Reference

Immunochemical detection of cytochrome P 450 isozymes induced in rat liver by n-hexane, 2-hexanone and acetonyl acetone

Immunochemical detection of cytochrome P 450 isozymes induced in rat liver by n-hexane, 2-hexanone and acetonyl acetone. Nakajima, Tamie; Elovaara, Eivor; Park, Sang S.; Gelboin, Harry V.; Vainio, Harri (Sch. Med., Shinshu Univ., Matsumoto 390, Japan). Arch. Toxicol., 65(7), 542-7 (English) 1991. CODEN: ARTODN. ISSN: 0340-5761. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) Section cross-reference(s): 7 Cytochrome P 450 isoenzymes induced in rat liver by treatment with n-hexane, 2-hexanone and acetonyl acetone (given i.p., 5 mmol/kg for 4 days) were investigated using enzyme assays (benzene, toluene, 7-ethoxyresorufin and 7-pentoxyresorufin metab.) and monoclonal antibodies (anti-P450IA1/2, antiP450IIb1/2, anti-P450IICl1/6, anti-P450IIE1(91) and anti-P450IIE1(98)). n-Hexane treatment enhanced the activities of low-Km benzene arom. hydroxylase and toluene side-chain oxidase, but not 7-ethoxyresorufin O-deethylase or 7-pentoxyresorufin O-depentylase. 2-Hexanone or acetonyl acetone treatment enhanced the activities of low- and high-Km benzene arom. hydroxylases, toluene side-chain oxidase and 7-pentoxyresorufin O-depentylase, but not of 7-ethoxyresorufin O-deethylase. Immunoblot anal. showed that anti-P450IA1/2 did not bind liver microsomal protein from either control and treated rats in the region of cytochrome P450s, whereas with anti-P450IIE1(98) a clear-cut band was seen in liver microsomes from control and treated rats, with intensities in the following order: 2-hexanone = acetonyl acetone 3 n-hexane > control > phenobarbital. With anti-P450IIB1/2, a band was detected in microsomes from phenobarbital-treated rats, and to a lesser extent, in microsomes from 2-hexanone- and acetonyl acetone-treated rats. Like the immunoblot anal., anti-P450IIE1(91) inhibited toluene side-chain hydroxylase activity in all microsomes, except in prepns. from phenobarbital-treated rats and anti-P450IIB1 in microsomes from phenobarbitol-, 2-hexanone- and acetonyl acetone-treated rats. Anti-P450IIC11/6 also inhibited toluene side-chain hydroxylase activity: the inhibited activity in the five different microsome prepns. was as follows: n-hexane = control > acetonyl acetone = 2-hexanone = phenobarbital. These results indicate that n-hexane induces only quant. alterations in the constitutive cytochrome P 450 isoenzyme (P450IIE1), whereas its metabolites 2-hexanone and acetonyl acetone induce not only quant. changes in constitutive cytochrome P 450 (P450IIE1 and P450IIC11/6) but also a different type of isoenzyme (P450IIb1/2).

Selective reduction of unsaturated ketones to unsaturated alcohols catalyzed by an iridium-phosphine system

Selective reduction of unsaturated ketones to unsaturated alcohols catalyzed by an iridium-phosphine system. Visintin, Maura; Spogliarich, Roberto; Kaspar, Jan; Graziani, Mauro (Ist. Chim., Univ. Trieste, Trieste, Italy). J. Mol. Catal., 24(3), 277-80 (English) 1984. CODEN: JMCADS. ISSN: 0304-5102. DOCUMENT TYPE: Journal CA Section: 23 (Aliphatic Compounds) Section cross-reference(s): 29, 67 The system formed in situ from [Ir(COD)Cl]2 (COD = 1,5-cyclooctadiene) and P(C6H4OMe-2)3 catalyzed the selective transfer hydrogenation of the CO group in H2C:CHCH2CH2COMe, the yield in unsatd. alc. H2C:CHCH2CH2CHMeOH being max. at high P-Ir ratios. This was related to an intramol. interaction between the substrate and the MeO groups of the phosphine. The same system reacted with PhCH:CHCOMe, yielding unsatd. alc. together with satd. ketone and alc. 2-Hexanone was also reduced to the alc. Sterically crowded Me2C:CHCH2CH2COMe gave only the unsatd. alc. on redn.