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The genus Polygonatum Mill. belongs to the Liliaceae family, which is widely distributed all over the world. Modern studies have found that Polygonatum plants are very rich in chemical compounds such as saponins, polysaccharides and flavonoids. Steroidal saponins are the most commonly studied saponins in the genus Polygonatum and a total of 156 compounds have been isolated from 10 species of the genus. These molecules possess antitumor, immunoregulatory, anti-inflammatory, antibacterial, antiviral, hypoglycemic, lipid-lowering and anti-osteoporotic activities. In this review, we summarize recent advances in studies of the chemical constituents of steroidal saponins from Polygonatum, including their structural characteristics, possible biosynthetic pathways and pharmacological effects. Then, the relationship between the structure and some physiological activities is considered. This review aims to provide reference for further exploitation and utilization of the genus Polygonatum., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Eight undescribed ergostane-type steroids, (22E,24R)-ergosta-7,22-dien-3β,5α-diol- 6,5-olide, (22E,24R)-ergosta-7,9(11),22-trien-3β,5β,6β-triol, (22E,24R)-6β-methoxy ergosta-7,9(11),22-trien-3β,5α,14β-triol, (22E,24R)-9α,15α-dihydroxyergosta-4,6,8 (14),22-tetraen-3-one, (22E,24R)-ergosta-5,8,22-trien-3β,11α-dihydroxyl-7-one, (22E,24R)-ergosta-4,7,22-trien-3β,9α,14β-trihydroxyl-6-one, (22E,24R)-ergosta-7,22- dien-3β,9α,14β-trihydroxyl-6-one, and (22E,24R)-6β-methoxyergosta-7,22-dien-3β, 5α,9α,14β-tetraol, and twenty-one known analogues were isolated from the fruiting bodies of Ganoderma resinaceum Boud. Their chemical structures were determined on the basis of comprehensive spectroscopic analysis and X-ray crystal diffraction, as well as empirical pyridine-induced deshielding effects. Furthermore, selected compounds were evaluated for their inhibitory effects on macrophage activation using an inhibition of nitric oxide production assay. Finally, (22E,24R)-ergosta-5,8,22- trien-3β,11α-dihydroxyl-7-one, (22E,24R)-ergosta-4,7,22-trien-3β,9α,14β-tri hydroxyl-6-one, (22E,24R)-6β-methoxyergosta-7,22-dien-3β,5α,9α,14β-tetraol, (22E,24R)-ergosta-6,9,22-trien-3β,5α,8α-triol,ergost-6,22-dien-3β,5α,8α-triol, 5α,6α-epoxy-(22E,24R)-ergosta-8,22-diene-3β,7α-diol, 5α,6α-epoxy-(22E,24R)- ergosta-8(14),22-diene-3β,7α-diol, 5α,6α-epoxy-(22E,24R)-ergosta-8(14),22-diene-3β, 7β-diol, and 22E-7α-methoxy-5α,6α-epoxyergosta-8(14),22-dien-3β-ol showed inhibitory effects on NO production with IC 50 values ranging from 3.24 ± 0.02 to 35.19 ± 0.41 μM compared with L-NMMA (IC 50 49.86 ± 2.13 μM), indicating that they have potential anti-inflammatory activity., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Screening assays showed that total glycoside-rich fraction (TG) of rhizomes of Polygonatum sibiricum unveiled remarkable anti-proliferative activities against three cancer cell lines (A549, HepG2, and Caco2). Activity-guided isolation of TG afforded seven undescribed steroidal glycosides (polygonosides 1-7), along with 24 known glycosides. Their structures were established by 1D and 2D NMR spectroscopic analyses, high-resolution mass spectrometry, and chemical evidence. The isolated steroidal glycosides were tested for their antiproliferative activities against A549, HepG2, and Caco2 cells. Compounds 8, 10, 11, and 16 possessed stronger anticancer activities against A549 cells than the positive control Bay (25.8 μM), with IC 50 values ranging from 5.8 to 24.2 μM. Compound 10 reduced the expression of Blc-2 and pro-caspase3 and increased the production of Bax as determined by western blotting. Molecular docking experiment suggested that 10 bound stably to the BH3-binding groove of the Bcl-2 protein by hydrogen bond interactions. These compounds could be candidates for anticancer agents with cytotoxic activity., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Veramyosides A-J, eleven undescribed stigmastane-type steroids, including one aglycone and ten glycosides, along with three known homologues were isolated from the twigs of Vernonia amygdalina Delile (compositae). All compounds featured a stigmastane-type steroid skeleton with a unique conjugated Δ 7,9(11) diene segment and highly oxygenated side chains with a γ-lactone or an α, β-unsaturated five-membered lactone ring. The structures of veramyosides A-J and their absolute configurations were unambiguously elucidated by HR-ESI-MS, extensive NMR spectroscopy, in situ dimolybdenum CD methods, modified Mosher's method, quantum chemical calculation of their ECD curves, and CD comparison methods on basis of their biogenetic pathway. In addition, all isolates were investigated for their effects on RXRα transcription, and their effects on the NF-κB signaling pathway were also evaluated., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Seven previously undescribed steroidal glycosides, along with three known congeners were isolated from the unripe berries of Solanum nigrum L. (Solanaceae). Their structures were elucidated on basis of 1D and 2D NMR, HR-ESI-MS spectroscopic data and GC analysis after acid hydrolysis. The potential inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide in RAW 264.7 cell line and the anti-proliferative activities against five cancer cell lines (HL-60, U-937, Jurkat, K562 and HepG2) were evaluated. Seven compounds exhibited inhibition activities on NO production with IC 50 values ranging from 11.33 to 49.35 μM. Structure-activity relationships of the isolated compounds were also discussed., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The investigation of the fruits of Solanum nigrum led to the isolation of four previously undescribed steroidal alkaloids, named solanine A, 7α-OH khasianine, 7α-OH solamargine and 7α-OH solasonine, together with six known ones. The structures of the isolated compounds were elucidated unambiguously by spectroscopic data analyses and chemical methods. Solanine A represents an unusual steroidal alkaloid with an unprecedented 6/5/6/5/5/6 hexacyclic ring system, and its structure was confirmed by X-ray single crystal diffraction analysis. Compounds 2-4 were rare naturally occurring steroidal alkaloid glycosides bearing a hydroxyl group at C-7 position. Solanine A showed the most potent inhibitory activity against the LPS-induced NO production in murine RAW264.7 macrophages with an IC 50 value of 3.85 ± 0.71 μM and significant cytotoxicity against MGC803, HepG2 and SW480 cancer cell lines with IC 50 values of 6.00 ± 0.52 μM, 9.25 ± 0.49 μM and 6.23 ± 0.26 μM, respectively., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Ten stigmastane-type steroids bearing unusual Δ 28 -24-hydroxy side chains, dictyopterisins A-J, including three pairs of C-24 epimers, dictyopterisins B/C, F/G, and I/J, were isolated from the brown alga Dictyopteris undulata Holmes, together with two previously reported analogues, (24S)- and (24R)-saringosterol. Their structures were elucidated on the basis of extensive spectroscopic analysis, with their absolute configurations at the stereogenic center C-24 of the side chain being assigned by a direct comparison of 1 H NMR data with those of related known compounds. The absolute configurations of the steroidal nuclei of dictyopterisins A, B, and H were determined using the modified Mosher's method. The mixture of dictyopterisins D and E and dictyopterisin I exhibited promising PTP1B inhibitory activities with IC 50 values of 1.88 and 3.47 μM, respectively, comparable to the positive control oleanolic acid (IC 50 , 2.78 μM). In addition, the mixture of dictyopterisins D and E and dictyopterisins F-J displayed significant cytotoxicities against the human cancer cell lines HL-60 (IC 50 from 1.02 to 2.70 μM) and A-549 (IC 50 from 1.35 to 2.85 μM)., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Five new xanthones, named coxanthones A-E (1-5), together with 21 known secondary metabolites (6-26) that include seven xanthones, five flavonoids, two steroids and seven triterpenoids were isolated from the chemically unexplored whole plant Codonopsis ovata. The structures of new metabolites were elucidated by HRMS, interpretation of NMR spectra and other spectroscopic techniques. The absolute configuration of the stereogenic centre of coxanthone B (2) was determined by electronic circular dichroism (ECD) spectroscopy. This is the first report of xanthones from the genus Codonopsis. All isolated metabolites were evaluated for cytotoxic activity by SRB assay against six human cancer cell lines A549 (lung), PC-3 (prostate), HCT-116 (colon), MCF-7 (breast), SF-295 (CNS), and MDAMB-435 (melanoma). Among the new compounds, coxanthone B (2) exhibited significant inhibitory activity against SF-295 and MDAMB-435 with IC 50 values of 7.0 and 15.0 μM, respectively. Coxanthone A (1) displayed cytotoxicity against A549 cell line at IC 50 value of 22.5 μM. Cytotoxic activity of 1-hydroxy-3,5-dimethoxyxanthone (7), swertiperenine (9) and 1,7,8-trihydroxy-3-methoxyxanthone (10) are reported here first time that exhibited the IC 50 values of 3.0, 5.0 and 21.0 μM against A549, MDAMB-435, and A549 cell lines, respectively. Kaempferol (13) showed most potent cytotoxic activity with an IC 50 values in the 1.0-2.3 μM range against all tested cancer cell lines., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Phytochemical investigation of the stems and leaves of Paris polyphylla var. yunnanensis led to isolation of 12 steroidal saponins, chonglouosides SL-9-SL-20, which had not been described previously, along with 13 known compounds. Their structures were established on the basis of extensive spectroscopic analysis and chemical methods. Four of the twelve steroidal saponins possessed three steroidal aglycones which have not been reported in nature. Steroidal saponins were also evaluated for their cytotoxicities against two human cancer cell lines (HepG2 and HEK293) and anti-HCV effects. One known steroidal saponin was the most cytotoxic compound overall with IC50 values of 2.9 ± 0.5 μM and 5.0 ± 0.6 μM against HepG2 and HEK293 cell lines, respectively, while none showed anti-HCV activity at a concentration of 20 μM., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

