14C labeling in fat and egg yolk, respectively. Radiolabeled natural products resulting from the extensive degradation of meprobamate are the most important 14C residues in tissues and eggs, especially at the low dose of 0.6 mg/kg. 14C cholesterol and normal 14C fatty acids (present as triglycerides) also contribute to the 14C labeling, accounting for 8% and 71% of the total radiolabeling in egg yolk, respectively. Novel minor metabolites of meprobamate were observed in the lipid pool due to the saturation of the dienoate system. These minor metabolites are bound to glycerol and/or cholesterol. Radioactivity was detected in bile, liver, skin, fetus, and mammary glands. In all species, approximately 40% of the radioactivity in feces came from unmetabolized methicillin. Methoprene was not detected in urine. For more complete data on the absorption, distribution, and excretion of methicillin (6 types), please visit the HSDB records page. Metabolites/Metabolites Approximately 4 mg of (14)C methicillin was administered orally to colostomy chickens. The main (14)C product detected was (14)CO2. At high doses, excretion occurred primarily via urine and the intestines. 14C was also found in eggs and in all tissues and organs examined. Metabolites bound to glycerol and/or cholesterol were present, in addition to naturally occurring 14C cholesterol and 14C fatty acid triglycerides. Compounds were found in urine and feces, and each compound underwent significant isomerization. Approximately 19% of 14C was found in eggs. Most of this was associated with egg whites. Radiolabeled fatty acid glycerides and cholesterol were also found in the yolks. Radiolabeled cholesterol and trace amounts of cholesterol esters were found in the blood. Tissue residues were similar to those found in eggs. A Hereford steer was given a single oral dose of 5-(14)C-methoxyprone and slaughtered two weeks later. No primary metabolites were observed in fat, muscle, liver, lungs, blood, or bile. However, most of the tissue radioactivity was present in the form of 14C cholesterol. Radioactivity was detected in approximately 72% of the radioactive cholesterol, bile acids, and deoxycholic acid in the bile. Small amounts of radioactivity were also found in proteins and fatty acid cholesterol esters. When lactating cows were given 5-(14)C-methoxyprone, randomly labeled acetates were produced. These acetates were incorporated into the milk fat, which was then degraded into saturated fatty acids, monounsaturated fatty acids, and dienes. Labeled lactose, whey protein, casein, and free and esterified cholesterol were also observed… Similar qualitative results were observed in the urine of guinea pigs orally administered metoprofen. However, quantitative results differed.
Studies on housefly microsomal enzymes showed that the β-esterases present did not significantly hydrolyze metoprofen, while other analogs were metabolized. Resistant fly strains showed higher microsomal oxidase activity towards juvenile hormone analogs… There was no significant difference in the hydrolysis of branched esters of metoprofen analogs in houseflies. Microsomal esterases. Metoprofen was effective at a concentration of 0.1 μg/pupa, while other drugs were ineffective at a concentration of 10 μg/pupa.
For more complete data on the metabolites/metabolites of metoprofen (15 in total), please visit the HSDB record page.
Biological half-life
Degradation of metoprofen by unidentified pond organisms was studied. In pond water, the half-life is approximately 30 hours at a concentration of 0.001 ppm and approximately 40 hours at a concentration of 0.01 ppm. In wheat, the half-life of methoxyprotein is estimated to be 3 to 7 weeks, depending on the moisture content. The only metabolite observed is free acid.

Toxicity Summary
Identification and Uses: Diflubenzuron is a clear, amber-colored liquid. It is used to control a variety of pests in public health, stored goods (including tobacco), food processing and storage sites, animals, and plants (including greenhouse plants). Specific uses include controlling mosquito larvae; fungus gnats in mushroom houses; tobacco beetles and tobacco moths in stored tobacco; pharaoh ants; leaf miners on greenhouse chrysanthemums; and stored pests in food and tobacco processing plants and warehouses. Human Exposure and Toxicity: No data are currently available. Animal Studies: Non-irritating to skin and eyes (rabbit). In a two-year feeding study, no adverse reactions were observed in rats fed 5000 mg/kg feed and mice fed 2500 mg/kg feed. No teratogenic effects were observed in rats at a dose of 1000 mg/kg and in rabbits at a dose of 500 mg/kg. No mutagenic effects were observed in rats at a dose of 2000 mg/kg. In a three-generation reproductive study with methoprene added to a 2500 mg/kg diet, no adverse effects on the reproductive system of rats were observed. Methoprene at a concentration of 0.2 ppm had no significant effect on the locomotor activity of mosquitofish or goldfish. This concentration was ten times the recommended concentration. Methoprene's interaction with the cell membrane and its perturbation of cellular bioenergetics may be the mechanism by which this compound exerts toxicity on non-target organisms. Methoprene exhibited weak mutagenicity in the Drosophila wing spot assay. Ecotoxicity studies: Xenopus embryos (stage 8) were exposed to the test chemical for 96 hours. The study was conducted under static renewal (24-hour) conditions, and the concentration of the chemical in the water was measured at the beginning and end of the renewal period. Exposure to concentrations up to 2 mg/L of methoprene did not result in developmental toxicity. Administration of amiotoprene increased dopamine levels in the brains of 4-day-old male honeybees.

