ContaminantDB: Phenmedipham

Identification Taxonomy Biological Properties Physical Properties Toxicity Profile Spectra Concentrations Links References Targets (5)XML

Record Information

Version

1.0

Creation Date

2009-06-17 23:53:05 UTC

Update Date

2026-03-26 19:48:56 UTC

Accession Number

CHEM000854

Identification

Common Name

Phenmedipham

Class

Small Molecule

Description

Phenmedipham is a selective herbicide of the carbanilate and biscarbamate classes. Carbamate pesticides are derived from carbamic acid and kill insects in a similar fashion as organophosphate insecticides. They are widely used in homes, gardens and agriculture. The first carbamate, carbaryl, was introduced in 1956 and more of it has been used throughout the world than all other carbamates combined. Because of carbaryl's relatively low mammalian oral and dermal toxicity and broad control spectrum, it has had wide use in lawn and garden settings. Most of the carbamates are extremely toxic to Hymenoptera, and precautions must be taken to avoid exposure to foraging bees or parasitic wasps. Some of the carbamates are translocated within plants, making them an effective systemic treatment. Phenmedipham was developed by Schering AG and approved for use in the United States in 1970. Today, about 100 tons of Phenmedipham are used each year. It is commonly used in beet, spinach, and strawberry crops to protect against weeds, often in comination with Desmedipham under the trade names Betanal or Betamax. (3)

Contaminant Sources

HPV EPA Chemicals
STOFF IDENT Compounds
T3DB toxins
ToxCast & Tox21 Chemicals

Contaminant Type

Amine
Carbamate
Ester
Ether
Herbicide
Organic Compound
Pesticide
Synthetic Compound

Chemical Structure

MOL SDF PDB SMILES InChI

Synonyms

Value	Source
3-(Methoxyformamido)phenyl (3-methylphenyl)carbamate	ChEBI
3-[(Methoxycarbonyl)amino]phenyl (3-methylphenyl)carbamate	ChEBI
3-Methoxycarbonyl-N-(3'-methylphenyl)-carbamate	ChEBI
Methyl 3-(3-methylcarbaniloyloxy)carbanilate	ChEBI
3-(Methoxyformamido)phenyl (3-methylphenyl)carbamic acid	Generator
3-[(Methoxycarbonyl)amino]phenyl (3-methylphenyl)carbamic acid	Generator
3-Methoxycarbonyl-N-(3'-methylphenyl)-carbamic acid	Generator
Methyl 3-(3-methylcarbaniloyloxy)carbanilic acid	Generator
Betanal	MeSH
Fenmedifam	MeSH

Chemical Formula

C₁₆H₁₆N₂O₄

Average Molecular Mass

300.309 g/mol

Monoisotopic Mass

300.111 g/mol

CAS Registry Number

13684-63-4

IUPAC Name

1-3-{[hydroxy(methoxy)methylidene]amino}phenoxy-N-(3-methylphenyl)methanimidic acid

Traditional Name

1-3-{[hydroxy(methoxy)methylidene]amino}phenoxy-N-(3-methylphenyl)methanimidic acid

SMILES

COC(O)=NC1=CC(OC(O)=NC2=CC=CC(C)=C2)=CC=C1

InChI Identifier

InChI=1S/C16H16N2O4/c1-11-5-3-6-12(9-11)18-16(20)22-14-8-4-7-13(10-14)17-15(19)21-2/h3-10H,1-2H3,(H,17,19)(H,18,20)

InChI Key

IDOWTHOLJBTAFI-UHFFFAOYSA-N

Chemical Taxonomy

Description

belongs to the class of organic compounds known as phenylcarbamic acid esters. These are ester derivatives of phenylcarbamic acids.

Kingdom

Organic compounds

Super Class

Benzenoids

Class

Benzene and substituted derivatives

Sub Class

Phenylcarbamic acid esters

Direct Parent

Phenylcarbamic acid esters

Alternative Parents

Substituents

Phenylcarbamic acid ester
Phenoxy compound
Toluene
Carbamic acid ester
Carbonic acid derivative
Organic nitrogen compound
Organic oxygen compound
Organopnictogen compound
Organic oxide
Hydrocarbon derivative
Organooxygen compound
Organonitrogen compound
Carbonyl group
Aromatic homomonocyclic compound

Molecular Framework

Aromatic homomonocyclic compounds

External Descriptors

carbamate ester (CHEBI:81734 )
Carbanilate herbicides (C18420 )

Biological Properties

Status

Detected and Not Quantified

Origin

Exogenous

Cellular Locations

Membrane

Biofluid Locations

Not Available

Tissue Locations

Not Available

Pathways

Name	SMPDB Link	KEGG Link
Metabolic Pathways	Not Available	Not Available

Applications

Not Available

Biological Roles

Not Available

Chemical Roles

Not Available

Physical Properties

State

Solid

Appearance

Colorless and odorless powder.

