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Nine new steroids, stereonsteroids A-I (1-9), were isolated from the methylene chloride solubles of the Formosan soft coral Stereonephthya crystalliana Kükenthal. The structures were elucidated by extensive spectroscopic analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Three new steroidal saponins (1-3) were isolated from the roots of Smilax medica, together with the known disporoside A (4). The structures of the new compounds were elucidated mainly by extensive spectroscopic analysis (1D and 2D NMR, FABMS, and HRESIMS). Compounds 1, 2, and 4 demonstrated weak antifungal activity against the human pathogenic yeasts Candida albicans, C. glabrata, and C.tropicalis, with MIC values between 12.5 and 50 microg/mL.

The new cyclopropane-containing steroid phrygiasterol (1) and steroid glycoside phrygioside B (2), along with previously known borealoside C (2a) and (20R,24S)-5alpha-cholesta-3beta,6alpha,8,15alpha,24-pentaol (3), have been isolated from the Pacific starfish Hippasteria phrygiana. On the basis of spectroscopic analyses, using 1D and 2D NMR techniques and some chemical transformations, the structures of 1 and 2 have been established as (20R,24R,25R)-24,26-cyclo-5alpha-cholesta-3beta,6alpha,8,15alpha,16beta,27-hexaol (1) and the sodium salt of (20R,24S)-24-O-(3-O-methyl-4-O-sulfate-beta-d-xylopyranosyl)-5alpha-cholesta-3beta,6alpha,8,15alpha,24-pentaol (2), respectively. Compound 1 inhibited the growth of Ehrlich carcinoma cells with an IC(50) of 50 microg/mL, whereas 2 induced apoptosis of the same cells (EC(50)=70 microg/mL) and inhibited Ca(2+) influx into mouse spleenocytes (EC(50)=20microg/mL).

Six new polyoxygenated steroids, hippuristerones J-L (1-3), hippuristerols E-F (4, 5), and a novel gorgosteroid, 1alpha,3beta,5beta,11alpha-tetrahydroxygorgostan-6-one (6), were isolated from the gorgonian Isis hippuris. The structures of these metabolites were elucidated by extensive spectroscopic analyses and comparison of the NMR data with those of related steroids.

It has been demonstrated that liver X receptors (LXR) play a significant role in cholesterol homeostasis. Agonists of LXR are expected to increase cellular cholesterol efflux, lower LDL, and raise HDL levels. Screening of a natural product library of plant extracts using a LXR-SPA binding assay and bioassay-guided fractionation of a number of plant and marine gorgonian extracts led to the isolation of a number of active compounds. These included acanthoic acid (1) and alcohol (2), viperidone (3), polycarpol (4), rosacea acid (5), a cycloartane derivative (6), a new cycloartane analogue (7), betulinic acid (8), and gorgostane derivatives (9, 10, and 11). Of these compounds, 1, 4, and 11 exhibited potent binding affinity for alpha-receptor with IC(50) values of 0.25, 0.12, and 0.07 microM, respectively. Functionally they also showed strong coactivator association stimulation for LXRalpha receptor with EC50 values of 0.18, 0.03, and 0.05 microM, respectively. They also exhibited 15-, 8-, and 13-fold induction of the alpha-receptor in a transactivation assay in HEK-293 cells, respectively. In general these compounds were selective for the LXR alpha-receptor over the beta-receptor in all assays and were much better stimulators of the alpha-receptor than the endogenous steroid ligands.

Two new sulfated polyhydroxylated steroidal xylosides, minutosides A (1) and B (2), together with the known pycnopodioside B (3), have been isolated from the brine shrimp active fraction of the ethanolic extract of the starfish Anasterias minuta. The structures have been elucidated by extensive 1D and 2D NMR as well as FABMS analysis and chemical methods. Compound 2 is the first example of a polyhydroxylated steroidal xyloside containing an amide function in the aglycon side chain. The three xylosides exhibited antifungal activity against Cladosporium cucumerinum and Aspergillus flavus.

