LMOD method

A conformational search carried out on BQ123 included flat-well harmonic restraints between two backbone hydrogen bonds in the potential energy function. Four of the resulting structures were found to compare favorably with one of the 20 NMR-derived structures. The LMOD method is thus proposed to be a promising technique for carrying out conformational analysis on molecules of the size described here and for aiding in the interpretation of NMR data on such molecules, where multiple conformations contribute to the observed data. 

Methods that operate in Cartesian space, although generally not particularly effective, can be used for generating ring conformations Just as acyclic conformations, because ring closure need not be considered. The low-mode procedure described above shares this advantage with the Cartesian methods, but LMOD has proven to be equally suited for cyclic as well as acyclic structures. 

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