• Journal of the Korean Magnetic Resonance Society
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• v.10 no.2
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• pp.188-196
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• 2006

A known theonellapeptolide Ie, previously reported in other research group, was isolated from the methanolic extract of the Philippine sponge Theonella swinhoei. The planar structure of this compound was determined on the basis of NMR methods including HMBC and selective HMBC experiments. This is fast and efficient for the dereplication of natural products compared with the MS studies of fragments obtained from complete and partial hydrolysis. The sequence of thirteen amino acids including six N-methyl amino acids in the compound was clearly determined from correlations of extensive HMBC experiments.

• Korean Journal of Pharmacognosy
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• v.31 no.1
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• pp.34-38
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• 2000

Three compounds were isolated from the roots of Astragalus membranaceus (Leguminosae). On the basis of spectroscopic evidences, the structures were characterized as $3-0-{\beta}-D-xylopyranosyl-(2',3'-O-diacetyl)-6-0-{\beta}-D-glucopyranosyl-3{\beta},6{\alpha},16{\beta},25-tetrahydroxy-20(R)$,24(S)-epoxy-cycloartane(Astragaloside I), $3-0-{\beta}-D-xylopyranosyl-(2'-O-acetyl)-6-0-{\beta}-D-glucopyranosyl-3{\beta},6{\alpha},16{\beta},25-tetrahydroxy-20(R)$,24(S)-epoxy-cycloartane(Astragaloside II), $3-0-{\beta}-D-xylopyranosyl-(2',4'-O-diacetyl)-6-0-{\beta}-D-glucopyranosyl-3{\beta},6{\alpha},16{\beta},25-tetrahydroxy-20(R)$,24(S)-epoxycycloartane(Isoastragaloside I). Full data of NMR including HMBC and 1D-TOCSY experiment of these compounds were reported for the first time.

• Korean Journal of Pharmacognosy
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• v.30 no.4
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• pp.417-419
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• 1999

$Three\;compounds-ethyl-{\beta}-D-glucopyranoside$, 1,2,3,7-tetramethoxyxanthone, 1,7-dimethoxyxanthone-were isolated from roots of Polygala tenuifolia. The structures of these compounds were establised on the basis of spectral evidence including 2D NMR and HMBC studies. $Ethyl-{\beta}-D-glucopyranoside$ was isolated for the first time from Polygala genus and HMBC data of these compounds were first reported.

• Archives of Pharmacal Research
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• v.19 no.4
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• pp.302-306
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• 1996

The $^1H- and^{13}C-NMR$ spectra of alaternin, aurantio-obtusin, chryso-obtusin, obtusin and 2-glucosyl obtusifolin isolated from the seeds of Cassia tora have been assigned based on HMBC, long-range HETCOR, fully $^1H-coupled {13}^C-NMR$, deuterium isotope experiment, and by comparison with the model compounds.

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.284-286
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• 1994

A guaian type sesquiterpene, torilin, was isolated from the hexane extract of the fruits of Torilis japonica. The $^1H{\;}and{\;}^{13}C-sinals$ of this compound have been fully assigned utilizing $^1H-^1H$ COSY, HMQC, and HMBC experiments.

• Journal of Ginseng Research
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• v.19 no.1
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• pp.45-50
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• 1995

(20S)- and (20R)-protopanaxadiol were prepared from crude ginseng saponin by chemical treatment. The $^{1}H$- and $^{13}C$-NMR signals of these compounds were fully assigned by various NMR techniques such as DEPT, 1H-1H COSY, HMQC, HMBC and NOESY.

• Journal of Life Science
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• v.9 no.2
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• pp.207-211
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• 1999

Biologically active compounds in Polygonatum sibiricum were extracted using organic solvents as hexane, CHCl$_3$, n-butanol corresponding each component. Compound I was purified from hexane layer and the chemical structure of compound I was characterized using 1H-NMR, 13C-NMR, DEPT135, COSY, HMQC, HMBC spectrum and MS-spectrum. Consequently, the chemical structure of compound I was determined as 9,12-(9E,l2E)-octade cadienoic acid.

• Journal of Life Science
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• v.9 no.2
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• pp.212-215
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• 1999

Biologically active compounds in Polygonatum sibiricum were extracted using organic solvents as hexane, CHC1$_3$, n-butanol corresponding each component. Compound II was purified from hexane layer and the chemical structure of compound II was characterized using IH-nmr, 13C-nmr, DEPT135, COSY, HMQC, HMBC spectrum and MS-spectrum. Consequently, the chemical structure of compound II was determined as 2-Hydroxy-3-(9,12-(9E,12E)-Octadecadienoyloxy) propanoic acid.

• Natural Product Sciences
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• v.12 no.1
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• pp.62-66
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• 2006

A steroidal saponin, $3-O-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)-[{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}3)]-{\beta}-D-glucopyranosylpennogenin$ ;(1, spiroconazole A) was isolated from the tubers of Dioscorea bulbifera L. var sativa and $^1H-and\;^{13}C-NMR$ assignment was completed using HMBC correlation. In addition, four phenolic substances, 2,7-dihydroxy-4-methoxyphenanthrene (2), quercetin (3), $quercetin-3-O-{\beta}-D-glucopyranoside$ (4), and $quercetin-3-O-{\beta}-D-galactopyranoside$ (5) were also isolated.

• Journal of the Korean Chemical Society
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• v.38 no.2
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• pp.169-173
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• 1994

The previously reported cytotoxic metabolites, against the KB cell line, xestoquinone, halenaquinol sulfate and $halenaquinol^{5,6}$ were isolated from the unidentified sponge collected in October 1992, Manado Bay, Sulawesi in Indonesia. Their structure were elucidated by $^1H-,\;^{13}C$-NMR, $^1H-,\;^{13}C$(1 bond) Heteronuclear Multiple Quantum Coherence Spectroscopy$(HMQC)^1$, $^1H-,\;^{13}C$C(2 and 3 bond) Heteronuclear multiple Bond Correlation Spectroscopy$(HMBC)^2$, Electron Impact Mass Spectroscopy(EI ms), Ultraviolet Spectroscopy(UV), and Infrared Spectroscopy(IR)