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Logic Puzzle #15: Multiple Molecular Formulae



When the spectral data is sparse, the list of potential candidate structures can seem endless. The task then becomes sifting through the spectral data as a means to filter the candidates. The purpose of this puzzle is to perform such a task.

The following unknown compound with a mass of 380.1 +/- 0.5 Da comprises of the atoms C, H and O. There are 13 to17 carbon atoms expected, a minimum of 18 hydrogen atoms and a minimum of 1 oxygen atom. An expansion of the aromatic region of a 1H NMR spectrum is also provided. Given the following criteria, can the list of molecular formulae be dwindled down?

#              MF              Accurate Mass  Mass Difference   RDBE

1        C14H20O12          380.095476       -0.004524         5.0

2        C15H24O11          380.131862        0.031862         4.0

3        C16H28O10          380.168247        0.068247         3.0

4        C17H32O9            380.204633        0.104633         2.0

Logic#15MF_RDBE_Apr282011