Experimental Properties

Property	Value
Melting Point	143-144 °C
Boiling Point	Decomposition at> 200 °C
Solubility	Practically insoluble in water (4.7 mg/L); soluble in polar organic solvents

Predicted Properties

Property	Value	Source
Water Solubility	0.017 g/L	ALOGPS
logP	2.5	ALOGPS
logP	5.28	ChemAxon
logS	-4.2	ALOGPS
pKa (Strongest Acidic)	2.91	ChemAxon
pKa (Strongest Basic)	-2.7	ChemAxon
Physiological Charge	0	ChemAxon
Hydrogen Acceptor Count	6	ChemAxon
Hydrogen Donor Count	2	ChemAxon
Polar Surface Area	83.64 Å²	ChemAxon
Rotatable Bond Count	5	ChemAxon
Refractivity	85.63 m³·mol⁻¹	ChemAxon
Polarizability	30.77 Å³	ChemAxon
Number of Rings	2	ChemAxon
Bioavailability	1	ChemAxon
Rule of Five	No	ChemAxon
Ghose Filter	Yes	ChemAxon
Veber's Rule	No	ChemAxon
MDDR-like Rule	No	ChemAxon

Spectra

Spectrum Type	Description	Splash Key	View
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positive	splash10-0a4i-0910000000-f30d7fef5d59b6c5ce93	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TMS_1_1) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TMS_1_2) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TMS_2_1) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TBDMS_1_1) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TBDMS_1_2) - 70eV, Positive	Not Available	Spectrum
Predicted GC-MS	Predicted GC-MS Spectrum - GC-MS (TBDMS_2_1) - 70eV, Positive	Not Available	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 30V, Positive	splash10-000i-0900000000-00031c14ca44e9139da9	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 15V, Positive	splash10-014r-0900000000-58c2bf322552cc023a2c	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 30V, Positive	splash10-000i-0900000000-48fd93926a23be06e22f	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 40V, Positive	splash10-000i-0900000000-e0ddaebfe93fd113eec8	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 20V, Positive	splash10-000i-0900000000-ec1e788887825ffd4f0c	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 10V, Positive	splash10-014i-0900000000-f503ecc696af8c003a6e	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 50V, Positive	splash10-000i-0900000000-73e4c8828d11574f5451	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 35V, Positive	splash10-014i-0900000000-285f09d3c2697ef6975a	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 75V, Positive	splash10-052r-3900000000-1c4f4f8b000368ac97de	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 90V, Positive	splash10-06el-8900000000-89453a33a33ec2ad9279	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 60V, Positive	splash10-000i-1900000000-6a34a96bdb4b2086cd06	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 45V, Positive	splash10-000i-0900000000-0fbfef39b582949ab789	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 35V, Positive	splash10-014i-0900000000-aba50b6e242108613201	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 45V, Positive	splash10-000i-0900000000-6c56388e0bc4b72f9781	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 30V, Positive	splash10-000i-0900000000-9f94251a5005a58d3751	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 60V, Positive	splash10-000i-1900000000-308e1ba29a7937090320	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 15V, Positive	splash10-014r-0900000000-1a043edb4709fa7aad1d	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 75V, Positive	splash10-052r-3900000000-dcc4c2258728e16c13a9	Spectrum
LC-MS/MS	LC-MS/MS Spectrum - 90V, Positive	splash10-06el-8900000000-1ec41aa995a5fb8c1e67	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Positive	splash10-0gb9-0915000000-63d6e03ed88c54642817	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Positive	splash10-014i-0910000000-29a9b44697d8a365aa4a	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Positive	splash10-00m0-2900000000-9af527c638cac566c742	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 10V, Negative	splash10-00lr-0960000000-7f9c2c8524e4108413e5	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 20V, Negative	splash10-00lr-0930000000-35b7fc9406bb7cece661	Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum - 40V, Negative	splash10-001i-0900000000-b8bb1126db209fc546e1	Spectrum
MS	Mass Spectrum (Electron Ionization)	splash10-00lr-5900000000-18214c4b9332b3821a3e	Spectrum

