Ximenynic acid is trans-11-octadecen-9-ynoic acid, a long-chain acetylenic fatty acid.
It was discovered in the fruit kernels of three species of South American plants in the genus Ximenia, after which it is named. and found to have the formula C<sub>18</sub>H<sub>30</sub>O<sub>2</sub>.
It can be extracted from the fruit kernels of the Santalum obtusifolium (Sandalwood) and the Australian sandalwood Santalum spicatum
It is also found in seed oil of other plants in the Santalaceae family, including the native cherry Exocarpos cupressiformis and sweet quandong Santalum acuminatum.
It was the subject of a 2003 European patent (for use in food). The patent application was deemed withdrawn in August 2012.
It is used in some skincare products.