Hydroxydanaidal

Hydroxydanaidal is an insect pheromone synthesized by some species of moth from pyrrolizidine alkaloids found in their diet.

Hydroxydanaidal

Names
IUPAC name 7-Hydroxy-6,7-dihydro-5H-pyrrolizin-1-carboxaldehyde
Identifiers
CAS Number	34199-35-4
3D model (JSmol)	Interactive image
ChemSpider	142107
PubChem CID	161805
UNII	CCJ9N9N4QT Y
CompTox Dashboard (EPA)	DTXSID60955744
InChI InChI=1S/C8H9NO2/c10-5-6-1-3-9-4-2-7(11)8(6)9/h1,3,5,7,11H,2,4H2 Key: QJXKHTIRIREIAG-UHFFFAOYSA-N
SMILES O=Cc1ccn2CC[C@@H](O)c12
Properties
Chemical formula	C8H9NO2
Molar mass	151.165 g·mol−1
Appearance	Solid
Melting point	55 °C (131 °F; 328 K)[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Use

The caterpillars of several kinds of arctiid moth ingest pyrrolizidine alkaloids—substances which plants produce to deter herbivores—and use them as protection against insectivores. The larva converts the alkaloid into an N-oxide for storage; on metamorphosis, the alkaloid is retained and used by the adult. This was discovered after the observation that Utetheisa ornatrix moths caught in spiderwebs were cut loose by the spiders.

Many insects that carry pyrrolizidine alkaloids are brightly-colored to signal their toxicity.

Male tiger moths convert the alkaloid through various intermediate stages^[2] into the pheromone hydroxydanaidal;^[3] female moth prefer males with more pheromone, since the alkaloid will be transferred into her eggs and protect them from predation.