Reference

Comparative metabolism of the six stereoisomers of phenothrin in rats and mice

Comparative metabolism of the six stereoisomers of phenothrin in rats and mice. Izumi, Toshihiko; Kaneko, Hideo; Matsuo, Masatoshi; Miyamoto, Junshi (Takarazuka Res. Cent., Sumitomo Chem. Co., Takarazuka 665, Japan). Nippon Noyaku Gakkaishi, 9(2), 259-67 (English) 1984. CODEN: NNGADV. ISSN: 0385-1559. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) Metab. of phenothrin (I) isomers in mice and rats was studied. On single oral administration of (1R, trans)-I (II) [26046-85-5], (1RS, trans)-I (III) [51186-86-8], (1S, trans)-I, (IV) [66036-31-5], (1R, cis)-I (V) [51186-88-0], (1RS, cis)-I (VI) [51186-87-9], and (1S, cis)-I (VII) [51134-88-4] 14C-labeled at the benzyl a position to mice and rats at 10 mg/kg, the 14C was almost completely eliminated from the bodies within 6 days after administration, giving tissue 14C at generally very low levels. Both species showed little difference in the 14C elimination rate and tissue 14C levels between II and III and between V and VI, whereas IV and VII administration resulted in somewhat lower 14C recoveries in excreta and higher 14C levels in fat than II and V, resp. Urine was the major 14C excretion route for II, III, and IV; whereas feces were the major route for V, VI, and VII. Both species gave larger amts. of ester-cleaved metabolites from II, III, and IV than from V, VI, and VII. Major urinary and fecal metabolites were common to both species, except N-(3-phenoxybenzoyl)taurine (VIII) [69519-14-8], which was excreted only by mice. Ester hydrolysis and hydroxylation at the 3-position of the phenoxy ring occurred to a larger extent in rats than in mice. VIII and 3-(4-hydroxyphenoxy)benzoic acid (IX) [35065-12-4] were major urinary metabolites of II, III, and IV by mice, whereas IX sulfate [58218-91-0] was the predominant metabolite of II, III, and IV by rats. Metab. of 1RS isomers proceeded similarly to resp. 1R isomers rather than to resp. 1S isomers.

Comparative metabolism of stereoisomers of cyphenothrin and phenothrin isomers in rats

Comparative metabolism of stereoisomers of cyphenothrin and phenothrin isomers in rats. Kaneko, Hideo; Matsuo, Masatoshi; Miyamoto, Junshi (Takarazuka Res. Cent., Sumitomo Chem. Co., Takarazuka 665, Japan). Nippon Noyaku Gakkaishi, 9(2), 237-47 (English) 1984. CODEN: NNGADV. ISSN: 0385-1559. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) On single oral or s.c. administration of (1R, trans)-cyphenothrin (I) [39515-40-7] or its cis-isomer (II) (14C-labeled at the CO group or the benzyl a-position) to male rats at 2-4 mg/kg, the 14C was excreted rapidly and almost completely into urine and feces within 7 days after administration, giving very low tissue 14C levels. Similar treatments with I- and II-cyano-14C resulted in slower and incomplete 14C elimination, including partial elimination into expired air, and higher tissue 14C levels, esp. in hair, skin, stomach, and stomach contents. I and II were metabolized mainly through ester cleavage, oxidn. of Me2C:CH2 and gem-Me2 groups, hydroxylation of the phenoxy ring, conversion of cyanide to thiocyanide and CO2, and conjugation of formed acids, alcs., and phenols. I was more susceptible to ester hydrolysis, and larger amts. of metabolites retaining the ester linkage were obtained from II than from I. No difference was obsd. between oral and s.c. administration in tissue 14C levels or in the nature of metabolites, except that s.c. administration gave larger amts. of ester-cleaved metabolites than oral administration. Half-lives of 14C in 3 tissues of rats orally dosed with I, II, (1R, trans)-phenothrin (III) [26046-85-5], and the cis-isomer of III (IV) [51186-88-0] were 2.5-3.0, 3.8-4.8, 2.8-3.7, and 4.5-6.9 h, resp. The rate of hydrolysis by rat hepatic esterase [9013-79-0] were in the order of III 3 I > II > IV, whereas plasma esterase hydrolyzed III and IV more rapidly than I and II without trans-cis selectivity.