Dipterex (Bayer L 13/59) (0,0-Dimethyl-2,2,2-trichloro-1-hydroxyethyl 
phosphonate) 

p32. 1abeled dipterex was administered intravenously to a cow. 
Analysis of blood indicated a rapid hydrolysis. Trichloroethanol 
glucuronic acid was isolated and identified (Robbins et al., 1956; Arthur 
and Casida, 1957) from urine samples. Enzyme studies also indicated 
cleavage of dipterex to form dimethyl phosphate. Other studies have 
shown that dipterex spontaneously transforms into DDVP at pH 5.0 and 
greater (Metcalf, 1959; Miyamato, 1959). 
In rat brain homogenates, c14-1abeled dipterex was rapidly metaboliz- 
ed to monodemethylated dipterex, monomethylphosphate, 2,2,2-trichloro- 
l-hydroxyethyl phosphonic acid, and a fourth unidentified compound 
(Hassan et al., 1965a). Following injection in rats of dipterex labeled 
in the two methyl groups, 60% of the els, was recovered after 24 hours 
in the expired air and urine. cl4o, and C!4-formate constituted about 
50% of the recovered radioactivity (Hassan and Zayed, 1965). Additional 
studies were conducted with P22-labeled dipterex. After interperitoneal 
injection, 75-85% of the administered radioactivity appeared in the urine 
within 48 hours. Three P?-labeled compounds were found in the urine. 
Two were identified as mono- and dimethylphosphates. The third metabolite 
was not identified (Hassan et al., 1965c). 
After exposure of larvae of the cotton leaf worm (Prodenia lituria F.) 
to labeled dipterex, O-methyl-2,2,2-trichloro-l-hydroxyethyl phosphonic 
acid, 2,2,2-trichloro-l-hydroxyethyl phosphonic glucuronic acid (65-75%), 
mono- and dimethylphosphate, and cl40, (Zayed and Hassan, 1965a; Hassan et al, 
1965b) were found. 
98 
