Pyrrolines, also known under the name dihydropyrroles, are three different heterocyclic organic chemical compounds that differ in the position of the double bond. Pyrrolines are formally derived from the aromate pyrrole by hydrogenation. 1-Pyrroline is a cyclic imine, whereas 2-pyrroline and 3-pyrroline are cyclic amines.
Notable examples of pyrrolines containing various substituents include:
2-Acetyl-1-pyrroline, an aroma compound with a white bread-like smell
Thienamycin, a beta-lactam antibiotic
MTSL, a chemical used for certain NMR experiments
Pyrrolysine, an unusual proteinogenic amino acid
1-Pyrroline-5-carboxylic acid, a biosynthetic metabolite
Porphyrin, consisting of two alternating pairs of pyrrol and pyrroline connected via methine (=CH-) bridges
N-substituted pyrrolines can be generated by ring-closing metathesis.