51918-79-7Relevant academic research and scientific papers
EANTIOSELECTIVITY OF THE MICROSOMAL EPOXIDE HYDROLASE: HYDROLYSIS OF (+/-)-CIS-3-BROMO-1,2-EPOXYCYCLOHEXANE
Bellucci, Giuseppe,Ferretti, Maria,Lippi, Annalisa,Marioni, Franco
, p. 2715 - 2720 (2007/10/02)
The acid-catalysed and the rabbit microsomal epoxide hydrolasa-catalysed hydrolysis of (+/-)-cis-3-bromo-1,2-epoxycyclohexane (1) have been investigated.Both reactions were completely regio- and stereo-specific, giving t-3-bromocyclohexane-r-1,t-2-diol (2) as the only product.Epoxide (1) was found to be a much better substrate for the epoxide hydrolase than its trans-diastereoisomer.Under enzyme saturation conditions the hydrolysis was fairly eneantioselective, as shown both by the biphasic shape of its kinetic profile and by the isolaton of optically active (-)-(1R,2R,3S)-(1) and (-)-(1R,2S,3R)-(2) at incomplete reaction.The absolute configurations have been deduced by correlation with (-)-(R,R)-trans-cyclohexane-1,2-diol.At about 30percent conversion, the enantiomeric excesses of unchanged (1) and formed (2) were 24-30percent and 56-60percent, respectively, and racemic (2) was obtained after complete hydrolysis.The results have been rationalized by a competitive inhibition of (+)-(1S,2S,3R)-(1) on the hydrolysis of (-)-(1) and fit the previously proposed picture describing the substrate enantioselection carried out by the microsomal epoxide hydrolase.
