• Natural Product Sciences
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• v.10 no.2
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• pp.69-73
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• 2004

Continuation of a phytochemical study of Cichorium intybus L. (Astraceae) growing in Egypt, resulted in the isolation and identification of a new sesquiterpene lactone 3,4-dihydrolactucin, in addition to the eight known compounds; kaempferol, isoscutellarin, cichoriin, umbelliferone, lupeol, lupeol acetate, ${\beta}-sitosterol$, and ${\beta}-sitosterol-3-O-glucoside$. Chemical structures of the isolated compounds were assigned based on different physical, chemical, and spectroscopic techniques including IR, UV, MS, 1D- and 2D-NMR spectra. Furthermore, the antimicrobial, and spasmogenic activities of some fractions and isolates were also assessed.

• YAKHAK HOEJI
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• v.45 no.2
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• pp.147-152
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• 2001

The phytochemical study of the aerial parts of Artemisia sylvatica (Asteraceae) led to the isolation of nine sesquiterpene lactones, l$\alpha$-hydroperoxy-rupicolin A acetate (1), rupicolin B acetate (2), rupicolin A acetate (3), l$\alpha$-hydroxy-4$\alpha$-hydroperoxy-bishopsolicepolide (4), 1$\alpha$-hydroperoxy-4$\beta$-hydroxy-8$\alpha$-acetoxy-guaia-2,9,11 (13)-triene-6$\alpha$,12-oxide (5), 1$\alpha$-hydroperoxy-4$\alpha$-hydroxybishopsolicepolide (6), l$\alpha$,4$\beta$-dihydroxy-8$\alpha$-acetoxy-guaia-2,9,11(13)-triene-6$\alpha$,12-olive (7), rupicolin A (8) and l$\alpha$,4$\alpha$-dihydroxy-bishopsolicepolide (9). Their structures were established by chemical and spectroscopic methods.

• Bulletin of the Korean Chemical Society
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• v.22 no.11
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• pp.1236-1242
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• 2001

(3S,1'S)-3-(1'-Carboxy-2'-phenyl)ethylamino-2-oxetanone (1a) and (3R,1'S)-3-(1'-carboxy-2'-phenyl)ethylamino-2-oxetanone (1b) were designed, synthesized, and evaluated as inhibitors for carboxypeptidase A, a prototypical zinc protease that removes the C-terminal amino acid having an aromatic side chain from oligopeptide substrate. It was concluded from the analysis of inhibition kinetics that while 1a inactivates CPA irreversibly, its diastereoisomer, 1b is a weak competitive inhibitor for CPA. A possible explanation for the observed difference in inhibition mode that is dependent on the inhibitor stereochemistry is offered.

• Journal of the Korean Chemical Society
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• v.7 no.1
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• pp.85-90
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• 1963

The Knoevenagel reaction of fluorinated carbonyl compounds, 1,1,1-trifluoro-propanone-2-heptafluoro-butyraldehyde, 1,3-dichloro-1,1,3,3-tetrafluoro-acetone, tetradecafluoro-heptanone-4 and 2,2,2-trifluoro-acetophenone yielded fluorinated ${\beta},{\beta}$-dialkyl-${\beta}$-hydroxy acids. Dehydration of the acids do not give the olefinic acid in the case of the perfluorinated system and gave a lactone. From the consideration of electronic and steric effects a mechanismic path of the reaction via a carbanion intermediate was proposed for the reaction. Preparation of related derivatives are also described.

• Archives of Pharmacal Research
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• v.4 no.2
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• pp.133-135
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• 1981

Reaction of unsaturated acids with 3-bromo-5, 5-dimenthylhydantoin in dry DMF at room temperature gives bromolactones in 58-91 % yields.

