ABSTRACT
Infrared (IR) spectroscopy has been widely used in the structural elucidation of pyrethrins and related compounds since 1950 and two analytical methods in the IR spectroscopy. L. Crombie stressed the importance of IR spectra for determining the purity and for elucidation of the structure of compounds in this series, compounds which are often viscous liquids of high boiling points and which do not give derivatives readily. The chapter focuses on utilization of IR spectroscopy for the characterization of plant hormones. Plant growth substances which fall under such groups of compounds as aliphatic compounds, fatty acids, phenolic and other aromatic compounds, nitrogen and sulfur heterocycles, alkaloids, terpenes, and steroids, have been isolated from several plant and fungal species. The IR spectra of purines and adenines have been extensively investigated because these compounds constitute an important class of biologically active products. The various functional groups present in the indole auxins are identified by IR spectroscopy.
