Terpenoid glycosides

Picrocrocin is a monoterpene glycoside precursor of safranal. It is found in the spice saffron, which comes from the crocus flower. Picrocrocin has a bitter taste, and is the chemical most responsible for the taste of saffron.

right|thumb|200px|Cucurbit-5-ene with standard carbon numbering right|thumb|200px|3D structure of cucurbitacin E as found in the [[crystal structure]]

Ptaquiloside is a norsesquiterpene glucoside produced by bracken ferns (majorly Pteridium aquilinum) during metabolism. It is identified to be the main carcinogen of the ferns and to be responsible for their biological effects, such as haemorrhagic disease and bright blindness in livestock and oesophageal, gastric cancer in humans. Ptaquiloside has an unstable chemical structure and acts as a DNA alkylating agent under physiological conditions. It was first isolated and characterized by Yamada and co-workers in 1983.