A rational approach to predict and modulate stereolability of chiral alpha substituted ketones.
An effective strategy to assess and modulate the stereolability of chiral alpha substituted ketones (C alpha SKs) is presented. The tendency of C alpha SKs to retain or change their configuration in water is analyzed as a function of thermodynamic proton-release attitude of alpha asymmetric atoms inside the structures by linear Brønsted correlations. A molecular modeling procedure was developed to analyze and suggest chemical modifications of C alpha SKs in view to obtain the desired grade of stereochemical stability. The approach was employed to predict the tendency to enantiomerize in water of two ketones (1 and 2) endowed with inhibitory activity against monoamine oxidases (MAOs) and the results were confirmed by experimental kinetics measurements performed in organic medium. As a demonstration of practical potentialities of the approach, four new structures, conceived as simple chemical modifications of 1 and 2, were designed to improve/reduce the stereostability grade of the starting anti-MAO ketones. The possibility to extend easily the procedure to other classes of C-H acids appears of interest.
Istituto Superiore di Sanità, Dipartimento del Farmaco, Rome, Italy.
Roberto
R
Cirilli
Roberta
R
Costi
Roberto
R
Di Santo
Francesco
F
Gasparrini
Francesco
F
La Torre
Marco
M
Pierini
Gabriella
G
Siani
D000097:Acetonitriles / Q000737:chemistry; D002244:Carbon / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D007659:Ketones / Q000737:chemistry*; D007700:Kinetics; D008958:Models, Molecular; D008996:Monoamine Oxidase Inhibitors / Q000737:chemistry*; D011759:Pyrrolidines / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
D000097:Acetonitriles; D007659:Ketones; D008996:Monoamine Oxidase Inhibitors; D011759:Pyrrolidines; D014867:Water; D002244:Carbon; D006859:Hydrogen; C032519:pyrrolidine; C032159:acetonitrile