Seven new steroids, compounds 1-7, were isolated from the Antarctic octocoral Anthomastus bathyproctus. The structures of the new metabolites have been established by analysis of their spectroscopic data. The in vitro cytotoxicity has been tested against three human tumor cell lines.

Eleven new hippuristanols (1-4, 7-9, and 11-14), along with eight known metabolites (5, 6, 10, and 15-19), have been isolated from the gorgonian coral Isis hippuris. Single-crystal X-ray diffraction analyses supported the structure elucidation of known steroids 5 and 10. The absolute structures of hippuristanols were established by application of modified Mosher's method on 19. Compounds 14-19 have been found to exhibit significant cytotoxicity against several cancer cell lines.

Four new steroidal alkaloids, puqienine A (1), puqienine B (2), N-demethylpuqietinone (3), and puqietinonoside (4), along with a known steroidal alkaloid, puqietinone, were isolated from the bulbs of Fritillaria puqiensis. The structures of these compounds were elucidated on the basis of spectroscopic analysis. The compounds exhibited significant antitussive activity on ammonia liquor-induced cough in mice. Furthermore, the compounds were evaluated for activities against A549 human lung carcinoma cell line, BGC-823 human stomach adenocarcinoma cell line, SMMC-7721 human hepatocarcinoma cell line, and HL-60 human promyelocytic leukemia cell line.

Two novel cholic acid derivatives and three known steroids were isolated from an octocoral Eleutherobiasp. from Pohnpei Micronesia along with the known briareins minabein-1 (6), minabein-4 (7), minabein-6 (8), minabein-8 (9), and minabein-9 (10). X-ray crystallographic analysis of the known compound minabein-4 allowed assignment of its correct relative and absolute stereochemistry. Consequently, a different structure proposed for the same compound (named independently as nui-inoalide-D) is incorrect.

The identification of aromatic steroid hydrocarbons bearing a methyl group at positions 1, 2, 3, 4, or 6 in sediments and petroleum has been puzzling since possible steroidal precursors have not yet been reported in living organisms. Two new aromatic steroids, (17beta,20R,22E,24R)-19-norergosta-1,3,5,7,9,14,22-heptaene (1) and (17beta,20R,22E,24R)-1-methyl-19-norergosta-1,3,5,7,9,14,22-heptaene (2), were isolated from the ascomycete Daldinia concentrica, of which compound 2 bears an unusual methyl group at position 1. We propose that the origin of these compounds is derived from the transformation undergone by their precursor due to microbial action. Compounds 1 and 2 could be the long-sought, biological precursor steroids for organic matter in Earth's subsurface.

Four new steroids, acanthovagasteroids A-D (1-4), along with two known analogues (5, 6), were isolated from the gorgonian Acanthogorgia vagae Aurivillius from the South China Sea. The structures of the new compounds, characterized with 19-hydroxy groups, were identified on the basis of extensive spectral analysis as well as by comparison with literature data. This is the first report of 19-hydroxy steroids from a gorgonian and suggests a possible biosynthetic relationship between 19-nor and 19-hydroxy steroids.

Four new steroidal saponins, polygonatosides A-D (1-4), were isolated from the rhizomes of Polygonatum zanlanscianense, together with six known spirostanols (5-10) and a known megastigmane glycoside (11). Their structures were elucidated on the basis of spectroscopic analysis and the results of acidic and enzymatic hydrolysis. The cytotoxic activities of 1-11 against HeLa cells are described.