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Toxicity Data
LC50 (Rat)> 210,000 mg/m3

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Interactions
Exposure to a variety of stressors from natural and anthropogenic sources poses risks to the growth and development of susceptible crustaceans. The application of synthetic pyrethroids and insect growth regulators near shallow coastal waters may produce harmful mixed effects, depending on salinity conditions.This study used a central composite rotatable design combined with multivariate regression analysis to assess the non-additive effects of permethrin (0.01–2 μg/L), methoxyprone (0.03–10 μg/L), and salinity (10–40 ppt) exposure on limb regeneration and molting processes in male and female Uca pugnax. In the experiment, crabs underwent single-limb autotomy followed by molting challenges under 16 different mixed treatment conditions. During the exposure period (21–66 days), the growth of individual limbs, the duration of the major molting phase, aberrant limb regeneration, and respiration were monitored. Six days post-molting, changes in body weight, carapace width, and body condition index were assessed. Carapace tissue was collected, and proteins and chitin were extracted to determine the composition of the newly synthesized exoskeleton. These results indicate that the effects of long-term, low-dose exposure to multiple pesticide stressors on the growth process of U. pugnax are not a simple additive effect. With increasing concentrations of methoxyprone and permethrin, male U. pugnax exhibited higher exoskeleton protein content than females, but lower increases in body weight, carapace width, and body condition. Female U. pugnax also showed a lower increase in carapace width under methoxyprone and permethrin treatment compared to the control group. Furthermore, female U. pugnax exhibited higher respiratory rates at all stages of molting, indicating a higher metabolic rate. In the long term, sexual dimorphism in growth and adaptation may influence the resilience of crustacean populations.

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Non-human toxicity values
Rats oral LD50 >34600 mg/kg
Dogs oral LD50 >5000 mg/kg
Rabbit dermal LD50 3500 mg/kg
LD50 non-toxic to adult bees (oral and topical) >1000 ug/l/bee
For more complete non-human toxicity data on methoxyproteins (7 types), please visit the HSDB record page.

[1]. Olmstead AW, LeBlanc GL. Low exposure concentration effects of methoprene on endocrine-regulated processes in the crustacean Daphnia magna. Toxicol Sci. 2001;62(2):268-273.

[2]. Toxicity of methoprene as assessed by the use of a model microorganism. Toxicol In Vitro. 2005;19(7):951-956.

Therapeutic Uses
This study investigated the effects of the juvenile hormone analogue (JHA) metoprone on T. koraiensis hemorrhagic flagellates (Tulahuen strain, Tul 2). In vitro experiments showed that 150 μM metoprone induced cell death in T. koraiensis. Conversely, in vivo experiments showed that metoprone did not eliminate hemorrhagic flagellates, but a decrease in parasitemia levels was observed in infected mice after treatment with a dose of 200 μg/mouse/day for 5 consecutive days. Based on these results and the low toxicity of metoprone, we believe this compound could serve as an effective blood disinfectant for transfusions. Therapeutic Uses
Drug treatment for African trypanosomiasis (sleeping sickness) is limited by toxicity and drug resistance; only one new drug has been introduced for the treatment of this disease in humans in the past 50 years. We report that the juvenile hormone analogue metoprone and several structurally related isoprene compounds can kill T. koraiensis in vitro. Among other isoprene compounds tested, juvenile hormone III and mammalian retinol X receptor ligands were the most potent trypanosome killers. These compounds killed both procyclic and hematogenous trypanosomes, with LD50 values of 5–30 μM. Of the two stereoisomers of meproximalne, the EE form exhibited the highest activity, suggesting a possible protein target involved in mediating the effects of these analogs on the parasite. However, meproximalne failed to clear trypanosomes from the blood of infected mice. Meproximalne's direct downstream metabolite, meproximalonic acid, was not an effective antitrypanosome drug, indicating that meproximalne is converted into an inactive compound in mice. Given the low toxicity of meproximalne and its analogs in mammals and their well-characterized nature, these studies highlight the importance of further exploring these isoprene compounds as lead compounds for the treatment of African trypanosomiasis.

C19H34O3

310.478

310.25

40596-69-8

S-Methoprene;65733-16-6;Methoprene-d7;2673270-24-9

5366546

Colorless to light yellow liquid

0.9±0.1 g/cm3

385.7±25.0 °C at 760 mmHg

164ºC

162.4±17.8 °C

0.0±0.9 mmHg at 25°C

1.462

5.63

0

3

11

22

378

0

CC(OC(/C=C(/C=C/CC(CCCC(OC)(C)C)C)\C)=O)C

NFGXHKASABOEEW-LDRANXPESA-N

InChI=1S/C19H34O3/c1-15(2)22-18(20)14-17(4)11-8-10-16(3)12-9-13-19(5,6)21-7/h8,11,14-16H,9-10,12-13H2,1-7H3/b11-8+,17-14+

propan-2-yl (2E,4E)-11-methoxy-3,7,11-trimethyldodeca-2,4-dienoate

ZPA-1019; ZPA 1019; Methoprene

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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

Ethanol : ~100 mg/mL (~322.09 mM)
Acetone :≥ 50 mg/mL (~161.05 mM)
DMSO : ~25 mg/mL (~80.52 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (8.05 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 2.5 mg/mL (8.05 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (8.05 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 4: ≥ 2.5 mg/mL (8.05 mM) (saturation unknown) in 10% EtOH + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear EtOH stock solution to 400 μL of PEG300 and mix evenly; then add 50 μL of Tween-80 to the above solution and mix evenly; then add 450 μL of normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 5: ≥ 2.5 mg/mL (8.05 mM) (saturation unknown) in 10% EtOH + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear EtOH stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

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Solubility in Formulation 6: ≥ 2.5 mg/mL (8.05 mM) (saturation unknown) in 10% EtOH + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear EtOH stock solution to 900 μL of corn oil and mix evenly.

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