A set of 71 triterpenoid and steroid compounds from Ganoderma were periodically classified using a procedure based on information entropy with artificial intelligence. Six features were used in hierarchical order to classify the triterpenoids and steroids structurally. The phytochemicals belonging to the same group in the periodic table present similar antioxidant activity, and those compounds belonging to the same period exhibit maximum resemblance. The periodic classification is related to the experimental bioactivity and antioxidant potency data that are available in the literature: a steroid with a three-ketone group conjugated with two carbon-carbon double bonds in the right side of the periodic table exhibits the greatest antioxidant activity., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Six steroidal glycosides and 14 known compounds were isolated from the underground parts of Yucca glauca (Agavaceae). Their structures were determined from extensive spectroscopic analysis, including analysis of two-dimensional NMR data, and from chemical transformations. The compounds were also evaluated for cytotoxic activities against HL-60 human leukemia cells and A549 human lung adenocarcinoma cells. Four spirostanol glycosides and three furostanol glycosides exhibited cytotoxic activities against both HL-60 and A549 cells. Two of the compounds induced apoptosis in HL-60 cells., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Examination of the bulbs of Bessera elegans (Liliaceae) led to isolation of nine new and five known steroidal glycosides. The structures of the nine compounds were determined based on the results of spectroscopic analysis, including two-dimensional NMR, and hydrolysis followed by chromatographic and spectroscopic analysis. The isolated compounds and derivatives were evaluated for cytotoxicity against HL-60 human promyelocytic leukemia cells, A549 human lung adenocarcinoma cells, and TIG-3 normal human diploid fibroblasts. One compound, the pseudo-furostanol glycoside, induced apoptosis in HL-60 and A549 cells in a time-dependent manner and cell-cycle arrest at the G0/G1 phase in A549 cells., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A pregnane glycoside fraction from the roots of Asclepias tuberosa L. caused normal human skin fibroblasts to proliferate. This fraction contained 21 pregnane glycosides whose structures were established using NMR spectroscopic analysis and chemical evidence. The aglycones of most of these compounds were identified as 8,12;8,20-diepoxy-8,14-secopregnanes, such as tuberogenin or 5,6-didehydrotuberogenin, the same aglycones as constituents of the aerial parts of this plant. Some of these compounds also caused proliferation of skin fibroblasts., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The occurrence of steroidal saponins in the rhizomes of Yucca gloriosa has been detected by LC-MS. On the basis of the LC-MS analysis, five steroidal glycosides, including three spirostane, one furostane and one cholestane glycosides, along with seven known compounds have been isolated and characterized by ESI-MS and by the extensive use of 1D- and 2D-NMR experiments. Quantitative analysis of the steroidal glycosides in Y. gloriosa rhizomes was performed by an LC-MS method validated according to European Medicines Agency (EMEA) guidelines. The dried BuOH extract obtained from rhizomes contains more than 25% w/w of glycosides, thus Y. gloriosa rhizomes can be considered a rich source of steroidal glycosides., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Phytochemical investigation of the whole plants of Agave utahensis Engelm. (Agavaceae) has resulted in the isolation of 15 steroidal saponins (1-15), including five spirostanol saponins (1-5) and three furostanol saponins (11-13). Structures of compounds 1-5 and 11-13 were determined by spectroscopic analysis and the results of hydrolytic cleavage. The isolated compounds were evaluated for their cytotoxic activity against HL-60 human promyelocytic leukemia cells.