One new cytotoxic steroid, dendronesterone A (1), two new steroids, dendronesterones B and C (2 and 3), and a known steroid (4) were isolated from the methylene chloride solubles of the Formosan soft coral Dendronephthya gigantea. Two cytotoxic ylangene-type sesquiterpenoids, lemnalol (5) and the new compound cervicol (6), as well as two ylangene-type sesquiterpenoids, isolemnalol (7) (a new compound) and 4-oxo-alpha-ylangene (8), were isolated from the methylene chloride solubles of the Formosan soft coral Lemnalia cervicorni. Their structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Phytochemical analyses have been carried out on the fresh bulbs of Ornithogalum thyrsoides with particular attention to the steroidal glycoside constituents, resulting in the isolation of four new spirostanol saponins and seven new cholestane glycosides, together with three known steroidal compounds. The structures of the new glycosides were determined on the basis of their spectroscopic data, including 2D NMR spectroscopy, and the results of hydrolytic cleavage. The isolated compounds were evaluated for their cytotoxic activities against HL-60 human promyelocytic leukemia cells and HSC-2 human oral squamous cell carcinoma cells.

The sponge Phorbas amaranthus from Florida contains the new ring A-contracted steroids, phorbasterones A-D, and the known anthosterones A and B. The structures of phorbasterones A-D were determined by interpretation of their spectroscopic data. Phorbasterones show moderate cytotoxicity against HCT-116 tumor cells.

Three new steroidal alkaloid glycosides, lycoperosides F-H (1-3), were isolated from tomato fruits (Lycopersicon sculentum) along with lycoperosides A-D, esculeoside A, and rutin. The structures of these glycosides were characterized as the 3-O-beta-lycotetraosides of 23(R)-23-acetoxy-27-hydroxy-27-O-beta-d-glucopyranosyltomatidine (1), (23S,24R)-23-acetoxy-24-O-beta-d-glucopyranosylsoladulcidine-24-ol (2), and 22-isopimpifolidine (3), by means of their spectroscopic data. Also obtained was the new natural product lycoperodine-1 (4).

Four new triterpenoids, tyromycic acids B-E (1-4), were isolated from a methanol-soluble extract of the fruit bodies of the Japanese inedible mushroom Tyromyces fissilis. Tyromycic acids B-D possess a lanostane skeleton, while tyromycic acid E is based on a rare 14(13-->12)abeo-lanostane skeleton. Their structures were determined by spectral data analysis and by single-crystal X-ray crystallography.

Two new C-21 steroidal glycoside epimers, paniculatumosides A and B (1 and 2), based on a 13,14:14,15-disecopregnane-type skeleton, with neocynapanogenin B (3) and neocynapanogenin C (4) as two new aglycons, were isolated from the roots of Cynanchum paniculatum. Their structures were determined by spectral data interpretation.

Four new steroidal alkaloids, plakinamine I-K (1-3) and dihydroplakinamine K (4), were isolated from the marine sponge Corticium niger. The structures of these compounds were elucidated by interpretation of spectroscopic data. Compounds 1-4 exhibit significant in vitro cytotoxicity.

New steroidal oligoglycosides mycalosides B-I (2-9) have been isolated from the polar extract of the Caribbean sponge Mycale laxissima, and their structures have been elucidated by 1D and 2D NMR ((1)H, (13)C, DEPT, COSY-45, COSY-RCT, HSQC, HMBC, and NOESY spectra) and MALDI-TOF mass spectrometry. Mycalosides B (2) and C (3) were shown to be 27- and 28-nor derivatives of the previously known tetraoside mycaloside A (1). Mycaloside D (4) differs from 1 only in the presence of an additional acetyl group in the carbohydrate moiety. Mycaloside E (5) was structurally identified as a 28-nor-4-dehydroxy derivative of 1. Mycalosides F-H (6-8), differing from each other by the structures of their side chains and nonacetylated (7, 8) or acetylated (6) tetrasaccharide carbohydrate moieties, have new 5(6)-unsaturated 3 beta,4 beta,21-trihydroxy-15-keto-steroidal aglycons. Mycaloside I (9) is a tetraoside of a new 7,24(28)-diunsaturated 3beta,15 beta,29-trihydroxystigmastane aglycon. It was established that the total fraction of the mycalosides as well as mycalosides A (1) and G (7) inhibit the fertilization of eggs by sperm of the sea urchin Strongylocentrotus nudus preincubated with these compounds.

