• KSBB Journal
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• v.18 no.6
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• pp.511-516
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• 2003

The methanol extract from leaves of Catalpa ovata 6. DoN showed DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging activity, and its antioxidative compounds were studied. The ethyl acetate-soluble neutral fraction from the methanol extract was successively purified with silica gel adsorption column chromatography, Sephadex LH-20 column chromatography and HPLC. Three antioxidative compounds were isolated and identified as piperitol, pinoresinol and lariciresinol by HR-MS and NMR spectroscopic analyses. The DPPH radical-scavenging activity of the identified compounds decreased in the order of lariciresinol > pinoresinol > piperitol.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.739-741
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• 2009

• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1233-1235
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• 2005

Two new biflavonoids, 3'-hydroxyamentoflavone-7-O-methyl ether (1) and 3'-hydroxyamentoflavone (2), were isolated from the fruits of Aristolochia contorta Bge. Their structures were elucidated by HR-ESI-MS, 1D-, and 2D-NMR spectroscopy.

• Natural Product Sciences
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• v.24 no.1
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• pp.54-58
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• 2018

A phytochemical investigation of Allium macrostemon Bunge (Liliaceae) afforded the new pregnane steroidal glycoside, named allimacroside F (1), along with three known glycosides, benzyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (2), phenylethyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (3), (Z)-3-hexenyl-O-${\alpha}-{\text\tiny{L}}$-rhamnopyranosyl-($1{\rightarrow}6$)-${\beta}-{\text\tiny{D}}$-glucopyranoside (4). The identification and structural elucidation of a new compound (1) was carried out based on spectral data analyses ($^1H-NMR$, $^{13}C-NMR$, $^1H-^1H$ COSY, HSQC, HMBC, and NOESY) and HR-FAB-MS.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1020-1022
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• 2004

A new ceramide alomacrorrhiza A was isolated from the ethanolic extract of the plant Alocasia macrorrhiza (L.) Schott. Its chemical structure was elucidated as (2S,3S,4R)-2N-[(2'R)-2'- hydroxy-hexacosanoyl]-tetradecane-1,3,4-triol based on extensive 1D, 2D NMR, EI-MS, FABMS, HR-FAB-MS spectroscopic data and chemical degradation studies.

• Natural Product Sciences
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• v.19 no.4
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• pp.342-346
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• 2013

A new apotirucallane-type triterpenoid, $3{\alpha}$-tigloylsapelin D (1) together with five known triterpenoids such as meliasenin B (2), sendanolactone (3), (-)-$12{\beta}$-hydroxykulactone (4), cinamodiol (5), and $3{\alpha}$-hydroxytirucalla-7,24(25)-dien-6-oxo-21,16-olide (6) were isolated from the fruits of Melia azedarach. Their structures were established on the basis of various NMR spectroscopic analyses including 2D-NMR techniques (HSQC, HMBC, and NOESY) and HR-FAB-MS data.

• Natural Product Sciences
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• v.29 no.1
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• pp.17-23
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• 2023

A phytochemical investigation of the fruits extract of Melia toosendan afforded the isolation of two new nor-neolignans, meliasendanins E (1) and F (2), as well as twelve known compounds (3 - 14) using various separation technique such as Diaion HP20, silica, RP-18 gel column chromatography and semi-preparative HPLC. Their chemical structures were elucidated by extensive NMR spectroscopic data including 2D-NMR, and HR-ESI-MS as well as ECD data. Among the twelve known compounds, the absolute structures of 3 - 6 were determined first, and given the trivial names as meliasendanins G-J (3 - 6). Based on the evaluation of anti-inflammatory activity, compounds 7 - 8 exhibited inhibitory effects on LPS-induced nitric oxide production in RAW 264.7 macrophages with IC₅₀ values of 34.6 and 39.5 µM, respectively.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.930-936
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• 2011

Two new cyclic depsipeptides wewakamide A (1) and guineamide G (2) have been isolated from the marine cyanobacterium Lyngbya semiplena and Lyngbya majuscula, respectively, collected from Papua New Guinea. The amino and hydroxy acid partial structures of wewakamide A and guineamide G were elucidated through extensive spectroscopic techniques, including HR-FABMS, 1D $^1H$ and $^{13}C$ NMR, as well as 2D COSY, HSQC, HSQC-TOCSY, and HMBC spectra. The sequence of the residues of wewakamide A was determined through a combination of ESI-MS/MS, HMBC, and ROESY. Wewakamide A possesses a ${\beta}$-amino acid, 3-amino-2-methylbutanoic acid (Maba) residue, which has only been previously identified in two natural products, guineamide B (3) and dolastatin D (4). Although both new compounds (1,2) showed potent brine shrimp toxicity, only guineamide G displayed significant cytotoxicity to a mouse neuroblastoma cell line with $LC_{50}$ values of 2.7 ${\mu}M$.

• Natural Product Sciences
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• v.25 no.4
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• pp.354-357
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• 2019

Toxicodendron vernicifluum, also called as Rhus verniciflua is a deciduous tree belonging to Anacardiaceae family. Two new caffeoyl threonate esters, rhuseols A (1) and B (2), together with 5-O-(E)-caffeoylquinic acid methyl ester (3) were isolated from the leaves of T. vernicifluum. The structures of isolated compounds were established by using 1D and 2D NMR in combination with HR-ESI-MS. Compounds 1 - 3 showed DPPH radical scavenging effects with IC₅₀ values of 47.9, 107.8 and 15.4 μM, respectively. Taken together, these compounds might contribute to the antioxidant properties of the leaves of T. vernicifluum, which will be useful for various oxidative stress mediated diseases.

• Journal of Microbiology and Biotechnology
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• v.26 no.1
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• pp.56-60
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• 2016

Two new glucosides (1 and 2) of geldanamycin (GA) analogs were obtained from in vitro glycosylation by UDP-glycosyltransferase (YjiC). Based on spectroscopic (HR-ESI-MS, 1D, and 2D-NMR) analyses, the glucosides were elucidated as 4,5-dihydro-7-O-descarbamoyl-7-hydroxyl GA-7-O-β-D-glucoside (1) and ACDL3172-18-O-β-D-glucoside (2). Furthermore, the water solubility of compounds 1 and 2 was about 215.2 and 90.7 times higher respectively, than that of the substrates. Among compounds 1-4, only 3 showed weak antiproliferative activity against four human tumor cell lines: MDA-MB-231, SMMC7721, HepG2, and SW480 (IC₅₀: 13.6, 15.1, 31.8, and 22.7 μM, respectively).