Four polyhydroxylated and polyunsaturated furostanol glycosides (1-4), named caucasicosides A (1), B (2), C (3) and D (4), were isolated from the MeOH extract of the underground parts of Helleborus caucasicus, along with four spirostanol derivatives, a furostanol glycoside, a furospirostanol glycoside, 20-hydroxyecdysone and the bufadienolides hellebrigenin and deglucohellebrin. The structures of 1-4 were elucidated as furosta-5,20(22),25(27)-triene-1beta,3beta,11alpha,26-tetrol 26-O-beta-D-glucopyranoside (1), 26-O-beta-D-glucopyranosylfurosta-5,20(22),25(27)-triene-1beta,3beta,11alpha,26-tetrol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (2), 26-O-beta-d-glucopyranosyl-22alpha-methoxyfurosta-5,25(27)-diene-1beta,3beta,11alpha,26-tetrol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (3), 26-O-beta-D-glucopyranosylfurosta-5,20(22),25(27)-triene-1beta,3beta,26-triol 3-O-beta-D-xylopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-4-O-sulfo-alpha-L-arabinopyranoside (4). Structure elucidation was accomplished through the extensive use of 1D- and 2D NMR experiments including 1H-1H (COSY, 1D-TOCSY) and 1H-13C (HSQC, HMBC) spectroscopy along with ESI-MS and HR-ESI-MS. The aglycones of 1-4 have never been reported before.