Five novel (22R,23S,24S)-steroids, hippuristerones E-I (1-5), have been isolated from the gorgonian coral Isis hippuris. The structures of steroids 1-5 were deduced by extensive 1D and 2D NMR studies ((1)H, (13)C, (1)H-(1)H COSY, HMQC, HMBC, and NOESY experiments). The structure of 1 was further supported by molecular mechanics calculations.

Two new withanolide glucosides, chantriolides A (1) and B (2), were isolated from the rhizomes of Tacca chantrieri. Their structures were determined on the basis of extensive spectroscopic studies and by acid hydrolysis as (22R)-1alpha,12alpha-diacetoxy-2alpha,3alpha;6alpha,7alpha-diepoxy-27-[(beta-d-glucopyranosyl)oxy]-5alpha-hydroxy-16-oxowith-24-enolide (1) and (22R)-1alpha,12alpha-diacetoxy-2alpha,3alpha;6alpha,7alpha-diepoxy-27-[(beta-d-glucopyranosyl)oxy]-5alpha,16beta-dihydroxywith-24-enolide (2), respectively. It is notable that withanolides, which have been almost exclusively isolated from plants of the family Solanaceae to date, have been found in a species in the family Taccaceae in the present study.

From the stem bark of Dracaena draco, three new compounds, namely, draconins A-C (1-3), were isolated, along with 17 known compounds. The structures of the new compounds isolated were elucidated on the basis of spectroscopic data interpretation. Several of the isolated compounds showed potent cytotoxic activities measured on the human leukemia cell line HL-60 (IC(50)'s from 2.0 to 9.7 microM at 72 h). The mechanism by which compounds 1 and 2 display their cytostatic properties is through induction of cell death by apoptosis, as evaluated by fluorescence microscopy and DNA fragmentation.

Four new 5alpha-steroidal glycosides with an unusual framework, funingenosides A (1), B (2), C (3), and D (4), were isolated from the roots of Parepigynum funingense. Their structures were elucidated on the basis of 1D and 2D NMR techniques. The structure and relative stereochemistry of compound 1 were demonstrated by X-ray crystallographic analysis.

An investigation of the polar extracts from two starfish, Luidia quinaria and Psilaster cassiope, led to the isolation of five sulfated "asterosaponins". Two of them, named luidiaquinoside (1) and psilasteroside (2), are new compounds. Luidiaquinoside (1) contains a novel pentasaccharide chain composed of d-glucose, d-quinovose, and d-fucose, with the d-glucose unit being the branching point. Psilasteroside (2) contains a hexasaccharide chain in which an arabinose residue is detectable in the furanose form. Both of these compounds possess a Delta(9(11)),3beta,6alpha-dihydroxysteroidal nucleus with a 20-hydroxy, 23-oxo functionality. The structures of the new asterosaponins were elucidated by a combination of NMR techniques including (1)H-(1)H (COSY, TOCSY, and ROESY) and (1)H-(13)C (HMQC and HMBC) spectroscopy, ESIMS and HRFABMS spectrometry, and GC analyses. The new asterosaponins show marginal in vitro cytotoxicity against RBL-2H3 (rat basophilic leukemia) cell lines.

Four compounds, daldinone A (1), daldinone B (2), daldiniapyrone (4-methoxy-5-carbomethoxy-6-pentyl-2H-pyran-2-one, 3), and daldinialanone (22R-hydroxylanosta-7,9(11),24-trien-3-one, 4), were isolated from an ethyl acetate extract of fruit bodies of Daldinia concentrica collected in Europe. In addition, 11 known compounds, 4:5:4':5'-tetrahydroxy-1:1'-binaphthyl (5), 3,4,5-trihydroxy-1-tetralone (6), (+)-orthosporin (7), curuilignan D (8), (22E)-cholesta-4,6,8(14),22-tetraen-3-one (9), 3beta,22-dihydroxylanosta-7,9(11),24-triene (10), concentricol (11), concentricol B (12), concentricol C (13), concentricol D (14), and phenochalasin B (15), were obtained. The structures of the new compounds were elucidated by 2D NMR, MS, IR, and UV spectra and by X-ray crystallographic analysis. The absolute configurations of 1 and 4 were determined by CD spectroscopy and the modified Mosher's method, respectively. The chemotaxonomic relevance of the compounds obtained in this investigation is discussed.

