Phosphamidon [N,N-diethyl 1-Chloro-2-dimethy1phosphate-prop-2-enamide ] 
The comparative fate of the cis and trans isomers of phosphamidon 
was studied. The biological half-lives of the two isomers were very short 
in plants and animals and of comparable duration. Both isomers were con- 
verted to similar oxidative and hydrolytic metabolites. The rates of 
formation were different. Overall decomposition proceeded at almost 
equivalent rates (202). 
After intraperitoneal injection of cis or trans phosphamidon-P 32 in 
male white rats, excreta was collected during a 4-day period. About 60% 
of the dose--either isomer--was recovered within 24 hours after injection, 
most from urine. The hydrolytic products were almost entirely dimethyl 
phosphate, with small amounts of phosphoric acid and O-demethyl phosphamidon 
(202). 
Phosphamidon was orally administered to white rats and a femal goat. 
In addition to hydrolysis products, nine metabolites were isolated from urine 
but only four were characterized: desethyl phosphamidon, deschlorophosphami- 
don amide, O%-chloro-N,N-diethylacetoacetamide and an unsubstituted amide. Of 
these, only the desethyl metabolite was not found in milk (283). 
Studies with labeled phosphamidon showed that plants metabolized 
phosphamidon to desethylphosphamidon, dimethyl phosphate, o-chloro- 
acetoacetate diethyl amide and o-chloroacetoacetate ethylamide (29, 720, 
985). After foliar treatment of cotton, phosphamidon, O-demethyl phos- 
phamidon, N-desethyl phosphamidon, hydroxyethyl phosphamidon, and dimethyl 
phosphate were detected externally. Internally, orthophosphate and an un- 
known were observed in addition to the foregoing compounds (202). 
In fifth-instar tobacco budworms and bollworms, metabolism of the 
two isomers was similar. After injection of labeled phosphamidon, compounds 
I, II, IfI, IV, X, phosphamidon acid (VII), dimethyl phosphate (VIII), methyl 
phosphate (IX), and an unknown were observed in internal extracts. In the 
excreta, compounds I, II, III, IV, VII, VIII, and X were detected (202). 
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