We purified repanol from the crude extract and determined its 1 H NMR spectrum, confirming this structural assignment. The raw 1 H NMR spectrum is provided in .jdxformat as a Supporting Information. This result exemplifies how RuAAC derivatization can be useful in confirming the presence of internal alkyne moieties in unknown compounds in crude extracts. The intense signal observed for our RuAAC-derivative and comparatively weak signal for the underivatized sample (Figure ) again confirms that RuAAC as conducted here can usefully boost signal for the detection of internal alkynes. Our discovery of a novel internal alkyne in the human diet underscores the need for analytical techniques such as RuAAC that target this unique moeity.