This chapter deals with the structural elucidation of natural products using
UV-visible, FT-IR, NMR (1D and 2D) spectroscopy and Mass spectrometry. Key
concepts associated with these techniques are introduced here. Various spectra of
natural compounds have been included with a brief discussion of the functional groups
and structural features that they reveal. The use of these spectroscopic techniques in
drug discovery from natural products has been reviewed, highlighting the advantages
of these techniques. The importance of each technique is discussed with suitable
examples of natural products obtained from medicinal plants. Some of these
techniques, such as FT-IR and NMR spectroscopy, are primarily used for identification
purposes; while UV-visible spectroscopy and mass spectrometry are used for the
purpose of analysis and structural elucidation. Recent advancements in the isolation
techniques such as counter-current chromatography, supercritical fluid
chromatography, preparative high-performance liquid chromatography (prep-HPLC),
and preparative gas chromatography (prep-GC) have made the availability of novel
natural compounds from plants possible for their structural elucidation and biological
screening. Development of hyphenated techniques such as LC-NMR, UPLC-MS, and
GC-MS have made simultaneous isolation and structural elucidation of natural
products achievable. In this chapter, we have summarized basic principles of UVvisible,
FT-IR, 1D and 2D NMR spectroscopy and mass spectrometry and their role in
the determination of structures of natural compounds citing suitable examples.
Keywords: FT-IR Spectroscopy, Mass Spectrometry, Natural Products, NMR
Spectroscopy, UV-visible Spectroscopy, Structural Characterization.
