Amarillidaceae species have attracted much attention of scientists around the world, due to their high content of alkaloids, mainly after that galanthamine was approved by the FDA as a drug for the treatment of Alzheimer's disease. Although galanthamine inhibits acetylcholinesterase, it causes a lot of side effects on patients that takes it [1 - 3]. Therefore, it is necessary the search and discovery of novel molecules with biological activities to extend and improve humans lives. With that in mind, the objective of this work was to isolate, purify, identify and characterize the alkaloids from Hippeastrum goianum, a Brazilian specie from the family Amarillidaceae, and further evaluate their cytotoxic activity. Bulbs of H. goianum were collected in Brasilia, in 2016. They were dried, crushed and extracted with MeOH, four times, at room temperature. Afterwards, the extract was submitted to the partition procedure, according to previous works [4], and three basic extracts were obtained from extractions with hexanes (HGC - 57,3 mg), ethyl acetate (HGD - 8,2 g) and ethyl acetate: methanol/3:1 (HGE - 9,2 g). After successive chromatographic fractionations of the HGD extract, five alkaloids were isolated (HGDA, HGDB, HGDC, HGDD and HGDE) and identified by 1D and 2D NMR spectroscopy. HGDA (306,0 mg) was identified as 7-deoxy-trans-dihydronarciclasine. Narciclasine derivatives usually show good biological activities [5]. Hence, HGDA was tested for cytotoxic activity against colorectal carcinoma (HCT-116), breast adenocarcinoma (MCF-7), melanoma (MM-200) and retinal pigment epithelium (RPE), presenting high cytotoxic potential with low half maximal inhibitory concentration (IC50) ranging from 0.15 μM in HCT-116 to 0.54 μM in MM200. HGDB was identified as 8-demethoxy-10-O-methylhostasine. This substance is a derivative of the homolycoline-type alkaloid, in which the B ring is five-membered, and was previously isolated only from Hosta plantaginea a specie from the family Liliaceae [6]. The alkaloids HGDC and HGDD were identified as lycorine and pseudolycorine, respectively. These two alkaloids are very common on Amarillidaceae species. HGDE was identified as 9-O-desmethyl-licoramine, which was isolated previously only from Lycoris radiata [7], but its NMR data were incomplete, so this work completes all the data. Accordingly, five alkaloids were isolated from H. goianum, being some of them not that common and with interesting skeletons and potential biological activities.

[1] Bastida, J., et al..Recent Advances in Pharmaceutical Sciences, 2011. p. 65-100.
[2] Wilcock, G.K., et al. BMJ, 2000. 321(7274): p. 1445.
[3] Wilkinson, D. & Murray, J.I. International J. of Geriatric Psychiatry, 2001. 16(9): p. 852-857.
[4] de Andrade, J. P., et al. J.Phytochemistry, 2014. 103: p. 188-195.
[5] Pettit, G.R., et al. Journal of natural products, 1993. 56(10): p. 1682-1687.
[6] Wang, Y. H.,et al. Journal of Natural Products,2007. 70(9): p. 1458-1461.
[7] Kobayashi, S., et al. Chemical Pharmaceutical Bulletin, 1980. 28(11): p. 3433-3436.