• Natural Product Sciences
• /
• v.16 no.3
• /
• pp.148-152
• /
• 2010

Microbial metabolism studies of yangonin (1), a major styryl lactone from Piper methysticum, have resulted in the production of three hydroxylated metabolites (2-4). The chemical structures of these compounds were elucidated to be 4-methoxy-6-(12-hydroxystyryl)-2-pyrone (2),4-methoxy-6-(11,12-dihydroxystyryl)-2-pyrone (3),and 4,12-dimethoxy-6-(7,8-dihydroxy-7,8-dihydrostyryl)-2-pyrone (4) on the basis of the chemical and spectroscopic analyses. The compounds 3 and 4 are reported herein as microbial metabolites of yangonin for the first time.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.19 no.5
• /
• pp.1375-1378
• /
• 2005

Sequiterpene lactone (1) has determined by spectroscopic analysis. This compound (1) inhibited the growth of the dermatophytic fungus Trichophyton mentagrophytes (ATCC 28185, 2 mm zone at $15{\mu}g/disk$), cytotoxic to murine leukaemia cell lines ATCC CCL 46 P388Dl, ($IC_{50}$ 1,125 ng/mL at $7.5{\mu}g/disk$) and BSC monkey kidney cell lines (100% of well at $15{\mu}g/disk$).

• Bulletin of the Korean Chemical Society
• /
• v.24 no.7
• /
• pp.921-924
• /
• 2003

Homochiral (-)-pipecolaldehyde 6 from D-glucono- δ-lactone underwent a highly diastereoselective addition upon treatment with vinylmagnesium bromide. Treatment with vinylmagnesium bromide produced antiaminoalcohol 7a which was easily converted into the synthesis of 1,6-diepicastanospermine 2.

• Archives of Pharmacal Research
• /
• v.27 no.10
• /
• pp.1016-1019
• /
• 2004

The chromatographic separation of a methylene chloride extract of Artemisia rubripes led to the isolation of a new sesquiterpene lactone (3), together with four known compounds, a coumarin (2) and three terpenes (1, 4, and 5). Their structures were characterized to be $1{\beta},6{\alpha}$- dihydroxy-4(15)-eudesmene (1), scopoletin (2), $1{\alpha},4{\beta}-dihydroxy-8{\alpha}$-acetoxy-guaia-2,10(14), 11(13)-triene-6,12-olide (3), $1{\alpha},4{\beta}$ -dihydroxy-8${\alpha}$-acetoxy-guaia-2,9,11(13)-triene-6,12-olide (4), and $\beta$ -sitosterol-3-O-${\beta}$-D-glycoside (5) by spectroscopic means.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1995.04a
• /
• pp.60-60
• /
• 1995

새로운 혈소판 활성화인자 (PAF) 수용체 결합 저해활성 유효성분인 pinusolide ($IC_{50}$/=2.5$\times$$10^{-7}$M)와 arctigenin($IC_{50}$/=5.2$\times$$10^{-6}$M)을 측백엽(Biota orientalis)과 우방자(Arctium lappa)로부터 분리하여 이미 보고한 바 있다. PAF 수용체에 대한 구조활성 상관관계를 규명하고자 또한 용해도가 우수한 강력한 PAF 길항제를 개발하고자 이 길항제들의 유도체들을 다양한 유기화학반응을 이용하여 합성하였고 in vitro PAF receptor binding assay로 그 활성의 강도를 비교 검토하였다. 그 결과, lactone ring 부분은 unsaturated lactone이 saturated lactone보다 활성이 강하였고 ring이 개열되면 활성이 현저히 감소하였다. pinusolide 경우 exocylclic double bond 부분은 sp$^2$구조의 hydrophobic한 유도체가 활성이 강하였으며, methyl ester 부분은 hydrophobic한 유도체가 활성이 강하였다. Arctigenin의 경우 aromatic unit가 hydrophobic할수록 활성이 강하였다.

• Korean Journal of Microbiology
• /
• v.44 no.2
• /
• pp.85-92
• /
• 2008

Pseudomonas aeruginosa is an opportunistic human pathogen, causing a wide variety of infections including cystic fibrosis, microbial keratitis, and burn wound infections. The cell-to-cell signaling mechanism known as quorum sensing (QS) plays a key role in these infections and the QS systems of P. aeruginosa have been most intensively studied. While many literatures that introduce the QS systems of P. aeruginosa have mostly focused on two major acyl-homo serine lactone (acyl-HSL) QS signals, N-3-oxododecanoyl homoserine lactone (3OC12) and N-butanoyl homoserine lactone (C4), several new signal molecules have been discovered and suggested for their significant roles in signaling and virulence of P. aeruginosa. One of them is PQS (Pseudomonas quinolone signal; 2-heptyl-3-hydroxy-4-quinolone), which is now considered as a well-characterized major signal meolecule of P. aeruginosa. In addition, recent researches have also suggested some more putative signal molecules of P. aeruginosa, which are diketopiperazines (DKPs) and pyocyanin. DKPs are cyclic dipeptides and structurally diverse depending on what amino acids are involved in composition. Some DKPs from the culture supernatant of P. aeruginosa are suggested as new diffusible signal molecules, based on their ability to activate Vibrio fischeri LuxR biosensors that are previously considered specific for acyl-HSLs. Pyocyanin (1-hydroxy-5-methyl-phenazine), one of phenazine derivatives produced by P. aeruginosa is a characteristic blue-green pigment and redox-active compound. This has been recently suggested as a terminal signaling factor to upregulate some QS-controlled genes during stationary phase under the mediation of a transcription factor, SoxR. Here, details about these newly emerging signaling molecules of P. aeruginosa are discussed.

• Archives of Pharmacal Research
• /
• v.14 no.2
• /
• pp.143-146
• /
• 1991

A new synthetic sequence for the chiral lactone moiety of compactin was developed from $\alpha$-D-glucose in 9 steps via simultaneous reductive detosylation and epoxide-ring opening of 2, 3-epoxy-4-tosylate using NaBH_4$ to afford 2, 4-dideoxy sugar as a key intermediate.

• Korean Journal of Pharmacognosy
• /
• v.17 no.1
• /
• pp.7-11
• /
• 1986

The young leaf of Perilla species was cultured by two stage culture system using the medium containing mevalonic acid lactone. The growth rate and productivity of essential oil of callus were increased. The essential oil from intact plant and callus was also analysed. Sesquiterpene hydrocarbons and one sesquiterpene alcohol were identified in essential oils of callus.

• Archives of Pharmacal Research
• /
• v.24 no.5
• /
• pp.416-417
• /
• 2001

A new triterpene lactose named patrinolide A (7) has been isolated from the roots of Patrinia scabiosaefolia (Valerianaceae). Its structure was determined to be 11$\beta$,21$\beta$-dihydroxy-3-oxooleanan-28,13$\beta$-olide on the basis of spectral analysis, including 2D-NMR techniques.

• Natural Product Sciences
• /
• v.9 no.1
• /
• pp.28-30
• /
• 2003

A sesquiterpene lactone, 1-O-acetyl-4R,6S-britannilactone (1) which has a new stereochemistry was isolated from the flowers of Inula britannica L. var.chinensis (Rupr.) Reg. Its stereostructure was determined by a x-ray crystallography.