• YAKHAK HOEJI
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• v.42 no.5
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• pp.500-506
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• 1998

Steroidal 2${\beta},\;3{\beta}$--epoxy compound was prepared from asiaticoside via six steps and reduced regioselectively with lithium aluminum hydride. Epoxide ring opening furnished 9 as a sole product at reflux condition through axial hydride attack at C-3.

• YAKHAK HOEJI
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• v.41 no.5
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• pp.547-553
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• 1997

The purpose of this investigation was to determine the inhibition on $Na^+,\;K^+$-ATPase, cyclic AMP phosphodiesterase and platelet activation by marine sterols isolated from octocorals. Three marine polyhydroxysterols, 7${\alpha},\;8{\alpha}-epoxy-3b{\beta},\;5{\alpha},\;6{\alpha}-trihydroxycholestane (1),\;24-methyl-7{\alpha},\;8{\alpha}-epoxy-3{\beta},\;5{\alpha},\;6{\alpha}-trihydroxycholest-22-ene (2),\;and\;7{\alpha},\;8{\alpha}-epoxy-3{\beta},\;5{\alpha},\;6{\alpha}-trihydroxycholest-22-ene (3)$, were isolated from the Gorgonian Acabaria undulata. Five marine sterols(compound 4, 5, 6, 7, 8) were isolated from the soft coral Alcyonium gracillimum. Three marine polyhydroxysterols (1, 2, 3) and pregna-1. 20-diene-3-one (8) exhibit a potent inhibitory effect on rabbit platelet aggregation induced by collagen and thrombin. Those polyhydroxysterols also exhibit a potent inhibitory effect on cyclic AMP phosphodiesterase. Compound 6 with an unusual cyclic enolether exhibit a inhibitory effect on $Na^+,\;K^+$-ATPase.

• Korean Journal of Microbiology
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• v.54 no.2
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• pp.136-139
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• 2018

The inhibitory compound (Compound S) against Ralstonia solanacearum and its conversion product (Compound S') were isolated from the culture filtrate of Bacillus subtilis JW-1 using a series of chromatography procedures. The structures were elucidated as alanyl-L-${\beta}$-(2,3-epoxycyclohexyl-4-one)alanine and alanyl-L-${\beta}$-(2,3-dihydroxycyclohexyl-4-one)alanine, respectively on the basis of nuclear magnetic resonance spectral data, including $^1H$, $^{13}C$, $^1H-^1H$ correlation spectroscopy and heteronuclear multiple bond correlation spectroscopy. The compound S exhibited a broad antimicrobial activity against $G^+$, $G^-$ bacteria, Saccharomyces cerevisiae and Candida albicans. The activity loss of the conversion product revealed that the epoxy function was essential for activity of Compound S.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.259.1-259.1
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• 2003

In the course of hepatoprotective screening for domestic plants. the aerial parts of B. vulgaris var. cycla exhibited hepatoprotective activity which was determined by using the primary cultures of rat hepatocytes injured by H2O2. Bioactivity-guided separation for this plant gave a new flavonoid (1) and the known compounds (2-4), which structures were elucidated by 1H-NMR, HMQC, 1H-1H COSY and HMBC as compound 1, apigenin 8-C-, 7-O-di-$\beta$-D-glucopyranoside, compound 2, vitexin 2"-O-$\beta$-D-glucopyranoside, compound 3, (+)-dehydrovomifoliol, and compound 4, 3-hydroxy-5$\alpha$, 6$\alpha$-epoxy-$\beta$-ionone.

• YAKHAK HOEJI
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• v.51 no.1
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• pp.56-62
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• 2007

