Quinolizidines

**Definition:** Saturated quinolizines that are two fused six-membered rings with a nitrogen atom at the ring fusion. They are biosynthesized in PLANTS by cyclization of a LYSINE coupled to CADAVERINE. Many of them are naturally occurring ALKALOIDS.

**Tree numbers:** - D03.633.100.834.737

**Synonyms:** - Quinolizidine