ABSTRACT:Two new acridone alkaloids, chlorospermines A
and B (1and2), were isolated from the stem bark ofGlycosmis
chlorosperma, together with the known atalaphyllidine (3) and
acrifoline (4), by means of bioguided isolation using an in vitro
enzyme assay against DYRK1A. Acrifoline (4) and to a lesser
extent chlorospermine B (2) and atalaphyllidine (3) showed
significant inhibiting activity on DYRK1A with IC
50
’s of 0.075,
5.7, and 2.2 μM, respectively. Their selectivity profile was
evaluated against a panel of various kinases, and molecular
docking calculations provided structural details for the
interaction between these compounds and DYRK1A