Five steroidal saponins, shatavarins VI-X, together with five known saponins, shatavarin I (or asparoside B), shatavarin IV (or asparinin B), shatavarin V, immunoside and schidigerasaponin D5 (or asparanin A), have been isolated from the roots of Asparagus racemosus by RP-HPLC and characterized by spectroscopic (1D and 2D NMR experiments) and spectrometric (LCMS) methods.

Seven steroidal glycosides, along with one known glycoside, were isolated from the rhizomes of Ruscus hypophyllum (Liliaceae). Comprehensive spectroscopic analysis, including 2D NMR spectroscopy, and the results of acid hydrolysis allowed the chemical structures of the compounds to be assigned as (23S,25R)-23-hydroxyspirost-5-en-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranoside (1), 1beta-hydroxyspirosta-5,25(27)-dien-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranoside (2), (22S)-16beta,22-dihydroxycholest-5-en-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranoside (3), (22S)-16beta-[(beta-d-glucopyranosyl)oxy]-22-hydroxycholest-5-en-3beta-yl O-alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranoside (4), (22S)-16beta-[(beta-d-glucopyranosyl)oxy]-22-hydroxycholest-5-en-3beta-yl beta-d-glucopyranoside (5), (22S)-16beta-[(beta-d-glucopyranosyl)oxy]-3beta,22-dihydroxycholest-5-en-1beta-yl O-alpha-l-rhamnopyranosyl-(1-->2)-(3,4-di-O-acetyl-beta-d-xylopyranoside) (6), and (22S)-16beta-[(beta-d-glucopyranosyl)oxy]-3beta,22-dihydroxycholest-5-en-1beta-yl O-alpha-l-rhamnopyranosyl-(1-->2)-O-[beta-d-xylopyranosyl-(1-->3)]-beta-d-xylopyranoside (7), respectively. This is the first isolation of a series of cholestane glycosides from a Ruscus species.

Ten steroidal saponins with cis-fused A/B ring, including a smilagenin glycoside, elephanoside A (4), and the five furostanol bisdesmosides, elephanosides B-F (6-10), were isolated from the stems of Yucca elephantipes Regel. (Agavaceae). Their structures were determined by detailed chemical and spectroscopic analysis. All the isolated compounds were tested for their in vitro antifungal and antibacterial activities. Only the two known spirostanol glycosides Ys-II (1) and Ys-IV (2) showed moderate inhibitory activity against the growth of Candida albicans and Cryptococcus neoformans.

Steroidal saponins, 1, 2, 3 and 4, were isolated from the BuOH extract of Smilax china L., along with 13 known compounds, 5-17. Their structures were elucidated on the basis of MS, 1D and 2D NMR spectroscopic analyses and chemical evidence. In the bioassay tests, all compounds showed inhibitory effects on cyclooxygenase-2 enzyme (COX-2) activities at final concentration of 10(-5) M, and only compound 5 showed an inhibitory effect on production of TNFalpha (tumor necrosis factor alpha) in murine peritoneal macrophages at the same concentration.

Three steroidal saponins, racemosides A (1), B (2) and C (3), were isolated from the methanolic extract of the fruits of Asparagus racemosus, and characterized as (25S)-5beta-spirostan-3beta-ol-3-O-{beta-D- glucopyranosyl (1-->6)-[alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->4)]-beta-D-glucopyranoside}, (25S)-5beta-spirostan-3beta-ol-3-O-alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside and (25S)-5beta-spirostan-3beta-ol-3-O-{alpha-L-rhamnopyranosyl-(1-->6)-[alpha-L-rhamnopyranosyl (1-->4)]-beta-D-glucopyranoside}, respectively, by spectrometric analysis and some chemical strategies.

Six steroidal glycosides (1-6) were isolated from the aerial parts of Tribulus alatus Del. (Zygophyllaceae), together with one known cholestane, one spirostane, and six flavonol glycosides. Among them, 1 and 2 possess a furostane-type aglycone, 3 and 6 a cholestane structure, and 4 and 5 a spirostane skeleton. Their structural elucidation was accomplished by extensive spectroscopic methods including 1D ((1)H, (13)C, (13)C DEPT, TOCSY, ROESY) and 2D NMR experiments (DQF-COSY, HSQC, HMBC) as well as ESI-MS analysis.

Four (1, 8-10) and six known (2-7) withanolides were isolated from the leaves of Withania somnifera. Among the new compounds, 10 possessed the rare 3-O-sulfate group with the saturation in A ring and 9 contained unusual 1,4-dien-3-one group. Compound 8 did not have usual 2,3 unsaturation in A ring while 1 had the rare C-16 double bond. The structures of all the compounds were elucidated by spectroscopic methods and chemical transformation.

