• 생약학회지
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• 제31권4호
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• pp.434-437
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• 2000

Two sinapic acid esters were isolated from the methanol extract of Raphani Semen. The structures were elucidated on the basis of spectroscopic methods $(^1H-NMR,\;^{13}C-NMR,\;HMQC,\;^1H-^1H\;COSY\;and\;HMBC)$ and were identified as methyl sinapate (1) and ${\beta}-D-(3-O- sinapoyl)fructofuranosyl-{\alpha}-D-(6-O-sinapoyl)glucopyranoside$ (2). Compound 1 was first isolated from the genus of Raphanus.

• Natural Product Sciences
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• 제27권2호
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• pp.122-127
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• 2021

A new steroidal saponin, (23S,24S)-spirosta-5,25(27)-diene-1𝛽,3𝛽,23,24-tetrol 1-O-((2,3-diacetyl-α-L-rhamnopyranosyl)-(1→2)-[𝛽-D-xylopyranosyl-(1→3)]-α-L-arabinopyranoside)-24-O-𝛽-D-glucopyranoside (humilisoside) together with the known 𝛽-sitosterol 3-O-glucopyranoside, adenosine, dioscin, and methylprotodioscin were isolated from the leaves of Dracaena humilis. Their structures were elucidated by spectral techniques including mass spectrometry (ESIMS, HRESIMS, tandem MS-MS), 1D NMR (¹H, ¹³C NMR), 2D NMR (HSQC, ¹H-¹H COSY, HMBC, NOESY), chemical method as well as by comparison with spectroscopic data reported in the literature. The chemotaxonomic significance of the isolation of these compounds is discussed. This is the first report on the phytochemical investigation of D. humilis.

• 미생물학회지
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• 제54권2호
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• pp.136-139
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• 2018

풋마름병 균에 대해 강한 저해활성을 갖는 활성물질 Compound S와 conversion product인 compound S'이 Bacillus subtilis JW-1 배양액에서 일련의 크로마토그래피 방법으로 분리 정제되었고, $^1H$ NMR, $^{13}C$ NMR, $^1H-^1H$ COSY와 HMBC 등의 spectra 분석에 의해 구조가 alanyl-L-${\beta}$-(2,3-epoxycyclohexyl-4-one)alanine와 alanyl-L-${\beta}$-(2,3-dihydroxycyclohexyl-4-one) alanine로 각각 동정되었다. Compound S는 $G^+$, $G^-$ bacteria, yeast와 Candida albicans 등에 대해 광범위한 antimicrobial activity를 나타내며, conversion product의 활성 상실을 통해 intact oxirane ring이 Compound S의 활성에 필수적임이 밝혀졌다.

• Natural Product Sciences
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• 제28권1호
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• pp.1-5
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• 2022

Two 2H-1-benzopyran derivatives, methyl 8-hydroxy-2,2-dimethyl-2H-1-benzopyran-5-carboxylate (1) and methyl 8-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carboxylate (2), including a new compound (1) were isolated from the twigs of Chaenomeles sinensis. Their chemical structures were characterized based on analysis of NMR data including ¹H and ¹³C, COSY, HSQC, and HMBC and HRMS data. The isolated compounds (1 and 2) were assessed for their anti-neuroinflammatory activity by measuring inhibition levels of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 cells and for their neurotrophic activity by the secretion of nerve growth factor (NGF) in C6 cells. Compounds 1 and 2 exhibited powerful anti-neuroinflammatory effects with IC₅₀ values of 17.14 and 19.30 μM, respectively, without cell toxicity, and also showed moderate effects on the stimulation of NGF secretion levels with 113.15 ± 3.54 and 130.20 ± 8.03%, respectively. The biosynthetic pathway of 1 and 2 was proposed that they would be derived from a protocatechuic acid and an isoprenyl unit.

• 한국자기공명학회논문지
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• 제10권2호
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• pp.163-174
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• 2006

Luteinizing Hormone Releasing Hormone(LHRH) is a decapeptide neurotransmitter known to be regulated by metal ions in the hyperthalamus. Zn-binding LHRH complex was systhesized, and zinc-LHRH complex was studied to understand what kinds of structural modifications would be critical in the LHRH releasing mechanism. Both nonexchangeable and exchangeable $^1H-NMR$ signal assignments were accomplished by pH-dependent and COSY NMR experiments. In addition, $^1H-NMR$ chemical shift changes of a-proton and peptide NH NMR signals at different pH condition, and $^1H-NMR$ signal differences between metal free and metallo-LHRH complex was monitored. NMR signals exhibit that primary metal-binding sites are nitrogens donor of imidazole ring and Arg, and peptide oxygen of Pro-His in the sequence. Structure obtained in this study has a cyclic conformation which is similar to that of energy minimized, and exhibits a specific a-helical turn with residue numbers $(2{\sim}7)$ out of 10 amino acids.

