Dimetilan (2-Dimethylcarbamoyl -3-methyl-5-pyrazolyl dimethylcarbamate) 
Dimetilan had a half-life in houseflies (Musca domestica L.), the 
American cockroach (Periplaneta americana L.), and the Geman cockroach 
(Blatella germanica L.) of less than 0.5 hours. Hydrolysis of the 
carbamate ester group accounted for some metabolism, since 13% of the 
injected dose was liberated as cl4o, within 1 hour after injection of 
dimetilan. Nine metabolites were detected from the German cockroach; 
6 from the American cockroach; and 4 from the housefly. Chromatography 
indicated that the metabolite formed first and the major product was 
probably 2-dimethylcarbamoyl -3-methyl-5-pyrazolyl N-hydroxymethyl, N- 
methylcarbamate. This could serve as a precursor for 2-(N-hydroxymethyl, 
N-methyl) carbamoyl-3-methyl-5-pyrazolyl N-hydroxymethyl, N-methylcar- 
bamate, thought to be the structure of another of the metabolites found 
in both cockroaches but not in the housefly. A third metabolite found in 
all 3 insects co-chromatographed with 2-N-methylcarbamoyl -3-methyl-5- 
pyrazolyl dimethylcarbamate and exhibited the same biological activity 
(Zubairi and Casida, 1965). 
Labeled dimetilan was administered orally to rats. Within 4 hours 
after treatment, the urine contained 10% of the administered radioactiv- 
ity and an additional 3% within the next 18 hours. Two metabolites were 
recovered but not identified (Zubairi and Casida, 1965). 
Other studies have shown a microsomal system, requiring TPNH and 
oxygen, that acts on N,N-dialkyl carbamates. Dealkylation occurs with 
formation of formaldehyde from N,N-dimethylcarbamates but not from 
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