[Active constituents from Aloe arborescens as BACE inhibitors].

Aim: To seek for new components as BACE inhibitors from Aloe arborescens.
Methods: The chemical constituents were isolated by chromatographic methods and their structures were elucidated on the basis of spectral analysis.
Results: Eight compounds were isolated and their structures identified as 6'-O-isobutyryl aloenin A (1), aloenin A (2), aloe-emodin (3), (E)-2-acetonyl-8-(2'-O-feruloxyl)-beta-D-glucopyranosyl-7-methoxy-5-methyl-chromone (4), 7-O-methylaloeresin A (5), babarloin A (6), elgonica-dimer A (7), and elgonica-dimer B (8), separately.
Conclusion: Compound 1 is a new compound, and compound 4 was isolated from A. arborescens for the first time. Pharmacological tests indicated that 2, 4, 5 and 6 have moderate inhibitory active on BACE.