Further phytochemical analysis aimed at the steroidal glycoside constituents of the leaves of Cestrum nocturnum has resulted in the isolation of eight new steroidal glycosides (1-8), which were classified into a spirostanol saponin (1), a furostanol saponin (2), a pseudo-furostanol saponin (3), two pregnane glycosides (4, 5), two cholestane glycosides (6, 7), and pregnane-carboxylic acid gamma-lactone glycoside (8), and of two known spirostanol glycosides (9, 10). The structures of the new compounds were elucidated on the basis of chemical and spectroscopic evidence.

Four new steroidal saponins, anguiviosides III (1), XI (2), XV (3), and XVI (4), were isolated and characterized from the fruits of Solanum anguivi. Their structures were elucidated on the basis of spectroscopic analysis. The occurrence of the cholestane glycosides 3 and 4 is considered from a biogenetic point of view.

Three new cytotoxic prostanoids, claviridenone E-G (1-3), and three new cytotoxic steroids, stoloniferone E-G (4-6), were isolated from the methylene chloride solubles of the Formosan soft coral Clavulariaviridis. A cytotoxic cembranoid, claviolide (7), was isolated from the methylene chloride solubles of the Formosan soft coral Clavularia violacea. The structures were elucidated by 1D and 2D NMR spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.

Three new polyoxygenated steroids, nanjiol A (1), B (2), and C (3), were isolated from an East China Sea soft coral Nephthea bayeri, and their structures were characterized by spectroscopic methods and comparison with known compounds. The new molecules were structurally related to (20S)-cholesta-1,4-diene-18,20-diol-3-one (4), a typical metabolite from the black coral Antipathes subpinnata.

A rapid semi-homogeneous cyclooxygenase-2 (COX-2) enzymatic assay using scintillation proximity assay (SPA) technology was developed, and 49 ubiquitous plant secondary metabolites were screened for inhibition of COX-2-catalyzed prostaglandin E(2) (PGE(2)) biosynthesis. Assay conditions were optimized with respect to reaction time, amount of antibody, radiolabeled PGE(2), and SPA beads, and the kinetic parameter, K(m), was estimated. The assay was validated with two natural triterpenoids, ursolic and oleanolic acid, known to inhibit COX-2, as well as with four synthetic COX inhibitors, NS-398, rofecoxib, indomethacin, and aspirin. Plant metabolites of different biosynthetic origin representing several substance classes, including alkaloids, anthraquinones, flavonoids, phenylpropanes, steroids, and terpenes, were screened for inhibition of COX-2-catalyzed PGE(2) production. Of these 49 plant metabolites, eugenol, pyrogallol, and cinnamaldehyde (with IC(50) values of 129, 144, and 245 microM, respectively) were found to inhibit COX-2. This study showed that a COX-2-catalyzed PGE(2) assay using SPA is suitable for screening natural compounds with respect to COX-2 inhibition.

Ten new saponins designated as certonardosides A-J (1-5, 7-11) and the known halityloside D (6) were isolated from the brine shrimp active fraction of the MeOH extract of the starfish Certonardoa semiregularis. The structures were determined on the basis of spectral analysis and chemical manipulation. The compounds were evaluated for antiviral activity against HIV, HSV, CoxB, EMCV, and VSV and displayed insignificant activity within the range of noncytotoxic concentrations.

The rhizomes of Tacca chantrieri have been analyzed as part of a systematic study on saponin constituents of medicinal plants. This has resulted in the isolation of three new bisdesmosidic furostanol saponins (1-3), two new bisdesmosidic pseudofurostanol saponins (4, 5), and two new pregnane glycosides (6, 7). Their structures were determined on the basis of extensive spectroscopic studies and a few chemical transformations.

