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During this study, one new coumarin; 7-O-β-D-glucopyranoside-2H-1-benzopyran-2-one (1) and three quinoline alkaloids; 3-hydroxy, 2, 2, 6-trimethyl–3, 4, 5, 6-tetrahydro-2H-pyrano[3,2-c] quinoline 5-one (2), ribalinine (3) and methyl isoplatydesmine (4) were isolated from the aerial parts of Skimmia laureola and their structures established by spectroscopic studies. Compounds 2-4 were found to be linear mixed type inhibitors of acetylcholinesterase (Ki = 110.0, 30.0 and 30.0 μM, respectively). Compounds 2 and 3 were also found to be linear mixed type inhibitors of butyrylcholinesterase, while compound 4 was a noncompetitive inhibitor of the enzyme (Ki = 90.0, 70.0 and 19.0 μM, respectively). The inhibition of acetyl- and butyryl-cholinesterase enzymes persists as the most promising therapeutic strategy for activating the impaired cholinergic functions in Alzheimer's disease and related dementias.Compound 4 also showed dose-dependent spasmolytic activity in the isolated rabbit jejunum intestinal preparation by relaxing the spontaneous (EC50 = 0.1 mg/mL) and K+-induced contractions (EC50 = 0.4 mg/mL), suggesting that the spasmolytic effect of compound 4 is mediated through the blockade of voltage-dependent Ca2 + channels. [ABSTRACT FROM AUTHOR]