Iterative method for finding the low-energy conformations based on the concept of molecular volumes

The recently proposed overlapping spheres (OS) method (Raos, N. Croat Chem Acta 1999, 72, 727) finds low-energy conformations by minimizing the repuls ion potential dependent on the free molecular volume inside the sphere with radius R-v. The sphere is situated at the geometrical center of the molecu le or at the center of a molecular segment. The method was checked on branc hed alkanes and cyclic molecules (1,4-diethylcyclohexane and copper(II) mon ochelates with N-alkylated amino acids), yielding in all cases stable confo rmations with usually lower conformational energy than the "seed" conformat ions. The simple rules for segmentation of a molecule, based mostly on the topological considerations, were derived from the results of successfull op timizations. (C) 2000 John Wiley & Sons, Inc.