• Archives of Pharmacal Research
• /
• 제27권10호
• /
• pp.1020-1022
• /
• 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.

• Journal of Microbiology and Biotechnology
• /
• 제21권9호
• /
• pp.930-936
• /
• 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
• /
• 제14권4호
• /
• pp.233-238
• /
• 2008

The aerial parts of Epimedium koreanum Nakai have been used to stimulate hormone secretion in treating impotence. Ten flavonol glycosides, 3,4,5-trihydroxy-8-prenylflavone 7-O-[${\beta}$-D-glucopyranosyl($1{\rightarrow}2$)-${\beta}$-D-glucopyranoside] (1), hyperoside (2), icarisid II (3), 2"-O-Rhamnosylicarisid II (4), epimedin A (5), epimedin B (6), epimedin C (7), icariin (8), hexandraside E (9), and epimedoside A (10) were isolated from the an ethylacetate soluble extracts of the aerial parts of Epimedium koreanum Nakai through activity-monitord fractionation and isolation method. The structures of compounds 1 - 10 were elucidated by high resolution fast atom bombardment mass spectrometry and two dimentional nuclear magnetic resonance spectroscopy analysis. Compounds 1 and 4 showed potent antioxidant activity, with $IC_{50}$ values of 19.7 and 11.5 ${\mu}g$/mL and 88.2 and 90.5 ${\mu}M$, respectively.

• 한국환경농학회지
• /
• 제15권2호
• /
• pp.167-178
• /
• 1996

전보에서 대두(大豆)와 벼의 현탁배양세포(懸濁培養細胞)에서 생성된 PCP의 주요 수용성대사물은 PCP를 비롯한 여러 종류의 염화페놀과 glucose간 ${\beta}-linkage$로 연결된 ${\beta}-glucoside$ 구조를 가질 것으로 추정한 바 있다. 본 연구에서는 conjugates를 가수분해시키지 않는 조건에서 기기적인 방법으로 그 구조를 확인하고자 하였다. Acetyl화(化) 한 glucose conjugates는 aglycones 분석에서 예상한 대로 3종류 이상이 존재하는 것으로 확인할 수 있었으며, 충분히 정제한 각각의 acetyl화(化) 대사물을 FAB-MS로 분석한 결과 분자량과 aglycones part와 관련된 특징적 spectral data 등 conjugates 구조 확인에 필수적인 정보를 얻을 수 있었다. 이러한 구조적 정보와 지금까지의 연구 결과, 즉 현탁배양초기에 생성된 PCP의 glucose conjugates는 ${\beta}-glucosidase$에 의해 특징적으로 가수분해되고, aglycones이 PCP 외에도 tetrachlorophenol 및 tetrachlorocatechol 등이라는 사실을 종합할 때 현탁배양에서 생성된 conjugates는 주로 pentachlorophenyl ${\beta}-D-glucopyranoside$, tetrachlorophenyl ${\beta}-D-gluco$ pyranoside 및 2-hydroxy-3,4,5,6-tetrachlorophenyl ${\beta}-D-glucopyranoside$인 것으로 확인할 수 있었다.