Catecholamine Derivatives: Natural Occurrence, Structural Diversity, and Biological Activity.

Catecholamines (CAs) are aromatic amines containing a 3,4-dihydroxyphenyl nucleus and an amine side chain. Representative CAs included the endogenous neurotransmitters epinephrine, norepinephrine, and dopamine. CAs and their derivatives are good resources for the development of sympathomimetic or central nervous system drugs, while they also provide ligands important for G-protein coupled receptor (GPCR) research.

Bioactivity-guided isolation of compounds from with antibacterial activity against .

Bioactivity-guided fraction of an extract of to identify antibacterial compounds against , led to the isolation of two new compounds, (2″)-5-methoxy-7-hydroxy-8-lavandulylchromone (13) and (2,)-(-)-sophobiflavonoid CE (19), and 18 known flavonoids, (6a,11a)-(-)-maackiain (1), (2)-(-)-8-prenylnaringenin (2), (2)-(-)-exiguaflavanone K (3), (2)-(-)-sophoraflavanone G (4), (2)-(-)-leachianone A (5), (2)-(-)-kushenol E (6), (2)-(-)-leachianone G (7), (±)-kushenol F (8), (2)-(-)-kurarinone (9), (2)-(-)-kurarinol (10), (2 ,3)- (+)-3,7,4'-trihydroxy-5-methoxy-8-prenylflavanone (11), (2)-(-)-isoxanthohumol (12), (2)-(-)-2'-methoxykurarinone (14), (2 ,3)-(+)-kushenol I (15), calycosin (16), kuraridin (17), (2)-(-)-kushenol A (18), and trifolirhizin (20). Their structures were elucidated based on NMR, MS, and CD spectroscopic analysis. Among them, , , , and exerted modest antibacterial activity against , with MIC of 128-256 μg/mL for and 256-512 μg/mL for , and .