“…These were the semiempirical method AM1 18 as implemented in MOPAC93 (Software release 2002, Stewart, J. J. P.) and the ab initio method B3LYP/6-31G** as provided by the Gaussian 98 (Gaussian 98 revision A.7, Gaussian Inc., Pittsburgh, PA) package. All calculations included geometry optimization, employing CORINA 2001 22,23 to generate initial 3D structures from Simplified Molecular Input Line Entry Specification (SMILES) strings, followed by SYBYL force field geometry optimizations (SYBYL version 6.8, Tripos Associates, St. Louis, MO) before starting quantum chemical calculations. 16 Because no conformational search routines were employed it may well be that, in individual cases, the finally achieved geometry does not represent the energy minimum of the conformational space.…”