The configuration and conformation of nicandrenone, isolated from Nicandra physalodes, are described using molecular modeling and NMR NOESY techniques. Amsterdam Density Functional (ADF) software was used, and the structures were those reduced to minimum energy molecular models, utilizing B3LYP executions and Density Functional Theory (DFT). The first spectral proof that this withanolide has a 22-R configuration is also provided. This method may be adaptable to other natural products.
Amsterdam Density Functional (ADF) software was obtained from Scientific Computing & Modelling NV, Amsterdam, The Netherlands.
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