Four steroidal glycosides, named abutilosides L, M and N, these being 22S,25S-epoxy-furost-5-ene type glycosides, and abutiloside O, a 20-22 seco-type steroidal glycoside, were isolated from the fresh fruits of Solanum abutiloides. Their structures were determined by 2D NMR spectroscopic analysis and chemical evidence.

Two members of a new class of C-nor-D-homo steroidal alkaloids, impranine (1). and dihydroimpranine (2). along with a new pyridyl-pregnane-type steroidal alkaloid, fetisinine (3). and a known base, korsevine (4). were isolated from the bulbs of Fritillaria imperialis. The structures of the compounds were established on the basis of spectroscopic techniques and some chemical transformations. Compounds 1 and 2 form a new class of steroidal alkaloids, named as "impranane."

Two blazeispirane derivatives including blazeispirols G and I were isolated from the cultured mycelia of the fungus Agaricus blazei Murill and were established to be (20S, 22S, 23R, 24S)-14 beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9-triene-11 alpha,23-diol and (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraene-23,28-diol by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A. Furthermore, four blazeispirol derivatives blazeispirols, U, V, V(1) and Z(1) were isolated form the same source described above. Their structures were determined to be (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-23-hydroxyergosta-4,6,8,11-tetraen-3-one, (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-6 alpha,7 alpha,23-trihydroxyergosta-4,8,11-trien-3-one, (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-6 beta,7 alpha,23-trihydroxyergosta-4,8,11-trien-3-one and (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-23-hydroxy-4,5-seco-ergosta-6,8-diene-3,5-dione by extensive 1 D and 2D NMR spectral data.

From the fruits of Trichosanthes tricuspidata, 14 cucurbitane glycosides (khekadaengosides A-J, M-N, cucurbitacin J 2-O-beta-glucopyranoside and cucurbitacin K 2-O-beta-glucopyranoside), a hexanorcucurbitane glucoside (khekadaengoside K) and octanorcucurbitane (khekadaengoside L) were isolated along with two known cucurbitane glucosides (cucurbitacin 2-O-beta-glucopyranoside and 25-O-acetyl-cucurbitacin 2-O-beta-glucopyranoside). Structural elucidations were based on chemical and spectroscopic analyses.

Concomitant extraction and hydrolysis of Solanum steroidal glycoalkaloids in a two-phase system containing an aqueous mineral acid and an organic water immiscible solvent, and having a boiling point under 100(o)C, is described. It is essentially a "one-pot" process, combining direct acid hydrolysis of the glycosides in the plant material and in situ extraction of the released aglycones after alkali treatment, in a single step, the various ingredients being added simultaneously or sequentially, as required. Application of the process to fruits, leaves, and tissue cultures of Solanum khasianum Clarke plants, either fresh or in dried, finely ground form, using a two-phase aqueous hydrochloric acid-toluene system, proved to be very suitable for continuous production of pure solasodine which is a valuable raw steroid for the preparation of steroidal drugs. Pure Solanum glycoalkaloids were also prepared and hydrolysed accordingly. The process has analytical applications too, and could be extended in a general way to glycosides in other series for preparation of their related aglycones.

A steroidal saponin, named tuberoside, together with seven known compounds, were isolated from the seeds of Allium tuberosum Rottl. ex Spreng. Its structure was established by spectroscopic data, hydrolysis, and comparison with spectral data of known compounds to be (2alpha, 3beta, 5alpha, 25S)-2,3,27-trihydroxyspirostane 3-O-alpha-L-rhamnopyranoyl-(1-->2)-O-[alpha-L-rhamnopyranoyl-(1-->4)]-beta-D-glucopyranoside.

An approach, using well characterized procedures, is presented that should be of general applicability for the structural elucidation of complex sugar moieties of natural products. The methods used are exemplified by the structure elucidation of a new gitogenin-based steroidal saponin that has a strong leishmanicidal activity similar to preparations used in clinical practice and has been isolated by bioactivity-guided fractionation of the ethanolic extract of Yucca filamentosa L. leaves. The saponin has been characterized as 3-O-((beta-D-glucopyranosyl-(1-->3)- beta-D-glucopyranosy-(1-->2))(alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->3))-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranosyl)-25R,5alpha-spirostan-2alpha,3beta-diol.

Three bufadienolides, hellebortin A (5-[beta-D-glucopyranosyloxy]-10,14,16-trihydroxy-19-nor-[5beta,10beta,14beta,16beta]-bufa-3,20,22-trienolide [1]), hellebortin B (5-[beta-D-glucopyranosyloxy]-3,4-epoxy-14-hydroxy-19-oxo-bufa-20,22-dienolide [2]) and hellebortin C (5-[beta-D-glucopyranosyloxy]-3,4-epoxy-10,14-dihydroxy-19-nor-bufa-20,22-dienolide [3]), together with 20-hydroxyecdysone 3-O-beta-D-glucoside (4) and 20-hydroxyecdysone (5) have been isolated by bioassay- and RIA-directed HPLC analyses of a methanol extract of the seeds of Helleborus torquatus. The structure and relative stereochemistry of the novel bufadienolide hellebortin A (1) and the structures of hellebortin B (2) and hellebortin C (3) were determined unambiguously by comprehensive analyses of their 1D and 2D NMR data. These five compounds are isolated from Hellborus torquatus for the first time. The biological activities of compound 1, 4 and 5 as ecdysteroid agonists and antagonists have been assessed.

