40642-83-9Relevant academic research and scientific papers
Mechanistic studies on the cytochrome P450-catalyzed dehydrogenation of 3- methylindole
Skiles,Yost
, p. 291 - 297 (1996)
The mechanism of 3-methyleneindolenine (3MEI) formation from 3- methylindole (3MI) in goat lung microsomes was examined using stable isotope techniques. 3MEI is highly electrophilic, and its production is a principal factor in the systemic pneumotoxicity of 3MI. Noncompetitive intermolecular isotope effects of (D)V = 3.3 and (D)(V/K) = 1.1 obtained after deuterium substitution at the 3-methyl position indicated either that hydrogen abstraction from the methyl group was not the initial rate-limiting step or that this step was rate-limiting and was masked by a high forward commitment and low reverse commitment to catalysis. An intramolecular isotope effect of 5.5 demonstrated that hydrogen atom abstraction was probably the initial oxidative and rate-limiting step of 3MI bioactivation or that deprotonation of an aminium cation radical, produced by one-electron oxidation of the indole nitrogen, was rate-limiting. However, a mechanism which requires deprotonation of the aminium cation radical is probably precluded by an unusual requirement for specific base catalysis at a site in the cytochrome P450 enzyme other than the heme iron. The pattern of 18O incorporation into indole-3-carbinol from 18O2 and H218O indicated that approximately 80% of the indole-3-carbinol was formed in goat lung microsomes by hydration of 3MEI. However, the inverse reaction, dehydration of indole-3-carbinol, did not significantly contribute to the formation of 3MEI. These results show that 3MEI was formed in a cytochrome P450-catalyzed dehydrogenation reaction in which the rate-limiting step was presumably hydrogen atom abstraction from the 3-methyl position. The ratio of the amounts of 3MEI to indole-3-carbinol formed (50:1) indicated that dehydrogenation of 3MI is an unusually facile process when compared to the dehydrogenation of other substrates catalyzed by cytochrome P450 enzymes.
1-and 2-azafulvenes
Barcock,Moorcroft,Storr,Young,Fuller
, p. 1187 - 1190 (2007/10/02)
Flash pyrolysis of dialkylaminopyrroles and thermolysis of 2-pyrrylmethyl phenyl sulfoxide at 65°C in solution gave azafulvenes which were trapped with a variety of nucleophiles.
