2) nzyme’s protein scaffold is to hold the zinc ion, coenzyme, and
3) eversible and when the relative concentration of ethanol is high,
The role of the e
substrate in the three-dimensional array required to lower the energy of the
transition state.
The reaction is r
alcohol dehydrogenase carries out the oxidation of ethanol ⇒ alcohol
dehydrogenase is important in detoxication.
The Chemistry of Stereoselective Reductions of Carbonyl Groups
- Enantioselectivity:
tructure about the carbonyl group that is being reduced, the
i) ents like NaBH 4 and LiAlH 4 , react with equal rates at either face of
ii) e
2) When enzym
i) he new stereocenter may
- Re anar center:
1) Depending on the s
tetrahedral carbon that is formed by transfer of a hydride could be a new
stereocenter.
Achiral reag
an achiral trigonal planar substrate, leading to a racemic form of the product.
Reactions involving a chiral reactant typically lead to a predominance of on
enantiomeric form of a chiral product ⇒ an enantioselective reaction.
es like alcohol dehydrogenase, are chiral, reduce carbonyl groups
using coenzyme NADH, they discriminate between the two faces of the trigonal
planar carbonyl substrate, such that a predominance of one of the two possible
stereoisomeric forms of the tetrahedral product results.
If the original reactant was chiral, the formation of t
result in preferential formation of one diastereomer of the product ⇒ a
diastereoselectiv reaction.
and si face of a trigonal pl
1) Re is clockwise, si is counterclockwise.
