Insecticidal and the anticholinesterase activity of m-acylamidophenyl and m-thioureidophenyl N-methylcarbamates

Abstract

SACHER, OLINand only one sample of 2,4-D contained measurable amounts of the hexa isomers. The hexa isomers present presumably were there because of tetrachlorophenol impurities which condensed with each other. Higher dioxins were found in some samples of several other pesticides, including erbon, tetradifon, ronnel, sesone, and DMPA.The dioxin content of the 20 chlorophenol samples is also presented in Table 111. No TCDD was detected in any sample at levels above 0.5 ppm. However, the higher dioxins were plentiful. Trichlorophenol contained only small amounts of hexachlorodibenzo-p-dioxin and no sample contained over 10 ppm. Tetrachlorophenol contained less than 100 ppm of hexa-, hepta-, and octachlorodibenzo-p-dioxins, while six of 20 pentachlorophenol samples contained over 100 ppm of the hepta-and octachlorodibenzo-p-dioxin isomers. An infrared spectrum of a pentachlorophenol extract is presented in Figure 2. It is quite obvious that the extract contains octachlorodibenzo-p-dioxin when the spectrum is compared to the standard octachlorodibenzo-p-dioxin spectrum. Analysis by ec-gc indicated both hepta-and octachlorodioxins were present in the sample. This may account for the peak broadening. The reason for the high amounts of dioxin in chlorophenol is probably due to heat treatment during synthesis. As chlorination of phenol proceeds past the dichlorophenol stage, heat must be supplied in order to keep the reaction mixture in a melt condition. Since heat is being supplied in the presence of chlorophenols, the formation of higher chlorinated dibenzo-p-dioxins might be expected. The rate and time of melt heating probably governs the formation and amounts of the various dioxin isomers. If the chlorination temperature is raised too high too quickly, the lower chlorinated dioxins may be formed since the lower chlorophenols would be present and available for reaction with each other. If the temperature is raised too high after nearly all chlorophenol is in the penta form, octachlorodibenzo-p-dioxin would be the predominant impurity formed.In conclusion, TCDD has been present at levels above 0.5 ppm in the past, but was less than 0.5 ppm in the current production samples examined. Higher chlorodioxins are present predominantly in chlorophenols with the highest amounts present in pentachlorophenol. Thirty-eight percent of all samples examined contained at least one chlorodioxin, with many containing more than one.Fifty-nine new N-methyl and N,N-dimethylcarba-gized effectively by 2,3-methylenedioxynaphthalene. mates were synthesized and tested as insecticides Structure-activity correlation revealed that maximal and as inhibitors of fly and bovine cholinesterases.anticholinesterase activity is associated with a In spite of the high anticholinesterase activity ex-definite size of the alkyl substituent on the amide hibited by many of these compounds, only few or the thiourea grouping. In all series tested, chemicals have shown insecticidal activity. Fur-alkyl substituent with four to six carbon atoms thermore, these compo...

Insecticidal and anticholinesterase activity of benzotriazolyl methyl and dimethylcarbamates

“…Cholinesterase Determinations. The procedure described by Sacher and Olin (1972) was used for the enzyme determinations. Briefly, the cholinesterase was incubated with the carbamates for 12 min, utilizing a Technicon Autoanalyzer apparatus (Winter, 1960).…”

“…Two-day-old susceptible female houseflies (Musca domestica L. Snaidm strain) were utilized for the fly toxicity measurements. Flies were treated topically as described by Sacher and Olin (1972). For the synergism studies flies were treated as above with a carbamate-2,3methylenedioxynaphthalene combination at a 1:1 ratio (w/w).…”

Parameters for Carbamate Pesticide QSAR and PBPK/PD Models for Human Risk Assessment

“…Replacing the carbamate linkage (OC (O) N) with thiol (SC=O), thiono (OC=S), or dithio (SC=S) reduced the antiChE activity of 2-isopropylphenyl N,N-dimethylcarbamate by 12 to 40 times (Petrovskii 1970). Fifty-nine new N-methyl and N N N,N-dimethylcarbamates, meta-N N acylamidophenyl and meta-thioureidophenyl, were synthesized and tested as inhibitors of fl y and bovine ChEs (Sacher and Olin 1972). Structurefl activity correlation indicated that maximal antiChE activity was associated with a definite size of the alkyl substituent on the amide or thiourea groupfi ing, with four to six carbons producing the most potent inhibitors.…”

The Thyroid Dance: Nursing Approaches to Autoimmune Low Thyroid

“…Serum tests that measure thyroid activity include the following (compiled from Kasten et al, 2001;Kuritzky, 2001;Noble, 2001;Sacher, McPherson, & Campos, 2000;Shames & Shames, 2001).…”