Twelve epoxy and hydroxydiosgenin derivatives (DI-1${\sim}$DI-12) were synthesized from diosgenin (25(R)-5-spirosten-3${\beta}$-ol). Diosgenin was epoxidized with m-chloroperoxybenzoic acid (mCPBA) to oxidize 25(R)-4${\alpha}$,5${\alpha}$-epoxyspirostane (DI-1). Diosgenin was reacted with DDQ to form 25(R)-1,4,6-spirostatrien-3-one (DI-2), which was treated with 30% H$_2$O$_2$ to give 25(R)-1${\alpha}$,2${\alpha}$-epoxy-4,6-spirostadien-3-one (DI-3) and treated with mCPBA to form 25(R)-6${\alpha}$,7${\alpha}$-epoxy-1,4-spirostadien-3-one (DI-7), respectively. DI-3 was reduced with NaBH$_4$ to afford 25(R) -1${\alpha}$,2 ${\alpha}$-epoxy-4,6-spirostadien-3${\beta}$-ol(DI-4) and reacted with Li metal in absolute ethanol to form 25(R)-2-ethoxy-1,4,6-spirostatrien-3-one (DI-5). DI-7 was reduced with NaBH$_4$ to produce 25(R)-3${\beta}$,7${\alpha}$-dihydroxy-4-spirostene (DI-8) and treated with Li metal in liquid ammonia to produce 25(R)-7${\alpha}$-hydroxy-4-spirosten-3-one (DI-9). DI-2 was reduced with NaBH$_4$ to form 25(R) -4,6-spirestadien-3${\beta}$-ol(DI-10), which was stirred with 30% H$_2$O$_2$ to synthesize 25(R)-4,6-spirostadien-3-one (DI-11) and reacted with mCPBA to give 25(R)-4${\beta}$,5${\beta}$ -epoxy-6-spirosten-3${\beta}$-ol (DI-12), respectively. The antinociceptive effects of synthesiz ed compounds were measured by hot plate method and compound DI-7 signifcantly exhibited antinociceptive effect. DI-2 decreased the serum triglyceride and total cholesterol levels in poloxamer P-407 injected rat.

• Archives of Pharmacal Research
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• v.28 no.3
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• pp.280-284
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• 2005

The chromatographic separation of the MeOH extract from the aerial parts of Syneilesis palmata led to the isolation of a new sesquiterpene glycoside 4, together with four known compounds. Their structures were characterized to be 4$\beta$,5$\beta$-epoxy-caryophill-8,(15)-ene (1), 3$\beta$­hydroxy-gultin-5-ene (2), 4$\alpha$,5$\beta$-dihydroxy-caryophill-8,(15)-ene (3), (-)-oplopan-4-one-10-$\alpha$-O­$\beta$-D-glucose (4) and 3-hexenyl-1-O-$\beta$-D-glucopyranose (5), based on spectroscopic and chemical methods. Compound 2 showed moderate cytotoxicity against five human tumor cell lines in vitro with its EDso values ranging from 5.90-1 0.83 $\mu$g/mL.

• Archives of Pharmacal Research
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• v.27 no.3
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• pp.291-294
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• 2004

Activity-guided fractionation of the n-hexane and ${CHCl_3}-soluble$ fractions of Sindora sumatrana using a bioassay based on the inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production by inducible nitric oxide synthase (iNOS) in murine macrophage RAW 264.7 cells led to the isolation of the known compound, $(+)-7{\beta}-acetoxy-15,16-epoxy-3$, 13(16), 14-clero-datriene-18-oic acid (2) as an active constituent. In addition, a new trans-clerodane diterpenoid, (+)-2-oxokolavenic acid (1), together with six known compounds, (+)-3, 13-clerodadiene-16,15-olide-18-oic acid (3), $(+)-7{\beta}-acetoxy-3$,13-clerodadiene-16,15-olide-18-oic acid (4), $(+)-7{\beta}-acetoxy-16-hydroxy-3$,13-clerodadiene-16, 15-olide-18-oic acid (5), ${\beta}-caryophyllene$ oxide (6), $clovane-2{\beta},9{\beta}-diol (7),{\;}and{\;}caryolane-1,9{\beta}-diol$ (8) were isolated and found to be inactive. The structure of compound 1 was determined using physical and spectroscopic methods such as 1D and 2D-NMR experiments. The known compounds 2-8 were identified by the spectroscopic data and by comparison with the published values. Of eight isolates (1-8), only compound 2 exhibited an iNOS inhibitory activity with $IC_{50}$/ value of $51.6{\;}\mu\textrm{m}M$.

