Steroidal saponins from Smilacina japonica

Three new steroidal saponins, japonicoside A (1), japonicoside B (2) and japonicoside C (3) were isolated from the dried rhizomes and roots of Smilacina japonica A. Gray. Their structures were elucidated as (25S)-5α-spirostan-9(11)-en-3β-ol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (1), (25S)-5α-spirostan-9(11)-en-3β,17α-diol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (2) and (25S)-5α-spirostan-9(11)-en-3β,17α,24α-triol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside (3) on the basis of chemical methods and detailed spectroscopic analysis, including 1D, 2D NMR and HR-ESI-MS. The cytotoxicity of isolated compounds was evaluated in vitro for cytotoxic properties against human hepatocellular carcinoma cells (SMMC-7221) and human colorectal adenocarcinoma cells (DLD-1), respectively.     

A new steroidal saponin from the dried stems of Asparagus officinalis L

Yamogenin II (1), a new steroidal saponin with a unique aglycone moiety, and (25S)-spirostan-5-ene-3β-ol-3-O-α-l-rhamnopyranosyl-(1,2)-[α-l-rhamnopyranosyl-(1,4)]-β-d-glucopyranoside (2), were isolated from the dried stems of Asparagus officinalis L. The structure of 1 was assessed by spectroscopial analysis as (25S)-spirostan-5-ene-3β,21-diol-3-O-α-l-rhamnopyranosyl-(1,2)-[α-l-rhamnopyranosyl-(1,4)]-β-d-glucopyranoside.     

New furostanol saponins from Smilax aspera L. and their in vitro cytotoxicity

The occurrence of the two new cis-fused A/B rings furostanol saponins (25S)-26-O-β-d-glucopyranosyl-5β-furostan-1β,3β,22α,26-tetraol-1-O-β-d-glucopyranoside and (25S)-26-O-β-d-glucopyranosyl-5β-furostan-1β,2β,3β,5β,22α,26-hexaol and the known compounds (25S)-26-O-β-d-glucopyranosyl-5β-furostan-3β,22α,26-triol-3-O-α-l-rhamnopyranosyl-(1→2)-O-β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranoside and (25S)-26-O-β-d-glucopyranosyl-5β-furostan-3β,22α,26-triol-3-O-β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranoside, trans-resveratrol, (+) catechin and (−) epicatechin in the rhizomes of Smilax aspera is reported. All saponins have been isolated as their 22-OMe derivatives, which were further subjected to extensive spectroscopic analysis. The isolated furostanol saponins were evaluated for cytotoxic activity against human normal amniotic and human lung carcinoma cell lines using neutral red and MTT assays. In vitro experiments showed significant cytotoxicity in a dose dependent manner with IC₅₀ values in the range of 32.98-94.53 µM.     

(-)-Veranigrine, a new steroidal alkaloid from Veratrum nigrum L

A new steroidal alkaloid, (-)-veranigrine (1) was isolated from the roots and rhizomes of Veratrum nigrum L. By means of spectroscopic methods its structure was established as (20S, 25S)-iminocholesta-5,22(N)-diene-1beta,3beta-diol.     

Two new triterpene saponins from the aerial parts of Paraquilegia microphylla

Two new triterpene saponins, paraquinosides A (1) and B (2) were isolated from the aerial parts of Paraquilegia microphylla (Royle) Dromm. et Hutch, a Tibetan ethnic medicine distributed in the Qinghai–Tibet Plateau. On the basis of 1D and 2D NMR evidence, their structure was elucidated as 3-O-α-L-rhamnopyranosyl (1→2)-β-D-glucopyranosyl-15-dehydroxyl-16-O-methyl-24, 25-deoxy-26-hydroxylshengmanol-26-O-β-D-glucopyranoside (1) and 3-O-α-L-Rhamnopyranosyl (1→2)-[β-D-glucopyranosyl(1→3)]-β-D-glucopyranosyl-15-dehydroxyl-16-O-methyl-24, 25-deoxy-26-hydroxylshengmanol-26-O-β-D- glucopyranoside (2), respectively.     

Solanum incanum and S. heteracanthum as sources of biologically active steroid glycosides: confirmation of their synonymy

A new spirostanol saponin (1), along with four known saponins, dioscin (2), protodioscin (3), methyl-protodioscin (4), and indioside D (5), and one known steroid glycoalkaloid solamargine (6) were isolated from the two synonymous species, Solanum incanum and S. heteracanthum. The structure of the new saponin was established as (23S,25R)-spirost-5-en-3β,23-diol 3-O-{β-D-xylopyranosyl-(1→2)-O-α-L-rhamnopyranosyl-(1→4)-[O-α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside}, by using a combination of 1D and 2D NMR techniques including (1)H, (13)C, COSY, TOCSY, NOESY, HSQC and HMBC experiments and by mass spectrometry. The compounds 1, 3, 4 and 5 were evaluated for cytotoxicity against five cancer cell lines and for antioxidant and cytoprotective activity.     

