The Free Dictionary  
mailing list For webmasters
Welcome Guest Forum Search | Active Topics | Members

Sarin Options
Daemon
Posted: Saturday, October 28, 2017 12:00:00 AM
Rank: Advanced Member

Joined: 3/7/2009
Posts: 22,046
Neurons: 66,141
Location: Inside Farlex computers
Sarin

Sarin is a colorless and odorless nerve agent estimated to be more than 500 times as toxic as cyanide. A cholinesterase inhibitor, it effectively causes nerve impulses to be continually transmitted, resulting in a loss of control of bodily functions, suffocation, and death. Discovered in 1938 by German scientists attempting to create stronger pesticides, sarin was mass produced by the German military during World War II. Did the Nazis use sarin against Allied targets? More...
KSPavan
Posted: Sunday, October 29, 2017 3:37:10 AM

Rank: Advanced Member

Joined: 1/28/2015
Posts: 2,020
Neurons: 1,980,707
Location: Kolkata, Bengal, India
Article of the Day
Sarin
Sarin is a colorless and odorless nerve agent estimated to be more than 500 times as toxic as cyanide. A cholinesterase inhibitor, it effectively causes nerve impulses to be continually transmitted, resulting in a loss of control of bodily functions, suffocation, and death. Discovered in 1938 by German scientists attempting to create stronger pesticides, sarin was mass produced by the German military during World War II.
raghd muhi al-deen
Posted: Sunday, October 29, 2017 10:15:06 AM

Rank: Advanced Member

Joined: 4/19/2017
Posts: 775
Neurons: 69,561
Location: Baghdad, Mayorality of Baghdad, Iraq
Sarin
Also found in: Dictionary, Thesaurus, Medical, Financial, Acronyms, Encyclopedia.
Sarin
Sarin[1]
Preferred IUPAC name

(RS)-Propan-2-yl methylphosphonofluoridate
Other names

(RS)-O-Isopropyl methylphosphonofluoridate; IMPF;
GB;[2]
2-(Fluoro-methylphosphoryl)oxypropane;
Phosphonofluoridic acid, P-methyl-, 1-methylethyl ester
Identifiers
CAS number 107-44-8 Yes
PubChem 7871
ChemSpider 7583 Yes
UNII B4XG72QGFM
ChEMBL CHEMBL509554 Yes
Jmol-3D images Image 1
SMILES

FP(=O)(OC(C)C)C

InChI

InChI=1S/C4H10FO2P/c1-4(2)7-8(3,5)6/h4H,1-3H3 Yes
Key: DYAHQFWOVKZOOW-UHFFFAOYSA-N Yes

InChI=1/C4H10FO2P/c1-4(2)7-8(3,5)6/h4H,1-3H3

InChI=1/C4H10FO2P/c1-4(2)7-8(3,5)6/h4H,1-3H3
Key: DYAHQFWOVKZOOW-UHFFFAOYAY

Properties
Molecular formula C4H10FO2P
Molar mass 140.09 g mol−1
Appearance Clear colorless liquid
Odor Odorless in pure form
Density 1.0887 g/cm³ (25 °C)
1.102 g/cm³ (20 °C)
Melting point

-56 °C, 217 K, -69 °F
Boiling point

158 °C, 431 K, 316 °F
Solubility in water Miscible
Hazards
MSDS Lethal Nerve Agent Sarin (GB)
EU classification Extremely Toxic (T+)[3]
Main hazards It is a lethal cholinergic agent.
NFPA 704
NFPA 704.svg
1
4
0
LD50 70 mg-min/m3
(verify) (what is: Yes/?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Sarin, or GB, is an organophosphorus compound with the formula [(CH3)2CHO]CH3P(O)F. It is a colorless, odorless liquid,[4] used as a chemical weapon owing to its extreme potency as a nerve agent. It has been classified as a weapon of mass destruction in UN Resolution 687. Production and stockpiling of sarin was outlawed by the Chemical Weapons Convention of 1993 where it is classified as a Schedule 1 substance.
Production and structure

Sarin is a chiral molecule (typically racemic), with four substituents attached to the tetrahedral phosphorus center.[5] The SP form (the RP form is shown) is the more active enantiomer due to its greater binding to acetylcholinesterase.[6] It is prepared from methylphosphonyl difluoride and a mixture of isopropyl alcohol and isopropylamine.

CH3P(O)F2 + (CH3)2CHOH → [(CH3)2CHO]CH3P(O)F + HF

Isopropylamine is added to neutralize the hydrogen fluoride generated during this alcoholysis reaction. As a binary chemical weapon, it can be generated in situ by this same reaction.
Biological effects

Its mechanism of action resembles that of some commonly used insecticides, such as malathion. In terms of biological activity, it resembles carbamate insecticides such as Sevin and medicines pyridostigmine, neostigmine, and physostigmine. Like other nerve agents, sarin attacks the nervous system.

Specifically, sarin is a potent inhibitor of the enzyme acetylcholinesterase,[7] a protein that degrades the neurotransmitter acetylcholine after it is released into the synaptic cleft. In vertebrates, acetylcholine is the neurotransmitter used at the neuromuscular junction, where signals are transmitted between neurons from the central nervous systems to muscle fibres. Normally, acetylcholine is released from the neuron to stimulate the muscle, after which it is degraded by acetylcholinesterase, allowing the muscle to relax. A build-up of acetylcholine in the synaptic cleft, due to the inhibition of cholinesterase, means the neurotransmitter continues to act on the muscle fibre, so that any nerve impulses are effectively continually transmitted. Death will usually occur as a result of asphyxia due to the inability of the muscles involved in breathing to function.

Sarin acts on cholinesterase by forming a covalent bond with the particular serine residue at the active site. Fluoride is the leaving group, and the resulting phosphoester is robust and biologically inactive.[8][9]
Degradation and shelf life
Rabbit used to check for leaks at sarin production plant, Rocky Mountain Arsenal (1970)

The most important chemical reactions of phosphoryl halides is the hydrolysis of the bond between phosphorus and the fluoride. This P-F bond is easily broken by nucleophilic agents, such as water and hydroxide. At high pH, sarin decomposes rapidly to nontoxic phosphonic acid derivatives.[10][11]

Sarin degrades after a period of several weeks to several months. The shelf life can be shortened by impurities in precursor materials. According to the CIA, some Iraqi sarin had a shelf life of only a few weeks, owing mostly to impure precursors.[12]

Its otherwise short shelf life can be extended by increasing the purity of the precursor and intermediates and incorporating stabilizers such as tributylamine. In some formulations, tributylamine is replaced by diisopropylcarbodiimide (DIC), allowing sarin to be stored in aluminium casings. In binary chemical weapons, the two precursors are stored separately in the same shell and mixed to form the agent immediately before or when the shell is in flight. This approach has the dual benefit of solving the stability issue and increasing the safety of sarin munitions.
Effects and treatment

with my pleasure
Users browsing this topic
Guest


Forum Jump
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.

Main Forum RSS : RSS
Forum Terms and Guidelines. Copyright © 2008-2017 Farlex, Inc. All rights reserved.