Four new steroidal alkaloids, plakinamine G (1), plakinamine H (2), 4alpha-hydroxydemethylplakinamine B (3), and tetrahydroplakinamine A (4), along with three known compounds, were isolated from the marine sponge Corticium sp. The structures of these metabolites were elucidated largely by 1D and 2D NMR methods and accurate mass measurements (HR-EIMS). Compounds 1, 2, and 4 show significant in vitro cytotoxicity.

Thirty-seven naturally occurring withanolides (1-37), previously isolated in our laboratories, were evaluated for their potential to induce quinone reductase with cultured murine hepatoma cells (Hepa 1c1c7). Spiranoid (29, 32) and 18-functionalized withanolides (2-5, 7-9, 24) were found to be potent inducers of the enzyme, while 5alpha-substituted derivatives exhibited weak activity. Preliminary studies were performed with compound 29 to evaluate enzyme-inducing capacity in multiple organ sites of BALB/c mice. Significant induction was observed in liver and colon, but not in lung, stomach, or mammary gland.

Clathriol (1), a highly oxygenated steroid with the unusual 14beta configuration, was isolated from the New Zealand marine sponge Clathria lissosclera. The structure was elucidated from a combination of NMR and mass spectroscopy. Clathriol showed in vitro antiinflammatory activity against human neutrophyl and rat mast cells.

Two new steroidal alkaloids, along with a previously reported one of the plakinamine class, were isolated from the sponge Corticium sp. collected from Guam. The structures of the new compounds were determined by combined spectroscopic methods. These compounds exhibited moderate cytotoxicity and antifungal activity as well as DNA- and RNA-cleaving activities.

Two novel steroidal 24-O-xylosides, designated as rathbuniosides R(1) (1) and R(2) (2), and the known amurensoside A (3) and 3-O-sulfomarthasterone (4) have been isolated from the starfish Asterias rathbuni. The structures of all the compounds were determined from their spectroscopic data, including one- and two-dimensional NMR methods. The compounds 1 and 4 inhibit the cell division of fertilized sea urchin eggs at doses of 7.0 x 10(-5) and 2.9 x 10(-5) M, respectively.

Two novel steroids with a cyclopropane ring at C-25 and C-26, 7-oxopetrosterol (1) and 7alpha-hydroxypetrosterol (2), along with two known compounds, petrosterol (3) and 23,24-dihydrocalysterol (4), have been isolated from the Japanese marine sponge Strongylophora corticata. The structures of 1 and 2 were determined as 26, 27-cyclo-24,27-dimethyl-3beta-hydroxycholest-5-en-7-one and 26, 27-cyclo-24,27-dimethylcholest-5-en-3beta,7alpha-diol on the basis of spectroscopic investigations.

A chemical investigation of the aerial parts of Polianthes tuberosa resulted in the isolation of a new bisdesmosidic cholestane glycoside (1) and three new spirostanol saponins (2-4), along with a known cholestane glycoside. The structures of new glycosides were determined by spectroscopic analysis, including 2D NMR spectroscopic data, and the results of hydrolytic cleavage. The isolated compounds were evaluated for their cytotoxic activity on HL-60 human promyelocytic leukemia cells.

Two novel steroids, polasterol A (1) and polasterol B sulfate (2), along with two known compounds, 22(E),24-isopropylcholesta-5, 22-dien-3 beta-ol (3) and halistanol sulfate (4), have been isolated from the Japanese marine sponge Epipolasis sp. The structures of 1 and 2 were determined as 3 beta-hydroxy-24-isopropylcholesta-5, 22(E)-dien-7-one and 24xi-isopropenylcholesta-22(Z), 28(29)-diene-2 beta,3 alpha,6 alpha-triyl trisodium sulfate on the basis of spectroscopic investigations and a chemical conversion.

