LAUSR

Abstract In this article we propose an improved statistical approach for the estimation of the mole fraction of each conformer in a given conformational equilibrium from the measured averaged 13C NMR chemical shifts. As each compound has a different number of conformers, an iterative process of fitting (backfitting type) is necessary. In each iteration, two estimates are made, i) fitting to a ridge regression model with equality and inequality constraints and selection of variables for each compound and ii) re-fitting for all compounds. This new procedure leads to consistent results, with low standard error and good p-values, allowing the estimation of the conformational composition for small molecules with a reduced number of conformers.