[Limonoids from seeds of Azadirachta indica and their antibacterial activity].

Fifteen limonoids were isolated from 95% ethanol extracts of the dry seeds of neem( Azadirachta indica) by various column chromatography techniques including silica gel,Pharmadex LH-20 gel and ODS resin. Based on spectroscopic analysis,their structures were determined as nimbocinol( 1),17ß-hydroxynimbocinol( 2),1α,3α,7α-triacetylvilasinin( 3),7α-benzoyltrichilinin( 4),1,3-diacetyl-7-tigloyl-12-hydroxyvilasinin( 5),3-deacetylsalannin( 6),1-O-acetyl-1-detigloylsalannin( 7),2'( R),3'-dihydrosalannin( 8),2'( S),3'-dihydrosalannin( 9),2,3-dihydronimbolide( 10),6-homodesacetylnimbin( 11),gedunin( 12),7-deacetyl-7-epi-dihydrogedunin( 13),7-deacetoxy-7α-hydroxygedunin( 14) and nimbinene( 15). Compound 7 is a new natural product. 4,8,9,13 and 14 are isolated from the genus Azadirachta for the first time. Compound 2 showed inhibitory activity against Escherichia coli and Staphylococcus epidermidis,with MIC values of 32 and 128 mg·L~(-1),respectively. Compound 10 showed moderate inhibitory activity against S. epidermidis with a MIC value of 64 mg·L~(-1). Compound 11 inhibited the growth of E. coli and Pseudomonas aeruginosa,both with MIC values of 128 mg·L~(-1). Compound 15 exhibited inhibitory activity against P. aeruginosa,with a MIC value of128 mg·L~(-1).

[Limonoids from seeds of Azadirachta indica and their cytotoxic activity].

Eight limonoids were isolated from 95% ethanol extracts of neem(Azadirachta indica) seeds by various chromatographic methods. By comparison of their spectroscopic data with those reported in the literatures, these limonoids were determined as salannin(1), 1-detigloyl-1-isobutylsalannin(2), salannol-3-acetate(3), salannol(4), spirosendan(5), 1-detigloyloxy-3-deacetylsalannin-1-en-3-one(6), nimbin(7) and 6-deacetylnimbin(8). Compounds 2 and 5 were firstly isolated from this genus and 5 represented the only example of its type. And 6 is a new natural product. 6 showed inhibitory activity against HeLa and HL-60 cells, with IC50 of(21.61±4.37) and(27.33±5.74) µmol·L⁻¹, respectively. Both 7 and 8 mildly inhibited the growth of HeLa cells, with IC50 of (33.15±5.24) and (38.56±6.41) µmol·L⁻¹, respectively.

Chemical constituents from branch of Fraxinus sieboldiana.

Using a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, macroporous adsorbent resin, and reversed-phase HPLC, 115 compounds including diterpenes, sesquiterpenes, treterpenes, coumarins, lignans, fatty acid derivatives, and simple aromatic derivatives were isolated from an ethanol extract of branch of Fraxinus sieboldiana (Oleaceaue), and their structures of the compounds were elucidated by spectroscopic methods including 1 D, 2D NMR and MS techniques. Among them, 41 compounds were new. In previous reports, we have been described the isolation, structure elucidation, and bioactivities of the 41 new compounds and 22 known orii including 8 coumarins, 4 phenolic and 12 phenylethanoidal glycosides. As a consequence, we herein reported the isolation and structure elucidation of the remaining 50 known compounds including 8- hydroxy-12-oxoabieta-9(11),13-dien-20-oic 8, 20-lactone(1), 6beta-hydroxyfcrruginol(2),(+)-pisiferic acid(3), (+)-pisiferal(4),(+)-7-dehydroabiet6none(5), 1-oxomiltirone(6), subdigitatone(7), linarionoside B(8), (9S)-linarionoside B(9), (3R,9R)-3-hydroxy-7,8-dihydro-beta-ionol 9-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside(10), ursolic acid(11), betulinic acid(12), euscaphic acid(13), (+)-syringaresinol(14), (+)-fraxiresinol(15), (+)-1-hydroxysyringaresinol(16), pinoresinol(17), medioresinol(18), 8-acetoxypinoresinol(19), epipinoresinol(20), (-)-olivil(21), (+)-cyclo-olivil(22), 3,3'-dimethoxy-4,4',9-trihydroxy-7,9'-epoxylignan-7'-one(23),(+)-1-hydroxypinoresinol 4'-O-beta-D-glucopyranoside (24), (+)-1-hydroxypinoresinol 4"-O-beta-D-glucopyranoside(25),(+)-syringaresinol O-beta-D-glucopyranoside (26), liriodendrin (27), ehletianol D(28), icariside E5(29) (-)-(7R, 8R)-threo-1-C-syringylglycerol(30),(-)-(7R, 8S)-erythro-guaiacylglycerol (31),(-)-(7R, 8R)-threo-guaiacylglycerol(32), 3-(4-beta-D-glucopyranosyloxy-3-methoxy)-phenyl-2E-propenol(33),2,3-dihydroxy-l-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone(34), 2,3-dihydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone (35), 3-hydroxy-l-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone(36), omega-hydroxypropioguaiacone(37), sinapyladehyde(38), trans-p-hydroxycinnamaldehyde(39), syringic acid(40), vanilic acid(41), vanillin(42), 4-hydroxy-benzaldehyde (43), (24R)-24-ethyl-5alpha-cholestane-3beta,5,6beta-triol(44), beta-sitosterol(45), daucosterol(46), 2,6-dimethoxy-I,4-benzoquinone(47), 2,6-dimethoxy-pyran-4-one(48), 1-(beta-D-ribofuranosyl)uracil(49), and mannitol(50). Compouds 1-7,12,18,28-37,44 and 48 were obtained from the genus Fraxinus for the first time.