• Applied Biological Chemistry
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• 제46권2호
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• pp.144-149
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• 2003

산철쭉 끝을 MeOH로 추출하고, 이를 EtOAc, n-BuOH과 $H_2O$로 분배 추출하였다. EtOAc추출물과 n-BuOH 추출물에 대하여 silica gel과 ODS column을 이용하여 chromatography하거나, 아세틸화 한 후 sillica gel column chromatography를 수행하여 2종의 triterfenoid와 3종의 diterpenoio를 분리하였다. 각 화합물은 $^1H-^lH\;COSY$, HMQC, HMBC와 같은 2D-NMR기법을 포함한 스펙트럼 데이터를 해석하여 $2{\alpha}\;3\{beta}-dihydroxylolean-12-ene (1), ursolic acid (2), grayanotoxin IV (3), grayanotoxin I (4) 및 grayanotoxin III (5) 등으로 동정하였다.

• Natural Product Sciences
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• 제17권4호
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• pp.350-353
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• 2011

A new daucosteryl derivative, verticilloside (1), was isolated from the seeds of Malva verticillata L. (Malvaceae). The structure was determined to be 3-O-[${\beta}$-D-(6'-linoleoyl)glucopyranosyl]-${\beta}$-sitosterol based on spectroscopic analyses ($^1H$ and $^{13}C$-NMR, DEPT, COSY, HMQC, and HMBC) and chemical reactions.

• 분석과학
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• 제9권1호
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• pp.112-117
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• 1996

이탈리안 라이그라스(Lolium multiflorum Lam.) 및 버뮤다그라스와 같은 벼과 잡초에 병해를 일으키는 Bipolaris cynodontis의 배양 추출물로부터 이탈리안 라이그라스 뿌리의 생육저해를 나타내는 3종류의 활성물질을 분리 정제하고 $^1H$, $^{13}C$ 및 2차원 NMR을 포함한 각종 기기분석방법을 통하여 이들 화함물들의 구조를 결정하였다. 이들 화합물들은 저자에 의하여 보고된 바 있는 cochlioquinol이라 명명된 화합물의 유도체들로서 지금까지 보고된 바 없는 새로운 물질이며 숙주식물 중의 하나인 이탈리안 라이그라스에 대하여 활성(20~70%)을 나타내는 것으로 보아 병원균의 병징 발현에 관여하는 것으로 보여진다.

• Journal of Microbiology and Biotechnology
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• 제5권1호
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• pp.36-40
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• 1995

Valistatin, a new inhibitor of aminopeptidase M(AP-M) was discovered in the culture broth of Streptomyces sp. SL20209 isolated from a soil sample. The inhibitor was purified by extraction with n-butanol and the various column chromatographies, and then isolated as whitish powder. The $^1 H-and ^1 H, ^1 H-COSY$ NMR studies, amino acid analysis, and fragmentation patterns by FAB-MS suggested the presence of one 3-amino-2-hydroxy-4-phenylbutanoic acid and two valine residues in the inhibitor. Thus, the structure of valistatin was determined as 3-amino-2-hydroxy-4-phenylbutanoyl-valyl-valine. Valistatin has the molecular formular $C_20H_31N_3 O_5$ (MW 394), and its $IC_50$ value against hog kidney AP-M was determined to be 3.12 $mu g/ml$.

• Bulletin of the Korean Chemical Society
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• 제27권1호
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• pp.93-98
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• 2006

Two new compounds 1'-(stigmast-11,20(21),25-trien 3$\alpha$,9$\alpha$-diolyl)-3'-(pimara-11,15-dien-3$\alpha$-olyl) glycerol (1) and stigmast-5-en-3$\alpha$,26-diol (2) along with known fatty acids n-hexacosanoic acid (3) and hexadecanoic acid (4), have been isolated from the methanol extract of rice hulls of Oryza sativa. The structures of the compounds were elucidated using 1D and 2D NMR spectral methods, viz; $^1H, ^{13}C, ^{13}C$-DEPT, $^1H-^1H$ COSY, $^1H-^{13}C$ HETCOR, HSQC and HMBC aided by IR, EIMS, FABMS and HRFABMS. Compound (1) showed inhibition to radish germination, growth of shoot and root length.