A Simple Algorithm for Superimposing Sets of NMR Derived Structures: Its Application to the Conformational Study of Cephalomannine in Lipophobic and Lipophilic Solution

A simple iterative method for superimposing sets of NMR derived structures and calculation of the root mean square deviation (RMSD) of the sets is described. It was compared to the commonly used algorithm involving pairwise best fitting in the conformational study of the taxoid anticancer drug cephalomannine in lipophobic and lipophilic solvents. Lower RMSD values were obtained, indicating a better superposition of the structures in the sets. The conformations of cephalomannine in the two solvent systems reported are in good agreement with earlier conformational studies on other active taxoids.

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