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Pyraclofos

Pyraclofos structure

CAS No:
77458-01-6
Formula:
C14H18ClN2O3PS
Chemical Name:
Pyraclofos
Synonyms:
(rs)-(o-1-(4-chlorophenyl)pyrazol-4-yl-o-ethyl-s-propylphosphorothioate);phosphorothioicacid,o-(1-(4-chlorophenyl)-1h-pyrazol-4-yl)o-ethyls-propyle;VOLTAGE;VOLTAGE(R);PYRACLOFOS, 50MG, NEAT;pyraclofos (bsi,draft e-iso,draft f-iso);（RS）-O-ethyl-S-propyl-O-[1-(4-chlorophenyl) pyrazol-4-yl] phosphorothioate;OMS3034
Categories:
Agrochemicals > Insecticides

Description

ChEBI: Pyraclofos is an organic thiophosphate, an organothiophosphate insecticide, an organochlorine insecticide, a member of pyrazoles, a member of monochlorobenzenes and an organosulfur compound. It has a role as an EC 3.1.1.7 (acetylcholinesterase) inhibitor and an agrochemical.

Pyraclofos Basic Attributes

Molecular Weight：

360.8

Exact Mass：

360.80

HScode：

29331990

Characteristics

PSA：

78.6

XLogP3：

5.19230

Density：

1.27

Melting Point：

25°C

Boiling Point：

164approximate 164℃(0.013hPa)

Refractive Index：

1.595

Water Solubility：

Storage Conditions：

0-6°C

Vapor Pressure：

1.6×10-6Pa (20 °C)

Toxicity：

The acute oral LD50for rats is 237 mg/kg. The inhalation LC50 for rats is 1.69 mg/L air. NOEL (2 yr) for rats is 0.10–0.12 mg/kg diet (0.005–0.006 mg/kg/d). Pyraclofos administered to rats is rapidly degraded, and more than 90% of the dose is excreted principally in the urine within 24 h. The degradation routes are cleavages of the PS, PO-alkyl, and PO-aryl bonds in both animals and plants.

Henrys Law Constant：

2.3×104mol/(m3Pa) at 25℃, Ebert et al. (2023)

Critical Temperature & Pressure：

0-6°C

Safety Information

Packing level：

III

Hazard category：

6.1(b)

Transport codes：

3018

hazard class code：

Xi,Xn

RTECS Number：

TE8346000

Marks：

Xi,Xn

Precautionary statement(s)：

P260, P261, P264, P270, P271, P273, P301+P310, P304+P312, P304+P340, P307+P311, P312, P321, P330, P391, P405, P501

Hazard Statements：

RIDADR：

3018

Pyraclofos Use and Manufacturing

Methods of Manufacturing

Preparation of 1-(4-chlorophenyl)-4-hydroxypyrazole. 3-Chloroacetone aldehyde hydrazone-p-chlorobenzene undergoes cyclization reaction in methanol in the presence of sodium hydroxide to produce 1-(4-chloro Phenyl)-4-hydroxypyrazole. Synthesis of pyrazophos 1-(4-chlorophenyl)-4-hydroxypyrazole in the presence of triethylamine, in acetonitrile solution, reacts with O-ethyl-S-propylthiophosphoryl chloride The temperature is 50°C, and the reaction time is 3 hours to prepare pyrazophos.

Uses

This product has poor anti-acetylcholinease activity in vitro, but it has good insecticidal activity against Spodoptera litura, and its larval acetylcholinesterase is inhibited by this product. This product shows a higher inhibitory activity on insect fatty esterases (compared to acetylcholinesterase in the nervous system). With contact and stomach toxicity, no systemic activity on the root system. It is effective against a variety of pests such as Lepidoptera, Coleoptera, aphids, Diptera and cockroaches, as well as spider mites, root mites, rickets, ticks and nematodes. Field tests showed that the control objects also include cotton bollworm, red bollworm, coastal armyworm, cotton planthopper, tobacco thrips, potato beetle, potato tuber moth, tea leaf moth, tea yellow thrips, alfalfa leaf weevil, tobacco hawk moth. The dosage is 0.5～1.5kg (active ingredient)/hm2. It has slight phytotoxicity to apple, citrus, Japanese pear and other fruit trees, which varies with the varieties.

Pyraclofos is used to control Lepidoptera, Coleoptera, mites and nematodes in fruit, vegetables, ornamentals and forestry. It has also been used in a human health application to control filarial worms.

Material

Triethylamine