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Bioassay guided fractionation of the crude extract of Aloe vera L.has led to the isolation of chromone glucosides as beta-secretase inhibitors in our laboratory.In continuation of our research on the beta-secretase inhibitory agents from traditional Chinese medicine, we began to investigate Aloe arborescens.A.arborescens is a large, multi-stemmed shrub,which is widely distrubted in the Indian Ocean coast of southern Africa.A.arborescens has been prescribed as an emmenagogue, a febrifuge in pleurisy and phthisis, and as a remedy for gastrointestinal disorders, constipation, and bums in traditional Chinese medicine.It is also widely utilized in cosmetics and health food industry.As a result, two chromone glucosides 1 and 2, together with three other congeners 3, 4, and 5 were isolated.By the analysis of spectral data (UV, IR, El-MS, 1H and 13C NMR), their structures were characterised as (E)-2-acetonyl-8-(2-O-feruloyl-Dglucopyranosyl-7-methoxy-5-methylchromone 1, 7-O-methyl-aloeresin A 2, barbaloin 3, aloenin 4 and aloe-emodin 5, respectively.The chromone glucosides were isolated from this plant for the first time, and further chemical research and biological evaluation on the constituents of this herb are in progress.