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F Zollo

Publications and source records attributed to F Zollo.

9 recordsLinked to original sources
PubMed1998

Starfish saponins. 55. Isolation, structure elucidation, and biological activity of the steroid oligoglycosides from an Antarctic starfish of the family Asteriidae.

This paper reports an analysis of the chemical constituents from an Antarctic starfish of the family Asteriidae. Different steroid glycoside types are represented among its constituents, including the five hexaglycoside steroidal sulfates ("asterosaponins") asteriidosides A-E (1-5), differing in their oligosaccharide chain, and the two nonsulfated diglycosides asteriidoside F (6) and G (7), in which 6 is the 26-methyl analogue of 7. Also present are the two sulfated diglycosides asteriidoside H (8) and I (9) and one sulfated monoglycoside asteriidoside L (10). Eight of the compounds were tested against human nonsmall-cell lung carcinoma cells (NSCLC-L16) and found to be moderately cytotoxic.

Animals↗
PubMed1997

Isolation, structure elucidation, and biological activity of the steroid oligoglycosides and polyhydroxysteroids from the Antarctic starfish Acodontaster conspicuus.

A total of 19 steroids, of which 13 steroidal oligoglycosides (nine new and four known) and six polyhydroxylated steroids (four new and two known), has been isolated from the Antarctic starfish Acodontaster conspicuus. The mixture is dominated by glycosides composed of steroidal aglycons having the hydroxyl groups typically disposed on one side of the tetracyclic nucleus, i.e., 3 beta,4 beta,6 alpha,8,15 beta-, with some having a sulfate at C-6, and differing in the side chains and/or in the disaccharide moieties that are usually attached at C-26, with some at C-28 and C-29. Those compounds are accompanied by minute amounts of glycosides with a delta 8(14)-double bond in the steroid, which is a structural feature not previously found among polyhydroxysteroids derived from starfish. Small amounts of six related unglycosidated polyhydroxysteroids and three higher-molecular-weight asterosaponins complete the composition of the mixture. The structures of the new compounds were determined by interpretation of their spectral data and by comparison with spectral data of known compounds. Eighteen of these compounds were evaluated for their ability to inhibit growth in Antarctic marine bacteria isolated from either the water column or the surfaces of benthic marine invertebrates. Of these compounds, 50% were active against at least one Antarctic marine bacterium. This suggests that these compounds may play an important role in deterring microbial fouling.

Animals↗
PubMed1996

Isolation of 20 glycosides from the starfish Henricia downeyae, collected in the Gulf of Mexico.

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.

Animals↗
PubMed1995

Starfish saponins, Part 53. A reinvestigation of the polar steroids from the starfish Oreaster reticulatus: isolation of sixteen steroidal oligoglycosides and six polyhydroxysteroids.

A reinvestigation of the starfish Oreaster reticulatus has led to the isolation of sixteen steroidal oligoglycosides and six polyhydroxysteroids. One steroidal monoglycoside has been identified as asterosaponin-1 [5], previously isolated from the same organism, and one pentaglycoside steroidal sulfate has been identified with the known ophidianoside F [1], previously isolated from starfish species of the family Ophidiasteridae. The novel pentaglycoside steroidal sulfates reticulatosides A [3] and B [4] represent the second examples of asterosaponins containing the 5 alpha-cholesta-9(11)-en-3 beta,6 alpha,20,22-tetraol aglycone. Of the remaining new steroidal oligoglycosides, the majority are characterized by the common (24S)-5 alpha-cholesta-3 beta,6 alpha,8,15 alpha,24-pentaol aglycone, with some having a sulfate group at C-6, and differing in the sugar moiety. Compounds 11, 12, 15, and 16 represent major departures from the more common structural features encountered in steroidal glycosides from starfish with the presence in 11 and 12 of a rare 5-O-methylgalactofuranosyl unit and in 15 and 16 of a 3-O-methyl-2-O-sulfate-xylopyranosyl unit. The latter was shown by nmr data combined with molecular dynamics calculations to exist in an 8:2 equilibrium mixture of the 1C4 and 4C1 conformations.

Animals↗
PubMed1995

Chemical and biological investigation of the polar constituents of the starfish Luidia clathrata, collected in the Gulf of Mexico.

Ten new [1-10] and three known [11-13] polyhydroxysteroids were isolated, along with four known asterosaponins [14-17], from the starfish Luidia clathrata, collected from the offshore waters of the northern Gulf of Mexico. The EtOH extracts of this starfish showed feeding-deterrent properties against marine fish, and inhibited the settlement of larvae of barnacles and bryozoans, as well as the growth of several bacteria. The structures of the new compounds were determined by interpretation of their nmr spectral data and by comparison with the spectral data of known compounds. The assignment of the configurations of the side-chain stereogenic centers of compounds 1 and 3-10 were based on the comparison of their nmr data with those of the stereoisomeric model compounds after derivatization with the chiral auxiliary MTPA reagent. Larval settlement assays conducted on ten isolated compounds revealed they are all potent inhibitors of settlement. Two of these isolated compounds inhibited the growth of several bacteria.

Animals↗
PubMed1994

Four new dimeric peptide alkaloids, anchinopeptolides B-D, and cycloanchinopeptolide C, congeners of anchinopeptolide A, from the Mediterranean marine sponge Anchinoe tenacior.

Following the characterization of anchinopeptolide A[1], three new congeneric dimeric peptide alkaloids, named anchinopeptolides B [2], C[3], and D[4], have been isolated from the Mediterranean sponge Anchinoe tenacior. A fourth compound, cycloanchinopeptolide C[5], which is related to anchinopeptolide C[3] by a head-to-head intramolecular [2+2] cyclo-addition reaction, has also been isolated. The structures of these peptide alkaloids have been elucidated on the basis of spectral evidence. Anchinopeptolides bind to the somatostatin, human B2 bradykinin, and neuropeptide Y receptors.

Alkaloids↗
PubMed1993

Starfish saponins, part 49. New cytotoxic steroidal glycosides from the starfish Fromia monilis.

Nine new cytotoxic steroidal glycosides 1-9 have been isolated from the starfish Fromia monilis collected off New Caledonia. Structures of these compounds, which include four mono-(1-4), two di-(5,6), and three glycosides (7-9), were elucidated through spectral interpretation. Monilosides G [7], H [8], and I [9] are the first tri-glycosides to be found among the group of glycosides of polyhydroxilated steroids from starfishes.

Animals↗
PubMed1993

Paniceins and related sesquiterpenoids from the Mediterranean sponge Reniera fulva.

Two novel sesquiterpenes, fulvanin 1 [1] and fulvanin 2 [2], have been isolated from the Mediterranean sponge Reniera fulva. Compound 2 is a sesquiterpenoid linked to a hydroquinone. Also found in Reniera fulva are four known paniceins, a group of aromatic sesquiterpenoids linked to a quinol, isolated previously from Halichondria panicea. The total assignments of 13C-nmr spectra of paniceins have been made with the aid of 2D1H-13C correlation techniques, confirming their structures. The paniceins were tested in the in vitro disease-oriented primary antitumor screen at NCI, Bethesda. Paniceins C and B3 showed cytotoxicity against NCI-H522 non-small lung cancer cells and CCRF-CEM leukemia cells, while panicein A hydroquinone revealed more selective cytotoxicity against the latter ones.

Animals↗