A reinvestigation of the polar steroid fraction from the starfish Aphelasterias japonica, collected near the Russian shore of the Sea of Japan, has afforded two new compounds, the disulfated quinovoside aphelasteroside C (1) and the monosulfated polyhydroxysteroid aphelaketotriol (2). Compounds 1 and 2 contain a unique 23-oxo-24-hydroxylated side chain that is unprecedented in marine steroids. The known compounds cheliferoside L1 (3), 3-O-sulfoasterone (4), forbeside E3 (5), and 3-O-sulfothornasterol A (6) were also isolated from this source. Compounds 1-3, 5, and 6 showed hemolytic activity to mouse erythrocytes.

A detailed further examination of the Indian Ocean soft coral Sarcophyton crassocaule resulted in the isolation of altogether 17 compounds of which two (1 and 2) are novel 17beta,20beta-epoxy steroids and one is a new dihydroxygorgost-5-en (3). The other compounds include the four hippurin steroids (4-7) reported earlier, and some known derivatives such as methyl arachidonate, batyl alcohol, a mixture of monohydroxy sterols, 3beta-hydroxypregn-5-en-20-one, two prostaglandin derivatives (PGB(2) acid and its methyl ester), and 9-oxo-9, 11-secogorgost-5-ene-3beta,11-diol (8). The structure of new dihydroxygorgostene derivative was established as gorgost-5-ene-3beta,11alpha-diol (3), while the structures of the novel epoxy steroids were established as 17beta,20beta-epoxy-23, 24-dimethylcholest-5-ene-3beta,22-diol (2) and its 3beta, 22-diacetate (1), respectively.

Three new ergostane-type steroids, 3beta-hydroxy-4alpha, 14alpha-dimethyl-5alpha-ergosta-8,24(28)-dien-11 -one (1); 3beta, 11alpha-dihydroxy-4alpha,14alpha-dimethyl-5alpha -ergosta-8, 24(28)-dien-7-one (2); and 3beta,7alpha-dihydroxy-4alpha, 14alpha-dimethyl-5alpha-ergosta-8,24(28)-dien-11 -one (3), were isolated, together with two known triterpenoids, wrightial and lup-20(30)-ene-3beta,29-diol from the whole herb of Euphorbia chamaesyce. Compound 3 showed a potent inhibitory effect on Epstein-Barr virus early antigen activation induced by the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA).

Two new cardenolides, 3beta-hydroxy-5alpha-carda-14(15), 20(22)-dienolide (beta-anhydroepidigitoxigenin) (1) and 3beta-O-(D-digitalosyl)-21-hydroxy-5beta-carda-8,14,16 , 20(22)-tetraenolide (neriumogenin-A-3beta-D-digitaloside) (2), and two known compounds, proceragenin and neridienone A (3), have been isolated from the roots of Nerium oleander. The structures of 1 and 2 were elucidated on the basis of spectral data interpretation.

The EtOH extract of the leaves of Holarrhena curtisii yielded five new steroidal alkaloids: 17-epi-holacurtine (3), 17-epi-N-demethylholacurtine (4), holacurtinol (5), 3alpha-amino-14beta-hydroxypregnan-20-one (7), and 15alpha-hydroxyholamine (8), in addition to the known compounds, holacurtine (1), N-demethylholacurtine (2), and holamine (6). All eight compounds showed significant cytotoxic and leishmanicidal activities.

Ten new steroidal sulfates, acanthosterol sulfates A-J (1-10), have been isolated from a marine sponge, Acanthodendrilla sp., collected in western Japan. Acanthosterol sulfates I and J (9 and 10) showed antifungal activity against the yeast Saccharomyces cerevisiae A364A and its mutants at 0.1 mg/disk.

A new saponin possessing a pregnene-derived aglycon (1) has been isolated from the Caribbean gorgonian octocoral Eunicea sp. The structure of the new compound was assigned on the basis of chemical and spectral studies.

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.