• Natural Product Sciences
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• v.24 no.2
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• pp.132-138
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• 2018

Phytochemical investigation of 80% MeOH extract of the aerial parts of Capsella bursa-pastoris yielded fourteen compounds (1 - 14). The structures of the compounds were elucidated by spectroscopic methods to be methyl-1-thio-${\beta}$-D-glucopyranosyl disulfide (1), 10-methylsulphinyl-decanenitrile (2), 11-methyl-sulphinyl-undecanenitrile (3), 1-O-(lauroyl)glycerol (4), phytene-1, 2-diol (5), (3S,5R,6S,7E)-5,6-epoxy-3-hydroxy-7-megastigmen-9-one (6), loliolide (7), ${\beta}$-sitosterol (8), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone (9), 1-feruloyl-${\beta}$-D-glucopyranoside (10), pinoresinol-4'-O-${\beta}$-D-glucopyranoside (11), luteolin (12), quercetin-3-O-${\beta}$-D-glucopyranoside (13), and luteolin 6-C-${\beta}$-glucopyranoside (14). Although compound 1 was reported as synthetic compound, 1 was first isolated from natural source. NMR spectral data assignments of 1, 2 and 3 were reported for the first time, and compounds 1 - 14 were for the first time reported from this plant source. The anti-inflammatory effects of 1 - 14 were evaluated in lipopolysaccharide (LPS)-stimulated murine microglia BV-2 cells. Compounds 12 exhibited strong inhibitory effects on nitric oxide production in LPS-activated BV-2 cells with $IC_{50}$ values of $9.70{\mu}M$.

• Natural Product Sciences
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• v.17 no.2
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• pp.85-89
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• 2011

Bioassay-guided fractionation of the $CHCl_3$-soluble fraction of a MeOH extract of the fruiting bodies of Hygrophorus russula led to the isolation of five ergosterol derivatives (1 - 5). The structures of these compounds were identified as ergosterol peroxide (1), ergosta-4,6,8(14),22-tetraen-3-one (2), ergosta-7,22-diene-3${\beta}$,5${\alpha}$,6${\alpha}$-triol (3), ergosta-7,22-diene-3${\beta}$,5${\alpha}$,6${\beta}$,9${\alpha}$-tetraol (4), and 5${\alpha}$,6${\alpha}$-epoxy-ergosta-8(14),22-diene-3${\beta}$,7${\alpha}$-diol (5) by comparing their physicochemical and spectral data with those in the literature. These compounds were evaluated for in vitro cytotoxicity against A549 and XF498 cancer cell lines. Most of the tested compounds, except for compound 3, exhibited moderate cytotoxicity against both A549 and XF498 cell lines with $IC_{50}$ values ranging from 10.2 to 18.3 ${\mu}g/ml$ and from 11.4 to 24.6 ${\mu}g/ml$, respectively.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.159-160
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• 1998

Results of chemistry and biological activity of many years indicate that plants belonging to the Isodon genus are rich in ent-kaurane diterpenoids, which have been revealed to possess biological activities such as antitumor, antibacterial and antiinflammatory effects. In continuation of our research on diterpenoids in medicinal plants of this genus, the acetone extract from the leaves of I. xerophilus, which is a plant native to Yunnan province of China, showed potent antitumor activity against K562. After partition, the most active EtOAc part was studied. Four new diterpenoids named xerophilusin A(l), B(2), C(3), D(4), and eight known compounds including macrocalin B(5) and rabdorosthomin A(6) were isolated, whose structures were elucidated through a series of one- and two-dimensional NMR techniques(DEPT, COSY, HMQC, HMBC and ROESY experiments). Among them, compound 1, 2 and 5 had two unique epoxy units formed by two ether bridges from C-20 to C-7, C-14. Up to now, there are four compounds having such an peculiar structure besides these three compounds. Compound 3 and 4 were two of the few examples possessing $1{\beta}$ substitutes. All the diterpenoid compounds were subjected to the antitumor screening. It is interesting that only xerophilusin A(l), B(2) and macrocalin(5) exhibited significant antitumor activity against K562 by the method of MTT($IC_{50}$ were listed in Table 1.). The results inspired us to infer that the unique ether bridges from C-20 to C-7, C-14 possibly played an important role in the antitumor activity.