To gain a better understanding of brassinosteroid biosynthesis, the levels of brassinosteroids and sterols related to brassinolide biosynthesis in Arabidopsis, pea, and tomato plants were quantified by gas chromatography-selected ion monitoring. In these plants, the late C-6 oxidation pathway was found to be the predominant pathway in the synthesis of castasterone. Furthermore, all these plant species had similar BR profiles, suggesting the presence of common biosynthetic control mechanisms. The especially high levels of 6-deoxocathasterone and 6-deoxocastasterone may indicate that their respective conversions to 6-deoxoteasterone and castasterone are regulated in planta and hence are important rate-limiting steps in brassinosteroid biosynthesis. Other possible rate-limiting reactions, including the conversion of campestanol to 6-deoxocathasteonre. are also discussed. Tomato differs from Arabidopsis and pea in that tomato contains 28-norcastasterone as a biologically active brassinosteroid, and that its putative precursors, cholesterol and its relatives are the major sterols.

Anti-inflammatory activity guided fractionation of the n-hexane soluble fraction of a 70% aqueous methanolic extract of the dried fruits of Forsythia suspensa afforded two new triterpenes. The structures of these compounds were elucidated as 3beta-acetyl-20,25-epoxydammarane-24alpha-ol (1) and 3beta-acetyl-20,25-epoxydammarane-24beta-ol (2) on the basis of spectral data interpretation as well as by comparison with those of structurally similar compounds.

Highly oxygenated ecdysteroids, (24R)-11 alpha, 20,24-trihydroxyecdysone and 11 alpha,20,26-trihydroxyecdysone, have been isolated from the polar fraction of Vitex canescens root bark. The latter exists as two C-25 epimers which could be separated by reversed-phase HPLC.

Two novel diglycosylated steroidal alkaloids of 5 delta-pregnene nucleus, named obtusine-20(R)-O-[beta-thevetopyranosyl-(1-->4)-beta-cyma ropyranoside] and obtusolactam-20(R)-O-[beta-thevetopyranosyl-(1-->4)-beta- cymaropyranoside], together with the known beta-sitosteryl-3-O-beta-glucopyranoside were isolated from the roots of Cryptolepis obtusa N. E. Br.

The structures of two new constituents, a beta-glycoside (1) and a steroid (2), isolated from the twigs and thorns of Castela polyandra, were established by a combination of spectroscopic and single-crystal X-ray analysis.

From the seeds and siliques of Arabidopsis thaliana, six brassinosteroids, brassinolide, castasterone, typhasterol, 6-deoxocastasterone, 6-deoxotyphasterol and 6-deoxoteasterone, were identified by GC-mass spectrometry or GC-selected ion monitoring. As the occurrence of castasterone, typhasterol, 6-deoxocastasterone and 6-deoxotyphasterol in the shoots of A. thaliana has already been reported, this study provides evidence for the occurrence of the above four brassinosteroids in different organs, seeds and siliques, and the first evidence for the occurrence of brassinolide and 6-deoxoteasterone in A. thaliana. All brassinosteroids identified in this study belong to important components of both the early and late C-6 oxidation pathways, which were established in the cultured cells of Catharanthus roseus. This suggests that both pathways are operating in A. thaliana to produce the most biologically active brassinosteroid, brassinolide, which is responsible for growth and development of the plant.

Phytochemical examination of the underground parts of Ruscus aculeatus has been undertaken as part of systematic study of plants of the Liliaceae. Six new spirostanol saponins and five new furostanol saponins were isolated, and their structures were assigned on the basis of spectroscopic analysis, including two-dimensional NMR techniques, and hydrolysis. Ruscogenin diglycoside with three acetyl groups attached to the inner galactosyl moiety and its corresponding 26-glucosyloxyfurostanol saponin showed cytostatic activity on leukemia HL-60 cells.

In addition to khasianine, solamargine, xylosylsolamargine and solasonine, three steroidal alkaloid glycosides, solasuaveoline, dihydrosolasuaveoline and isosolasuaveoline, have been isolated from aerial parts of Solanum suaveolens. The structures have been assigned by NMR investigations as (25R)-3 beta-{O-beta-D-glucopyranosyl-(1-->2)-O-beta-D- glucopyranosyl-(1-->4)-[O-alpha-L-rhamnopyranosyl-(1-->2)]-beta-D- galactopyranosyloxy}-22 alpha N-spirosol-5-ene, (25R)-3 beta-{O-beta-D-glucopyranosyl-(1-->2)-O- beta-D-glucopyranosyl-(1-->4)-[O-alpha-L-rhamnopyranosyl-(1-->2)]-beta-D - galactopyranosyloxy}-5 alpha, 22 alpha N-spirosolane and (25R)-3 beta-{O-beta-D-glucopyranosyl-(1-->6)-O- beta-D-glucopyranosyl-(1-->3)-[O-alpha-L-rhamnopyranosyl-(1-->2)]-beta-D - galactopyranosyloxy}-22 alpha N-spirosol-5-ene, respectively.

