Structure-activity relationships of various amino-hydroxy-benzenesulfonic acids and sulfonamides as tyrosinase substrates.

Background: o-Aminophenols have been long recognised as tyrosinase substrates. However their exact mode of interaction with the enzyme's active site is unclear. Properly vic-substituted o-aminophenols could help gain some insight into tyrosinase catalytic mechanism.

Design of a new and highly effective chiral auxiliary for Diels-Alder reaction of 1-aminodiene.

A theoretical investigation of the facial selectivity of optically active oxazolidin-2-one-substituted dienes has been realized. This analysis enabled the development of (R)-4-phenyloxazolidin-2-thione as a very effective chiral auxiliary for cycloaddition of 1-aminodiene.

Influence of diene substitution on transition state stabilization in Diels-Alder reaction.

A theoretical analysis of transition state stabilization in D-A reactions of substituted dienes according to the nature and position of the substituent has been carried on. Results revealed that substituents (de)stabilize TS through four effects (steric, mesomeric, inductive, and polarizability) acting principally by favoring the electronic transfer between the two partners. The correlations observed point out nevertheless that the reactivity of substituted dienes in [4 + 2] cycloadditions on ethylene may principally be predicted by the sole use of the F + R electronic parameters.