Isolation of new flavan-3-ol and lignan glucoside from Loropetalum chinense and their antimicrobial activities

Phytochemical and antimicrobial activity study on the ethanol extract of the leaves and stems of Loropetalum chinense led to the isolation of a new flavan-3-ol compounds, 8-[1-(3,4-dihydroxyphenyl)-3-methoxy-3-oxopropyl]-catechin (loropetaliside A) (1) and a new lignan glucoside, 1-(5-hydroxy-3-methoxyphenyl)-2-(2-β-glucopyranosyl-4-hydroxy-5-(1-(E)propen-3-ol)-phenyl)-propane-3-ol (loropetaliside B) (3) and several known compounds manglieside D (2), quercetin (4), kaempferol-3-O-D-glucopyranoside (5), quercetin-3-O-β-L-rhamnoside (6) and tiliroside (7). Their structures were elucidated on the basis of extensive spectroscopic analysis.     

Two new steroidal saponins from Selaginella uncinata (Desv.) Spring and their protective effect against anoxia

Four steroidal saponins were isolated from the anti-anoxic fraction of the 60% EtOH extract of Selaginella uncinata, including two new compounds, (3β, 7β, 12β, 25R)-spirost-5-ene-3, 7, 12-triol-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-[α-L-rhamnopyranosyl-(1 → 4)]-O-β-d-glucopyranoside (1), (2α, 3β, 12β, 25R)-spirost-5-ene-2, 3, 12-triol-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-[α-L-rhamnopyranosyl-(1 → 4)]-O-β-d-glucopyranoside (2) and two known compounds, (3β, 12β, 25R)-spirost-5-ene-3,12-diol-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-[α-L-rhamnopyranosyl-(1 → 4)]-O-β-d-glucopyranoside, (3), (1α, 3β, 25R)-spirost-5-ene-2-diol-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-[α-L-rhamnopyranosyl(1 → 4)]-O-β-d-glucopyranoside (4). The four compounds showed potent protective effect against anoxia in the anoxic PC12 cells assay, among which compounds 1 and 2 were the most active. To our knowledge, this is the first study to report the steroidal saponins in the plant S. uncinata and demonstrate their protective effect against anoxia in PC12 cell assay.     

Sesquiterpenes and acetogenins from the marine red alga Laurencia okamurai

Three new halogenated sesquiterpenes, 10-bromo-7α,8α-expoxychamigr-1-en-3-ol (1), 10-bromo-β-chamigren-8-ol (2), and 10-bromo-3-chlorocupar-5-en-2-ol (3), one new C₁₂-acetogenin, desepilaurallene (7), one new naturally occurring sesquiterpene, 7-hydroxylaurene acetate (4), two known sesquiterpenes, allolaurinterol acetate (5) and laurene (6), and one known C₁₅-acetogenin, epilaurallene (8), were isolated from the marine red alga Laurencia okamurai collected from the coast of Rongcheng, China. The structures of these compounds were unambiguously established by 1D, 2D NMR and mass spectroscopic techniques. The bioassay results showed that 4, 5 exhibited potent antibacterial activity, and 1, 4, 5 were toxic to brine shrimp.     

Glycocerebroside bearing a novel long-chain base from Sagina japonica (Caryophyllaceae)

A new glycocerebroside (1), along with one reported one (2), was isolated from the ethanol extract of Sagina japonica (Caryophyllaceae) and was fully characterized. The structures of two compounds were identified as (2S, 3S, 4R, 8E)-1-(β-D-glucopyranosyl-3, 4-dihydroxy-2-[(R)-2′- hydroxypalmitoyl]amino-8-heptadecaene (1) and (2S, 3R, 8E)-1-(β-D-glucopyranosyl-3-hydroxy-2-[(R)-2′-hydroxypalmitoyl]amino-8-octadecaene (2) by using spectroscopic methods (¹H, ¹³C, and 2D NMR, MS) and chemical degradation.     

Pregnane alkaloids from Sarcococca hookeriana var. digyna

Fourteen pregnane-type steroidal alkaloids were isolated from the ethanolic extracts of whole Sarcococca hookeriana var. digyna plants. Their structures were elucidated on the basis of spectral data. Three of them were identified as new steroidal alkaloids: (S)-20-(N,N-dimethylamino)-16α,17α-epoxy-3β-methoxy-pregn-5-ene (1), (20S)-20-(N,N-dimethylamino)-3β-tigloylamino-5α-pregn-11β-ol (2), and (20S)-2α,4β-bis(acetoxy)-20-(N,N-dimethylamino)-3β-tigloylamino-5α-pregnane (3). Some of the isolated compounds showed estrogen biosynthesis-promoting effects in human ovarian granulosa-like KGN cells. The EC₅₀ values for the most effective compounds, vagnine B (6) and funtumafrine C (12), were 71 μM and 67 μM, respectively.     

