Salacia crassifolia traditionally known as "Bacupari-do-Cerrado" is used to treat kidney problems, and as a healing agent for coughs and malaria. The phytochemical study of the S. crassifolia roots led to the isolation of thirteen compounds: abruslactone-A (1), urs-12-ene-3β,25,30-triol (2), carioprystimerin (3), β-sitosterol (4), pristimerin (5), dispermoquinone (6), netzahualcoyonol (7), 20-hydroxy-20-epi-tingenone (8), 6-oxo-pristimerol (9), 9β,10β-epoxi-3β-hydroxy-1βH,4βH,5βH,7βH,11αH-guaian-12,8β-olide (10), 3-O-β-D-glucosyl-β-sitosterol (11), 4`-O-methylepigalocatechin (12) and cerebroside (13). The chemical structures of 1-13 were determined by IR, 1D/2D NMR together with X-ray diffractometry. Compounds 2 and 10 are herein described for the first time. Extracts of S. crassifolia and compounds 3, 5, 8 and 9 were evaluated on acetylcholinesterase inhibition, in vitro cytotoxic activity and in vivo toxicity tests using Caenorhabditis elegans model. All tested compounds inhibited acetylcholinesterase, and compounds 3, 8 and 9 demonstrated a greater potential when compared to the standard eserine. The tested compounds showed low cytotoxicity against the THP-1, K562 and MDA-MB-231 cancer cell lines. None of the tested compounds and extracts were toxic against C. elegans since the larvae survival rate in L1 stage was higher than 90%.