4-methylquinazoline is a minor component of the male sex pheromone in Nasonia vitripennis.

We identified 4-methylquinazoline (4-MeQ) as a minor component of the male sex pheromone of the parasitoid Nasonia vitripennis. Like the major components (4R,5R)- and (4R,5S)-5-hydroxy-4-decanolide (HDL), 4-MeQ is synthesized in the abdomen of males. At doses of 6 or 1 ng, 4-MeQ synergized the response of virgin females to the HDL-diastereomers in a still-air olfactometer, but was not attractive as a single component. 4-MeQ is also responsible for the characteristic medicinal odor of N. vitripennis males.