Aporphine alkaloids,clerodane diterpenes,and other constituents from Tinospora cordifolia

Phytochemical investigation of the methanol extract of Tinospora cordifolia aerial parts led to the isolation of four new and seven known compounds. The structures of two new aporphine alkaloids, N-formylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside A, 1) and N-acetylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside B, 2), a new clerodane diterpene, tinoscorside C (3), and a new phenylpropanoid, sinapyl 4-O-β-d-apiofuranosyl-(1 → 6)-O-β-d-glucopyranoside (tinoscorside D, 6) were determined by extensive spectroscopic methods including FTICR-MS and 1D and 2D NMR.     

Five new cyotoxic steroidal glycosides from the fruits of Solanum torvum

The fruits of Solanum torvum Swartz, commonly known as Turkey berry, are edible and commonly used as a vegetable in the South Indian population's diet and as an essential ingredient in Thai cuisine. Five new steroidal glycosides together with five known ones were isolated from the fruits of S. torvum Swartz. Based on chemical and spectral evidence, the five new compounds were identified to be 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3β,6α,26-triol-6-O-[α-l-rhamnopyranosyl-(1 → 3)-O-β-d-quinovopyranoside] (1), 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3-one-6α,26-diol-6-O-[α-l-rhamnopyranosyl-(1 → 3)-O-β-d-quinovopyranoside] (2), 25(S)-26-O-β-d-glucopyranosyl-5α-furost-22(20)-en-3β,6α,26-triol-6-O-β-d-quinovopyranoside (3), 5α-pregn-16-en-20-one-3β,6α-diol-6-O-[α-l-rhamnopyranosyl-(1 → 3)-β-d-quinovopyranoside] (4), and 5α-pregn-16-en-3,20-dione-6α-ol-6-O-[α-l-rhamnopyranosyl-(1 → 3)-β-d-quinovopyranoside] (5). These new compounds were assayed for cytotoxicities in vitro, and 1 to 4 showed cyotoxic activity against the human melanoma cell line A375, with IC₅₀ values of 30 μM to 260 μM.     

Cucurbitane-type triterpenoids from the stems and leaves of Momordica charantia

Six new cucurbitane-type triterpenoids, karavilagenin F (1), karavilosides XII and XIII (2, 3), momordicines VI, VII, and VIII (4, 5 and 6), along with four known ones, 5β,19-epoxy-25-methoxycucurbita-6,23-diene-3β,19-diol (7), 5β,19-epoxycucurbita-6, 23-diene-3β,19,25-triol (8), kuguacin R (9), and (19R,23E)-5β,19-epoxy-19-methoxycucurbita-6,23,25-trien-3β-ol (10), were isolated from the stems and leaves of Momordica charantia L. Their chemical structures were elucidated by extensive 1D NMR and 2D NMR (HSQC, HMBC, COSY, and ROESY), MS experiments, and CD spectrum. Compound 6 showed weak cytotoxicity against five human cancer cells lines with IC₅₀ values of 14.3–20.5 μmol/L.     

In vitro effects on intestinal bacterium of physalins from Physalis alkekengi var. Francheti

Intestinal probiotic bacterium stimulative activity-guided fractionation of Physalis alkekengi var. Francheti calyces extract resulted in the isolation of four new physalins (1–4). Their structures were elucidated as 5α, 6β-dihydroxy-25, 27-dihydro-7-deoxyphysalin A (1), 5α, 6β-dihydroxyphysalin R (2), 3β-hydroxy-2-hydrophysalin A (3) and 5α-hydroxy-7-dehydro-25, 27-dihydro-7-deoxyneophysalin A (4) by UV, MS, 1D and 2D NMR spectroscopy. Growth curves of Lactobacillus delbrueckii and Escherichia coli for different total physalins extract (TPE) concentrations were tested in vitro. Middle concentrations (0.78 mg/mL–1.56 mg/mL) of TPE promoted the growth of L. delbrueckii, but all inhibited the growth of E. coli, in which the bacteriostatic activity increased while TPE concentration increases. Physalins showed stimulative effects on the growth of probiotic bacteria but inhibitory effects on the growth of pathogenic bacteria.     

