This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Monolignols.svg Skeletal formulae of the three main monolignol compounds from top paracoumaryl alcohol numbered coniferyl alcohol and sinapyl alcohol Created using acdlabs html ACD and Inkscape Own work after Image MonolignolStructure Fvasconcellos January UTC Image MonolignolStructure by Chino px Phenylpropanoids