(3Z)-Nonenal

(3Z)-Nonenal is an unsaturated aldehyde that occurs naturally in various plants.

Occurrence
(3Z)-Nonenal is a flavor component in various plants, such as cucumber, honeydew melon, and soy. It is the biosynthetic precursor to (2E)-nonenal, formed by isomerases. It also occurs in the brown algae Laminaria angustata. In the oysterplant, it contributes to its oyster-like taste.

Biosynthesis
In various plants such as cucumbers and melons, (3Z)-nonenal is formed from linoleic acid to 9-hydroperoxy-10,12-octadecadienoic acid and its splitting. In Laminaria angustata, formation also occurs via arachidonic acid and its 12-hydroperoxide.

Synthesis
(3Z)-Nonenal can be synthesized by oxidation of (3Z)-nonen-1-ol with pyridinium chlorochromate. The compound can also be obtained through a multi-step reaction starting from 1,4-butanediol.

Properties
The scent is described as fruity, melony, or maritime in low concentrations. In an in vitro study, (3Z)-nonenal acted as a fungicide against various types of fungi.