New bisbenzylisoquinoline alkaloid from Laureliopsis philippiana

Phytochemical investigation of Laureliopsis philippiana resulted in isolation of a new bisbenzylisoquinoline alkaloid (1) named laureliopsine A. The structure was established by spectroscopic methods, including 2D homo- and heteronuclear NMR experiments. This finding of a bisbenzylisoquinoline alkaloid in Laureliopsis supports its close relationship to Atherosperma and its taxonomic segregation from Laurelia.     

Kujigamberol, a new dinorlabdane diterpenoid isolated from 85million years old Kuji amber using a biotechnological assay

A new compound, 15,20-dinor-5,7,9-labdatriene-18-ol (1), named kujigamberol, was isolated from amber, fossilized tree resin from the Kuji area in Japan, has been dated as being 85 million years old (late Cretaceous). Kujigamberol was identified using the hypersensitive mutant yeast (zds1? erg3? pdr1? pdr3?) with respect to Ca²⁺-signal transduction. The structure was elucidated on the basis of spectroscopic analysis including 1D NMR, 2D NMR and HR-EI-MS. It was different from known diterpenoids with a similar activity isolated from Baltic amber (agathic acid 15-monomethyl ester (2), dehydroabietic acid (3) and pimaric acid (4)). Kujigamberol showed glycogen synthase kinase-3β (GSK-3β) inhibition activity involving the growth restored activity against the mutant yeast and was cytotoxic to HL60 cells (IC₅₀ = 19.6 μM).     

Dammarane-type glycosides and long chain sesquiterpene glycosides from Gynostemma yixingense

A new dammarane-type glycoside and a new long chain sesquiterpene glycoside, along with nine known compounds 20(S)-ginsenoside Rh1 (3), 20(R)-ginsenoside Rh1 (4), ginsenoside F1 (5), amarantholidoside IV (6), ginsenoside Rc (7), 20(S)-ginsenoside Rg2 (8), 20(R)-ginsenoside Rg2 (9), ginsenoside Rd (10) and gypenoside XLVI (11) were isolated from Gynostemma yixingense. The structures of the new compounds were determined on the basis of spectroscopic analysis, including 1D-, 2D-NMR and ESI-MS techniques as well as by comparison of the spectral data with those of related compounds as 2α,3β,20(S)-trihydroxydammar-24-ene-3-O-[β-d-glucopyranosyl((1 → 2)-β-d-glucopyranosyl]-20-O-[β-d-xylopyranosyl((1 → 6)-β-d-glucopyranoside] (1) (2E,6E)-10-β-d-glucopyranosyl-1,10,11-trihydroxy-3,7,11-trimethyldodeca-2,6-diene (2).     

Three drimane sesquiterpene glucoside from the aerial parts of Dryopteris fragrans (L.) schot

Sesquiterpene glucoside was isolated from the aqueous extract of the aerial parts of Dryopteris fragrans (L.) schot. Three new sesquiterpene glucoside xianglinmaojuesides A–C (1–3), 3β,11-dihydroxy-drim-8 (12)-en-11-O-β-d-glucopyranoside (1), 3β,11-dihydroxy-drim-8(12)-en-3-O-β-d-glucopyranoside (2), and 11,14-dihydroxy-drim-8(12)-en-11-O-β-d-glucopyranoside (3) were finally obtained by reversed-phase HPLC and their structures were elucidated by HRESIMS and 1D, 2D NMR analyses.     

New triterpenoid saponins from Leontice smirnowii

Three new triterpene saponins, leonticins I (1), J (2) and L (3) were isolated from the tubers of Leontice smirnowii. On the basis of spectroscopic methods, including 2D NMR experiments (DEPT, gs-COSY, gs-HMQC, gs-HMBC and gs-HSQC-TOCSY), mass spectrometry (HR-ESI-MS) and chemical degradation, the structures of the new compounds were elucidated as 3-O-β-D-glucopyranosyl-(1 → 3)-[β-D-xylopyranosyl-1 → 2)]-α-L-arabinopyranosyl-28-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]-3β-hydroxy-30-norolean-12,20(29)-dien-28-oic acid (1), 3-O-[β-D-xylopyranosyl-(1 → 3)-β-D-galactopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-arabinopyranosyl]-28-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]-3β-hydroxy-30-norolean-12,20(29)-dien-28-oic acid (2) and 3-O-[β-D-xylopyranosyl-(1 → 3)-β-D-galactopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)]-[β-D-xylopyranosyl-(1 → 2)]-α-L-arabinopyranosyl]-28-O-[α-L-rhamnopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl]-3β-hydroxy-30-norolean-12,20(29)-dien-28-oic acid (3), respectively. The aglycone 3β-hydroxy-30-norolean-12,20(29)-dien-28-oic acid was observed for the first time in Leontice species.