Isolation of 20 Glycosides from the StarfishHenriciadowneyae, Collected in the Gulf of Mexico

Abstract

Thirteen new (1-13) and seven known (14-20) steroid glycosides were isolated from Henricia downeyae, collected from the offshore waters of the northern Gulf of Mexico. Ethanolic extracts of these starfish caused growth inhibition in bacteria and fungi, potent antifouling activity against barnacle and bryozoan larvae, and feeding deterrent activity against a marine fish. The known compounds are typical glycosides found in several species of the family Echinasteridae, i.e., Echinaster sp. and Henricia laeviuscola. One of the new compounds belongs to this group, whereas the remaining 12 new compounds represent a novel series of steroid glycosides which have aglycons with structural similarities to the "asterosaponins". They possess a delta 9(11) 3 beta, 6 alpha-dihydroxysteroidal aglycon with 23-oxo or 22,23-epoxy functionalities and often a 20-hydroxyl group in the side chain. The sulfate is located at C-6 and the saccharide moiety at C-3, in contrast with the asterosaponins which have the sulfate at C-3 and the oligosaccaride moiety at C-6. All the new compounds contain a glucuronic acid unit, which is uncommon among steroid glycosides from echinoderms. The structures of the new compounds, isolated in amounts ranging from 3.4 to 0.9 mg, were determined by interpretation of their spectral data and by comparison with spectral data of known compounds.

Chemical Constituents and Bioactivities of Starfish

“…Downeyosides A -L (377 -388, resp.) were obtained from Henricia downeyae collected in the northern Gulf of Mexico, and their structures were elucidated by spectral analysis [107] [108]. Two unusual sulfonylated polyhydroxylated steroid glucuronides, downeyosides A and B (377 and 378, resp.…”

“…The Caribbean starfish Echinaster brasiliensis yielded glycosides 406 -411 [111]. Desulfonylated 26-norechinasteroside A (412) was isolated from Henricia downeyae from the northern Gulf of Mexico [108]. Asteriidoside L (413), a moderately cytotoxic steroidal saponin, was isolated from an unidentified Antarctic starfish of the family Asteriidae [112].…”

Four new steroid glycosides from the Vietnamese starfish Linckia laevigata

“…Four new glycosides, which were called linckosides L3-L6 (1-4), nine previously known glycosides (5)(6)(7)(8)(9)(10)(11)(12)(13), and five previously known free polyhydroxysteroids (14)(15)(16)(17)(18) were isolated from these fractions by HPLC on semipreparative and analytical Diasfer 110 C18 columns. The results of chromatographic separation of extracted polar steroids are given in Table 1.…”

Cyclic Steroid Glycosides from the Starfish Echinaster luzonicus: Structures and Immunomodulatory Activities

“…3,10 The proton and carbon signals belonging to the side chain of 2 were derived from COSY, HSQC, HMBC, and ROESY experiments (Tables 1 and 2 …”

“…Comparison of the 1 H and 13 C NMR data of the aglycon moieties of glycosides 6 and 4 suggested that 6 has the same (20R)-23-oxo-cholestane side chain, and its aglycone differs from that of 4 only in the structure of ring B (Tables 1 and 2). The 1 H, 13 C, and DEPT NMR spectra of 6 contained signals for two angular Me groups CH [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]0.85;δ C 12.7,13.5), one methine group CH-3 (δ H 3.77, δ C 78.8) associated with oxygen, an α,β-unsaturated ketone [C-6 (δ C 202.4)], and a 7(8) double bond (δ H 5.65 (t, J = 2.2 Hz); δ C 123. 5, 166.7), encountered earlier in two steroids from starfish, i.e., asterasterols B and C. 14 The COSY, HSQC, ROESY, and HMBC cross-peaks supported the 3β-hydroxy-5α-cholest-7-en-6,23-dione as the aglycon moiety in 6 ( Figure 1C).…”