Pyrimethanil is a fungicide classified as anilinopyrimidines, specifically a strobilurin. After being exposed to two environmentally relevant concentrations of pyrimethanil for an extended period of time, the Italian tree frog H. intermedia's tissues may undergo histological changes and exhibit a variety of toxic reactions (5 and 50 µg/L)[2]. In the medium of three-day-old cultures, pyrimethanil reduces the activity of polygalacturonase, cellulase, proteinase, and laccase. For polygalacturonase, cellulase, and proteinase, the 50% reduction in total enzyme activity (IC50) caused by pyrimethanil is roughly 0.25 μM, and for laccase, it is approximately 1.0 μM[3].

Absorption, Distribution and Excretion
In the rat, rapidly absorbed, metabolized and excreted. Following single oral dose, > 95% excreted within 6-8 hours.

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Metabolism / Metabolites
Metabolism involves oxidation to hydroxylated derivatives followed by conjugation. ... Little metabolism occurs on fruit.

[1]. Petr Masner, et al. Possible methionine biosynthesis inhibition by pyrimidinamine fungicides. Pesticide Science
[2]. L Kanetis, et al. Characterization of genetic and biochemical mechanisms of fludioxonil and pyrimethanil resistance in field isolates of Penicillium digitatum. Phytopathology
[3]. Richard J. Milling, et al. Mode of action of the anilino‐pyrimidine fungicide pyrimethanil. 2. Effects on enzyme secretion in Botrytis cinerea. Volume45, Issue1, September 1995.
[4]. Salvatore D'Aquino, et al. Residue levels and effectiveness of pyrimethanil vs imazalil when using heated postharvest dip treatments for control of Penicillium decay on citrus fruit. J Agric Food Chem. 2006 Jun 28;54(13):4721-6.

Pyrimethanil is a member of the class of aminopyrimidines that is N-phenylpyrimidin-2-amine carrying two additional methyl substituents at positions 4 and 6. A fungicide used to control grey mould on fruit, vegetables and ornamentals as well as leaf scab on pome fruit. Also commonly employed to control Botrytis cinerea throughout the winemaking process in grapes, must, fermenting must and wine. It has a role as an aryl hydrocarbon receptor agonist, an environmental contaminant, a xenobiotic and an antifungal agrochemical. It is an aminopyrimidine, a secondary amino compound and an anilinopyrimidine fungicide.
Pyrimethanil has been reported in Ganoderma lucidum with data available.
Pyrimethanil is a fungicide used on grape vines.
See also: Cyprodinil (annotation moved to).

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Mechanism of Action
/Its mode of action is/ inhibition of the secretion of fungal enzymes relevant for pathogenicity.
The effect of pyrimethanil on the levels of cell wall degrading enzymes secreted by Botrytis cinerea Pers. was investigated in diseased plant tissues and in liquid B. cinerea cultures. Total proteinase activity isolated from infected carrot slices which were treated with 5.0 uM pyrimethanil was decreased by 76%, 3 d after inoculation. Polygalacturonase, cellulase, proteinase and laccase activities were all decreased in the medium of three day-old cultures grown in the presence of pyrimethanil. The pyrimethanil concentrations resulting in 50% reduction in total enzyme activities (IC50) were approximately 0.25 uM for polygalacturonase, cellulase and proteinase, and approximately 1.0 uM for laccase. No significant growth inhibition was observed at these pyrimethanil concentrations. Pyrimethanil did not inhibit the enzymes directly, nor did it inhibit the synthesis of cytosolic proteins. Therefore, it was proposed that the fungicide inhibits protein secretion at a post-translational stage in the secretory pathway. Large differences were found in the effects of pyrimethanil on the growth of B. cinerea in liquid cultures and on agar plates, depending on the composition of the medium. In liquid media containing cellulose and protein as carbon and nitrogen sources, growth inhibition occurred at 5.0 uM pyrimethanil, whilst no growth inhibition was observed with 50 uM pyrimethanil in malt extract. Similarly, growth occurred on potato/dextrose agar (PDA) at 0.5 uM pyrimethanil, but no growth was seen at this concentration on agars containing cellulose and protein. Thus it appears that pyrimethanil is most active in media where the fungus has to utilise extracellular enzymes to mobilise the nutrients it requires for growth.

C12H13N3

199.25

199.11

53112-28-0

Pyrimethanil-13C,15N2;Pyrimethanil-d5;2118244-83-8

91650

Colorless crystals

1.1±0.1 g/cm3

362.8±45.0 °C at 760 mmHg

96°C

173.2±28.7 °C

0.0±0.8 mmHg at 25°C

1.622

2.84

1

3

2

15

179

0

N([H])(C1C([H])=C([H])C([H])=C([H])C=1[H])C1=NC(C([H])([H])[H])=C([H])C(C([H])([H])[H])=N1

ZLIBICFPKPWGIZ-UHFFFAOYSA-N

InChI=1S/C12H13N3/c1-9-8-10(2)14-12(13-9)15-11-6-4-3-5-7-11/h3-8H,1-2H3,(H,13,14,15)

4,6-dimethyl-N-phenylpyrimidin-2-amine

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 : 130 mg/mL (652.45 mM)

Solubility in Formulation 1: ≥ 3.25 mg/mL (16.31 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 32.5 mg/mL clear DMSO 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 2: 3.25 mg/mL (16.31 mM) 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 32.5 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: ≥ 3.25 mg/mL (16.31 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 32.5 mg/mL clear DMSO 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.)