[Flavonoids from root of Machilus wangchiana].

Twelve flavonoids were isolated from an ethanol extract of Machilus wangchiana by a combination of various chromatographic techniques including column chromatography over silica gel and Sephadex LH-20 and reversed-phase flash chromatography and HPLC. Their structures were identified by spectroscopic data analysis (IR, MS, and NMR) as (+)-catechin (1), (-)-epicatechin (2), 3'-O-methyl-(+)-catechin (3), 3'-O-methyl-(-)-epicatechin (4), 3, 5, 7, 2', 5'-pentahydroxy flavan (5), (-)-naringenin (6), (-)-eriodictyol (7), (-)-liquiritigenin (8), (2R,3R)-(+)-dihydrokaempferol (9), (2R,3S)-(-)-dihydro- kaempferol (10), (2R, 3R)-(+)-taxifolin (11), and quercetin (12). Compounds 1-10 are isolated from the genus Machilus for the first time.

Phenylpropene diglycosides from the bark of Machilus wangchiana.

Five new phenylpropene diglycosides (1-5), together with three known analogs, have been isolated from an ethanol extract of the bark of Machilus wangchiana. Their structures were determined by spectroscopic and chemical methods. In the preliminary assay, compounds 2 and 5-8 reduced dl-galactosamine (GalN)-induced hepatocyte (WB-F344 cells) damage with 37-41% inhibitions at 10 µM.

Butanolide derivatives from the bark of Machilus yaoshansis.

Six new butanolide derivatives with long aliphatic side chains (1-6), together with 23 known lipophilic constituents, were isolated from the bark of Machilus yaoshansis. Their structures were elucidated by spectroscopic and chemical methods. All the isolates were evaluated for cytotoxic and anti-inflammatory activities.

Methoxylated fatty acids from the bark of Fraxinus sieboldiana.

Nine new fatty acid derivatives, including seven methoxylated (1, 2, and 4-8) and two hydroxylated (3 and 9) fatty acids, have been isolated from the ethanol extract of the stem bark of Fraxinus sieboldiana. Their structures were determined by spectroscopic methods including IR, MS, 1D, and 2D NMR experiments. The 3- or 9-methoxylated fatty acids are reported for the first time in nature.

Minor new constituents from Heteroplexis micocephala.

By using a combination of various chromatographic techniques including column chromatography over silica gel and Pharmadex LH-20 and reversed-phase HPLC, two minor new compounds, labda-12, 14-dien-6beta, 7alpha, 8beta, 17-tetraol (1), 2, 3-cis-6-acetyl-5-hydroxy-2-(hydroxymethylvinyl)-2, 3-dihydrobenzofuran-3-ol angelate (2), and a minor new natural product 6-methoxy-4-methyl-3, 4-dihydro-2H-naphthalen-1-one (3) have been isolated from an ethanolic extract of Heteroplexis micocephala. Their structures were elucidated with spectroscopic data analysis including 2D NMR experiments.