Toxicity Profile

Route of Exposure

Inhalation (2) ; oral (2); dermal (2)

Mechanism of Toxicity

Phenmedipham is a cholinesterase or acetylcholinesterase (AChE) inhibitor. Carbamates form unstable complexes with chlolinesterases by carbamoylation of the active sites of the enzymes. This inhibition is reversible. A cholinesterase inhibitor suppresses the action of acetylcholine esterase. Because of its essential function, chemicals that interfere with the action of acetylcholine esterase are potent neurotoxins, causing excessive salivation and eye-watering in low doses. Headache, salivation, nausea, vomiting, abdominal pain and diarrhea are often prominent at higher levels of exposure. Acetylcholine esterase breaks down the neurotransmitter acetylcholine, which is released at nerve and muscle junctions, in order to allow the muscle or organ to relax. The result of acetylcholine esterase inhibition is that acetylcholine builds up and continues to act so that any nerve impulses are continually transmitted and muscle contractions do not stop.

Metabolism

The carbamates are hydrolyzed enzymatically by the liver; degradation products are excreted by the kidneys and the liver. (2)

Toxicity Values

LD50: >8000 mg/kg (Rat, oral)

Lethal Dose

Not Available

Carcinogenicity (IARC Classification)

No indication of carcinogenicity to humans (not listed by IARC).

Uses/Sources

Phenmedipham is a selective herbicide commonly used in beet, spinach, and strawberry crops to protect against weeds, often in comination with Desmedipham.

Minimum Risk Level

Not Available

Health Effects

Acute exposure to cholinesterase inhibitors can cause a cholinergic crisis characterized by severe nausea/vomiting, salivation, sweating, bradycardia, hypotension, collapse, and convulsions. Increasing muscle weakness is a possibility and may result in death if respiratory muscles are involved. Accumulation of ACh at motor nerves causes overstimulation of nicotinic expression at the neuromuscular junction. When this occurs symptoms such as muscle weakness, fatigue, muscle cramps, fasciculation, and paralysis can be seen. When there is an accumulation of ACh at autonomic ganglia this causes overstimulation of nicotinic expression in the sympathetic system. Symptoms associated with this are hypertension, and hypoglycemia. Overstimulation of nicotinic acetylcholine receptors in the central nervous system, due to accumulation of ACh, results in anxiety, headache, convulsions, ataxia, depression of respiration and circulation, tremor, general weakness, and potentially coma. When there is expression of muscarinic overstimulation due to excess acetylcholine at muscarinic acetylcholine receptors symptoms of visual disturbances, tightness in chest, wheezing due to bronchoconstriction, increased bronchial secretions, increased salivation, lacrimation, sweating, peristalsis, and urination can occur. Chronically high (>10 years) exposure leads to neuropsychological consequences including disturbances in perception and visuo-motor processing. (1)

Symptoms

As with organophosphates, the signs and symptoms are based on excessive cholinergic stimulation. Unlike organophosphate poisoning, carbamate poisonings tend to be of shorter duration because the inhibition of nervous tissue acetylcholinesterase is reversible, and carbamates are more rapidly metabolized. Muscle weakness, dizziness, sweating and slight body discomfort are commonly reported early symptoms. Headache, salivation, nausea, vomiting, abdominal pain and diarrhea are often prominent at higher levels of exposure. Contraction of the pupils with blurred vision, incoordination, muscle twitching and slurred speech have been reported. (3)

Treatment

If the compound has been ingested, rapid gastric lavage should be performed using 5% sodium bicarbonate. For skin contact, the skin should be washed with soap and water. If the compound has entered the eyes, they should be washed with large quantities of isotonic saline or water. In serious cases, atropine and/or pralidoxime should be administered. Anti-cholinergic drugs work to counteract the effects of excess acetylcholine and reactivate AChE. Atropine can be used as an antidote in conjunction with pralidoxime or other pyridinium oximes (such as trimedoxime or obidoxime), though the use of '-oximes' has been found to be of no benefit, or possibly harmful, in at least two meta-analyses. Atropine is a muscarinic antagonist, and thus blocks the action of acetylcholine peripherally.

Concentrations

Not Available

External Links

DrugBank ID

Not Available

HMDB ID

HMDB0256405

FooDB ID

Not Available

Phenol Explorer ID

Not Available

KNApSAcK ID