Nepetalactol is an iridoid.

It is produced from 8-oxogeranial by the enzyme iridoid synthase.

[1] Nepetalactol is a substrate for the enzyme iridoid oxidase (IO) which produces 7-deoxyloganetic acid.

It has been identified in Actinidia polygama (the silver vine) as a major cat attractant, and a mosquito repellent.

The fact that mosquitos bite cats with nepetalactol on their fur less often may explain why cats are attracted to silver vine in the first place.