From the whole plant of Caraluma umbellata, three new C-21 steroidal glycosides, named as carumbellosides III-V, were isolated and their structures elucidated by extensive spectroscopic experiments, devoid of any derivatisation, as caralumagenin 3-O-beta-D-glucopyranosyl(1-->4)-beta-D-digitalopyranoside-20-O-be ta- D-glucopyranoside, caralumagenin 3-O-beta-D-glucopyranosy(1-->4)- beta-D-digitalopyranoside-20-O-(2-O- benzoyl)-beta-D-glucopyranoside and caralumagenin 3-O-[6-O-benzoyl-beta-D-glucopyranosyl(1-->4)]-beta-D- digitalopyranoside-20-O-(2-O-benzoyl)-beta-D-glucopyranoside. The determination of the absolute configuration of the aglycone as (20 R), the conformations of the sugars and the unambiguous assignments of their NMR spectroscopic signals were achieved by a combination of 2D-NMR techniques. The isolates were devoid of significant cytotoxity in the UIC human cancer cell panel.

A new phytoecdysteroid, 24(24(1))[Z]-dehydroamarasterone B, has been isolated from seeds of Leuzea (Rhaponticum) carthamoides. It has been unambiguously identified by CIMS, 13C NMR and 1H NMR spectroscopy. The biological activity of the ecdysteroid has been determined in the Drosophila melanogaster BII bioassay. The ED50 (5.2 x 10(-7) M) is 70-fold higher than that for 20-hydroxyecdysone (7.5 x 10(-9) M).

A new steroidal compound 1-oxo-7 alpha-hydroxysitosterol was isolated from the whole plant of Salvia glutinosa in addition to 11 known triterpenoids and three steroids. The structures were established by spectral data. Cytotoxic activity of the new compound and 7 alpha-hydroxysitosterol were tested against P-388 and KB systems; only marginal activity was found.

Four dammarane-type saponins were isolated by means of centrifugal partition chromatography from the root bark of Zizyphus lotus. Their structures were elucidated using a combination of 1D and 2D 1H and 13C NMR spectra and mass spectroscopy. One of these glycosides is the known jujuboside A. The others are three new dammarane saponins, identified as 3-O-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl (1-->3)-[alpha-L-rhamnopyranosyl(1-->2)]-alpha-L-arabinopyranosyl jujubogenin = jujuboside C, 3-O-alpha-L-rhamnopyranosyl (1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-galactopyranosyl lotogenin = lotoside I, and 3-O-alpha-L-rhamnopyranosyl(1-->2)-[beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranosyl lotogenin = lotoside II. Lotogenin is a new dammarane derivative identified as (15R, 16R, 20R, 22R)-16 beta, 22-epoxydammar-24-ene-3 beta, 15 alpha, 16 alpha, 20 beta-tetraol.

A new C22-steroid glycoside was isolated from the underground parts of Hosta plantaginea var. japonica, together with a known furostanol saponin and three known spirostanol saponins. The structure of the new steroid glycoside was characterized by spectroscopic analysis and acid-catalysed hydrolysis as 2 alpha, 3 beta, 16 beta-trihydroxy-5 alpha-pregn-20(21)-ene-carboxylic acid gamma-lactone 3-O-¿O-beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1--> 4)-beta-D-galactopyranoside¿. The isolated compounds were assayed for their cytostatic activity on leukaemia HL-60 cells. The spirostanol saponins showed cytostatic activity in a dose-dependent manner with the IC50 values ranging between 1 and 3 micrograms ml-1.

Three new steroidal saponins were isolated from the rhizomes of Smilax officinalis. The structures of these saponins were established by extensive spectral data, hydrolysis and chemical correlation as sarsasapogenin 3-O-beta-D-glucopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->6 )-beta- D-glucopyranoside, neotigogenin 3-O-beta-D-glucopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->6 )]-beta- D-glucopyranoside and 25S-spirostan-6 beta-ol 3-O-beta-D-glucopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->6 )]-beta- D-glucopyranoside. Acid hydrolysis of the latter compound gave a sapogenin which has a new orientation of an hydroxyl on the steroidal skeleton. A route is proposed for the biogenesis of the latter sapogenin which is an uncommon steroidal aglycone.

