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ＣＨ ＿ Ｎ Ｅ５Ｅ口ＨＥＭ ＿ ＣＡ ＬCulcita novaeguineae, an abundant starfish distributed in South China Sea, showed significant cytotoxicity againstseveral human tumor cells. We have reported the isolation of 16 asterosaponins from this species [2,3]. Areinvestigation of the bioactive fraction led to the isolation of two new minor asterosaponins 1 and 2 structurallyrelated to novaeguinosides AandC [3]. They are the first andsecondexamples of24-hydroxylated asterosaponins, andshowed marginally cytotoxicity against human leukemia K-562 and hepatoma BEL-7402 cells (Fig. 1).Compound 1 was obtained as a colorless amorphous powder, ½a?Dwas established as C33H54O13S2Na2from the [M+Na]+ion at m/z 791.2701 in the positive HR-ESI-MS. Fragment ionsat m/z 671 [M+NaÀNaHSO4]+and 551 [M+NaÀ2 Â NaHSO4]+indicated the presence oftwo sulfate groups, and thefragment at m/z 543 [M+NaÀ248]+showed the loss ofa sulfated deoxyhexose unit. The data ofthe1H,13C NMR andDEPT spectra of1 suggested the presence ofa steroidal aglycone with a 9(11)-double bond (dH5.36; dC146.7, 117.7),one sulfated oxomethine (dH4.24; dC79.7) and two oxomethines (dH3.59, 3.24; dC81.0, 78.1). The assignment oftheＬ Ｅ Ｔ Ｔ ＥＲ ５doi:10.1016/j.cclet.2009.05.031Two new 24-hydroxylated asterosaponinsfrom Culcita novaeguineaeXiao Guang Maa,b, Hai Feng Tanga,*, Chang Hai Zhaoc,*,Ning Maa, Min Na Yaoa, Ai Dong WenaaDepartment ofPharmacy, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, ChinabHospital ofXi’an University ofFinance and Economics, Xi’an 710061, ChinacDepartment ofNutrition, Xijing Hospital, Fourth Military Medical University, Xi’an 710032, ChinaReceived 2 March 2009AbstractTwo new 24-hydroxylated asterosaponins, sodium (20R,24S)-6a-O-(4-O-sodiumsulfato-b-D-quinovopyranosyl)-5a-cholest-9(11)-en-3b,24-diol 3-sulfate (1) and sodium (20R,24S)-6a-O-[3-O-methyl-b-D-quinovopyranosyl-(1 ! 2)-b-D-xylopyranosyl-(1 ! 3)-b-D-glucopyranosyl]-5a-cholest-9(11)-en-3b,24-diol 3-sulfate (2), were isolated from the starfish Culcita novaeguineae.Their structures were elucidated by extensive spectral analysis and chemical evidences.# 2009 Hai Feng Tang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.Keywords: Starfish; Culcita novaeguineae; Steroidal glycoside; AsterosaponinSteroidal glycosides are the predominant metabolites of starfish and responsible for their general toxicity.Asterosaponins are characterized as sulfated steroidal penta- or hexaglycosides based on a D9(11)-3b,6a-dioxysteroidal aglycone with asulfate group attached at C-3 and the oligosaccharide moiety at C-6 [1]. In the course ofsearch for new anticancer compounds from echinoderms, we found that the total asterosaponin fraction prepared from20+9.1 (c 0.09, MeOH). Its molecular formulawww.elsevier.com/locate/ccletAvailable online at www.sciencedirect.comChinese Chemical Letters 20 (2009) 1227–1230* Corresponding authors.E-mail addresses: tanghaifeng71@163.com (H.F. Tang), natprod@163.com (C.H. Zhao).1001-8417/$ –see front matter # 2009 Hai Feng Tang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.万方数据