• YAKHAK HOEJI
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• v.37 no.1
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• pp.100-106
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• 1993

Designed system, in which the $\beta$-hydroxy-$\delta$-lactone moiety is connected to benzimdazole ring by ethylene bridge, was propared from 2-sustd. benzimidazole as a potential HMG-CoA reductase inhibitor.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.463-467
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• 1995

In vitro metabolism study of ${\alpha}$-endosulfan by liver and kidney microsomal cytochrome P-450 monooxygenase system of the mouse(Balb/C) was performed. ${\alpha}$-Endosulfan was metabolized to endosulfan lactone(EL), endosulfan hydroxyether(EHE), endosulfan alcohol(EA), endosulfan sulfate(ES), endosulfan ether(EE) and ${\beta}$-endosulfan(${\beta}$-E). The main metabolites of ${\alpha}$-endosulfan were EL(13.2%) and EA(11.5%) in liver microsome and EA(17.4%) md EHE(19.3%) in kidney microsome. The $^{14}C$-activity of organic extractable fraction and water soluble fraction were 63.4% and 31.7% in liver micosome incubates respectively. The water soluble metabolites were EA(83.9%), EHE(4.5%) and ES(2.3). Piperonyl butoxide treatment inhibited the formation of EE by 86%, EA by 92% and EHE, EL and ES were barely formed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.3
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• pp.130-137
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• 2002

Microbial lactonohydrolases (intramolecular ester bond-hydrolyzing enzymes) with unique properties were found. The lactonohydrolase from Fusarium oxysporum catalyzes enantiose-lective hydrolysis of aldonate lactones and D-pantoyl lactone (D-PL). This enzyme is useful for the large-scale optical resolution of racemic PL. The Agrobacterium tumefaciens enzyme catalyzes asymmetric hydrolysis of PL, but the stereospecificity is opposite to that of the Fusarium enzyme. Dihydrocoumarin hydrolase (DHase) from Acinetobacter calcoaceticus is a bifunctional enzyme, which catalyzes not only hydrolysis of aromatic lactones but also bromination of monochlorodi-medon in the presence of H$_2$O$_2$and dihydrocoumarin. DHase also hydrolyzes several linear esters, and is useful for enantioselective hydrolysis of methyl DL-$\beta$-acetylthioisobutyrate and regioselective hydrolysis of methyl cetraxate.

• Archives of Pharmacal Research
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• v.29 no.3
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• pp.203-208
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• 2006

The chromatographic separation of the MeOH extract of the roots of Ainsliaea acerifolia (Compositae) led to the isolation of six known terpenes and two known lignans. Their structures were identified by spectroscopic methods as mokko lactone (1), betulonic acid (2), betulinic acid (3), zaluzanin C (4), $1{\beta}-hydroperoxygermacra-4(15)$, 5, 10(14)-triene (5), pluviatilol (6), (+)-syringaresinol (7), and glucozaluzanin C (8). Compounds $1{\sim}4$ and 8 showed non-specific significant cytotoxicity against five human tumor cell lines with $ED_{50}$ values ranging from $0.36{\sim}5.54{\mu}g/mL$.

• Archives of Pharmacal Research
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• v.24 no.6
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• pp.564-567
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• 2001

The fecal ${\beta}-glucuronidase$ activity of patients with colon cancer and healthy controls were measured to determine the relationship between the fluctuation of intestinal bacterial ${\beta}-glucuronidase$ and colon cancer. The fecal ${\beta}-glucuronidase$ activity of patients with colon cancer was 1.7 times higher than that of the healthy controls. However, when these fecal specimens were sonicated, the enzyme activity of patients with colon cancer was 12.1 times higher than that of the healthy controls. The fecal ${\beta}-glucuronidase$ activity of human Intestinal bacteria was drastically induced by its substrate or the bile secreted after a subcutaneous injection of 1,2-dimethylhydrazine (DMH) and benzo[a]pyrene into rats. DMH-and benzo[a]pyrene-treated biles induced ${\beta}-glucuronidase$ activity in the human intestinal microflora by approximately 1.5- and 2.3-fold, respectively. They also induced ${\beta}-glucuronidase$ in E. coli HGU-3, which is a ${\beta}-glucuronidase$-producing bacterium from the human intestine. D-saccharic acid 1,4-lactone similarly inhibited fecal ${\beta}-glucuronidase$ in several patients with colon cancer in addition to the healthy controls. This suggests that potent ${\beta}-glucuronidase$ activity is a prime factor in the etiology of colon cancer.