Seven steroidal saponins were isolated from the stems of Nolina recurvata, five of which appeared to be new compounds and were assigned as spirosta-5,25(27)-diene-1 beta,3 beta-diol (neoruscogenin) 1-O--O-alpha-L-rhamnopyranosyl-(1--> 2)-O-[beta-D-xylopyranosyl-(1-->3)]-alpha-L-arabinopyranoside-, (25S)-spirost-5-ene-1 beta,3 beta-diol [(25S)-ruscogenin] 1-O-{O-alpha-L-rhamnopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1--> 3)]-alpha-L-arabinopyranoside}, neoruscogenin 1-O-{O-alpha-L-rhamnopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1--> 3)]-beta-D-fucopyranoside}, 26-O-beta-D-glucopyranosyl-22-O-methylfurosta-5,25(27)-diene-1 beta,3 beta,22 xi,26-tetrol 1-O--O-alpha-L-rhamnopyranosyl-(1--> 2)-O-[beta-D-xylopyranosyl-(1-->3)]-alpha-L-arabinopyranoside- and 26-O-beta-D-glucopyranosylfurosta-5,20(22),25(27)-triene-1 beta,3 beta,26-triol 1-O-{O-alpha-L-rhamnopyranosyl-(1--> 2)-alpha-L-arabinopyranoside}. The isolated saponins were evaluated for their inhibitory activity on cyclic AMP phosphodiesterase to identify new compounds with medicinal potential.

In addition to hecogenin 3-O-beta-D-glucopyranosyl(1--> 4)-beta-D-galactopyranoside, two new steroidal saponins were isolated from the aerial parts of Tribulus terrestris L. On the basis of chemical and spectroscopic evidence, especially 2D NMR spectroscopic techniques, the structures of the new saponins were established as 26-O-beta-D-glucopyranosyl-3-O-[-beta-D-xylopyranosyl(1--> 3)--beta-D-galactopyranosyl(1-->2)--beta-D-glucopyranosyl (1--> 4)-beta-D-glucopyranosyl]-5 alpha-furost-20(22)-en-12-one-3 beta,26-diol and 26-O-beta-D-glucopyranosyl-3-O-[{beta-D-xylopyranosyl (1-->3)--beta-D-galactopyranosyl(1-->2)--beta-D-glucopyranosyl(1 -->4)-beta-D-glucopyranosyl]-5 alpha-furostan-12-one-3 beta,22,26-triol.

Three new spirostanol saponins and two new furostanol saponins were isolated from the underground parts of Hosta longipes. Their structures were determined to be (25R)-5 alpha-spirostane-2 alpha, 3 beta-diol (gitogenin) 3-O-{O-alpha-L -rhamnopyranosyl-(1-->2)-beta-D-galactopyranoside}, gitogenin 3-O-{O-alpha-L-rhamnopyranosyl-(1-->2) -O-[beta-D-glucopyranosyl-(1-->4)]-beta-D-galactopyranoside-, (25R)-5 alpha-spirostan-3 beta-ol (tigogenin) 3-O-{O-alpha-L-rhamnopyranosyl-(1-->2) -O-[beta-D-glucopyranosyl-(1-->4)]-beta-D-galactopyranoside-, 26-O-beta-D-glucopyranosyl-22-O-methyl-(25R)-5 alpha-furostane-2 alpha,3 beta, 22 xi,26-tetrol 3-O-{O-alpha-L-rhamnopyranosyl -(1-->2)-beta-D-galactopyranoside} and 26-O-beta -D-glucopyranosyl-22-O-methyl-(25R)-5 alpha-furostane-2 alpha,3 beta,22 xi,26-tetrol 3-O-{O-alpha-L -rhamnopyranosyl-(1-->2)-O-[beta-D-glucopyranosyl -(1-->4)]-beta-D-galactopyranoside}, respectively. The isolated saponins and their derivatives were examined for inhibitory activity on 12-O-tetradecanoylphorbor-13-acetate-stimulated 32P-incorporation into phospholipids of HeLa cells as the primary screening test to find new antitumour-promoter compounds.

In addition to solamargine, isoanguivine and solasonine, two new steroid alkaloid glycosides, xylosylsolamargine and xylosyl-beta-solamarine, have been isolated from the aerial parts of Solanum coccineum, the structures of which have been elucidated as (25R)-3 beta-[O-beta-D-xylopyranosyl-(1-->2)-O-alpha-L-rhamnopyranosyl- (1-->4)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranosyloxy+ ++]-22 alpha N-spirosol-5-ene and (25S)-3 beta-[O-beta-D-xylopyranosyl-(1-->2)-O-alpha-L-rhamnopyranosyl- (1-->4)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranosyloxy+ ++]-22 beta N-spirosol-5-ene.

Phytochemical examination of the dichloromethane extract of the European fungus Fomitopsis pinicola led to the isolation of a new lanostanoid derivative identified from spectral and chemical evidences as 3 alpha-(4-carboxymethyl-3-hydroxy-3-methylbutanoyloxy)-lanosta++ +-8,24-dien-21-oic acid. In addition, seven known triterpenes, polyporenic acid C, 3 alpha-acetyloxylanosta-8,24-dien-21-oic acid, ergosta-7,22-dien-3 beta-ol,21-hydroxylanosta-8,24-dien-3-one, pinicolic acid A, trametenolic acid B and pachymic acid, were also isolated. Antimicrobial activity against Bacillus subtilis in a TLC bioassay was observed for five of the isolated steroids.