A new clerodane diterpenoid, crotolanin A (1), along with three known clerodane diterpenoids, crotoeurin B (2), teucvidin (3) and teucvin (4), was isolated from the ethanol extract of the leaves and twigs of Croton lachnocarpus Benth. Their structures were identified by extensive NMR spectroscopic and HRESIMS analyses. The dopaminergic neuroprotective activity of compounds 1-4 was tested by using transgenic Caenorhabditis elegans pathological model. Compound 2 alleviated dopaminergic neuron degeneration of worms induced by 6-hydroxydopamine (6-OHDA) that represented a potential therapy for Parkinson's disease (PD).
Keywords: Caenorhabditis elegans; Croton lachnocarpus Benth.; Euphorbiaceae; clerodane diterpenoid; dopaminergic neuroprotective activity.