• Journal of the Korean Chemical Society
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• v.43 no.4
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• pp.447-455
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• 1999

Allyl (5R)-(Z)- and (5R)-(E)-6-[(2S)-2,3-isopropylidenedioxypropylidene]Penicillanate(10a and 10b) were prepared from allyl (5R)-dibromopenicillanate(6) via a sequence of reactions involving condensation with 2,3-O-isopropylidene-D-glyceraldehyde, reduction with $Zn-NH_4OAc$, and Mitsunobu elimination. Deprotection of isopropylidene and allyl groups of 10a gave potassium (5R)-(Z)-6-[(2S)-2,3-dihydroxypropylidene]penicillanate(4). However, deprotection of isopropylidene group of 10b afforded ${\alpha},\;{\beta}$-unsaturated-lactone(12). Allyl (5R)-(Z)- and (5R)-(E)-6-[(2S)-2-(t-butyldimethlsilyloxy)propylidene]penicillanate(18a and 18b) were prepared from ally (5R)-dibromopenicillanate(6) via a sequence of reactions involving condensation with (2S)-2-(t-butyldimethylsilyloxy)propanal(15), reduction with $Zn-NH_4OAc$ and Mitsunobu elimination or mesylation-elimination. Deprotection of t-butyldimethylsilyl and allyl groups of 18a and 18b gave potassium (5R)-(Z)- and (5R)-(E)-6-[(2S)-2-hydroxypropylidene]penicillanate(5a and 5b), respectively.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.19-27
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• 1996

Zanthoxylum piperitum and Z. schinifolium have been utilized not only as food stuffs, but also as medicinal plants in Korea. In this study, lipids, sugar, amino acids and other components of Zanthoxylum piperitum and Z. schinifolium peels and seeds were analyzed by HPLC and GLC. Four samples contained common fatty acids such as linoleic, linolenic, palmitic, oleic and stearic acid. The contents of unsaturated fatty acids were 87.1% and 64.8% in Z. schinifolium peels and seeds, 73.6% and 62.9% in Z. piperitum peels and seeds, respectively. Z. schinifolium peels contained only beta-sitosterol, whereas other three samples contained campesterol, stigmasterol and beta-sitosterol. In case of free amino acids, peels of both species showed higher contents of acids than seeds of both species. Glutamic acid, aspartic acid, arginine, valine, and leucine were found in all four samples. Essential oils consisted of limonene (30.1-66.8%), beta-phellandrene (4.8-13.3%), citronellal (1.5-22%) and cineol (1.6-3.9%). It is worthwhile to note that the content of citronellal in Z. schinifolium seeds was higher than that of the others.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.392-395
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• 2014

(2S,3S,4S)-3,4-Dihydroxyglutamic acid (DHGA), a biologically active ${\alpha},{\beta}$-dihydroxy-${\gamma}$-amino acid, was efficiently synthesized from a readily available D-serine derivative in 30% overall yield over 11 steps. The key stereoselective $OsO_4$-catalyzed dihydroxylation reaction controlled by an N-diphenylmethylene group on the amino group of ${\gamma}$-amino-${\alpha},{\beta}$-unsaturated (Z)-ester successfully introduced the diol moiety of the intermediate 5a in 86% with more than 10 : 1 diastereomeric ration. Then it was in turn successfully converted to the desired target compound, (2S,3S,4S)-3,4-DHGA, via simple oxidation and hydrolysis in a highly stereoselective manner and a higher yield than the previous syntheses. This result strongly supports that our synthetic methodology of stereoselective $OsO_4$-catalyzed dihydroxylation should be useful in stereoselctive synthesis of various bioactive compounds with an amino diol moiety.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.3
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• pp.199-204
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• 2011

To characterize phytonutrients, the seeds of 12 purple Perilla (Perilla frutescens var. crispa) accessions collected from Korea and Japan were used for quantitative analysis of tocopherols, phytosterols, squalene and fatty acids. The average tocopherol, squalene and phytosterols contents were 12.2 mg $100g^{-1}$, 3.99 mg $100g^{-1}$ and 77.20 mg $100g^{-1}$, respectively. Among 4 tocopherol (T) isomers (${\alpha}$-T, ${\beta}$-T, ${\gamma}$-T, and ${\delta}$-T), ${\gamma}$-T was present in the highest quantity (11.03 mg $100g^{-1}$) with the least variation (CV = 13.7%), while ${\beta}$-T was present in lowest quantity (0.25 mg 1$100g^{-1}$). Compared to campesterol (4.36 mg $100g^{-1}$) and stigmasterol (13.32 mg $100g^{-1}$), ${\beta}$-sitosterol exhibited higher quantity (59.51 mg $100g^{-1}$) with 9.5% of variation. The major fatty acids were unsaturated fatty acids such as linolenic (61.5%), linoleic (17.3%), and oleic (9.9%) acids compared to saturated ones: palmitic (7.6%) and stearic (3.7%) acids. When Korean and Japanese accession were compared, almost no difference in content could be observed, while more variation as evaluated by CV (%) could be observed in Japanese accession in most phytonutrients suggesting wider genetic variation of purple Perilla in Japan. Presence of all above-mentioned phytonutrient compounds strongly suggested health beneficial value of purple Perilla seeds.

• Molecular & Cellular Toxicology
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• v.5 no.3
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• pp.230-236
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• 2009

Acrolein, a known toxin in cigarette smoke, is the most abundant electrophilic $\alpha$, $\beta$-unsaturated aldehyde to which humans are exposed in a variety of environmental pollutants, and is also product of lipid peroxidation. Increased unsaturated aldehyde levels and reduced antioxidant status plays a major role in the pathogenesis of various diseases such as diabetes, Alzheimer's and atherosclerosis. The findings reported here show that low concentrations of acrolein induce heme oxygenase-1 (HO-1) expression in RAW 264.7 macrophages. HO-1 induction by acrolein and signal pathways was measured using reverse transcription-polymerase chain reaction, Western blot and immunofluorescence staining analyses. Inhibition of extracellular signal-regulated kinase activity significantly attenuated the induction of HO-1 protein by acrolein, while suppression of Jun N-terminal kinase and p38 activity did not affect induction of HO-1 expression. Moreover, rottlerin, an inhibitor of protein kinase $\delta$, suppressed the upregulation of HO-1 protein production, possibly involving the interaction of NF-E2-related factor 2 (Nrf2), which has a key role as a HO-1 transcription factor. Acrolein elevated the nuclear translocation of Nrf2 in nuclear extraction. The results suggest that RAW 264.7 may protect against acrolein-mediated cellular damage via the upregulation of HO-1, which is an adaptive response to oxidative stress.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.168-174
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• 2023

In commercial production processes of methyl methacrylate, there is a methacryl aldehyde as an intermediate or impurities. The existence of impurities is critical factor because of significant decrease of the conversion rate and selectivity of the entire chemical reaction. This study found that an acid was the main cause of the decrease in reactivity among various impurities because an acid rapidly lowers the activity of a catalyst and promotes a side reaction, the hetero Diels-Alder reaction. Therefore, the pretreatment methods with the removal of acid were comparatively evaluated by the selective hydrogenation reaction of the carbonyl group of the reactants. Based on several experimental conditions, we believe that proposed effective pretreatment improves productivity with appropriate economical process.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.26-32
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• 2001

[ ${\alpha},{\beta}$ ]-Unsaturated carboxamides 12 with trifluromethylated dihydro-1,4-dithiins were synthesized for the purpose of development of new agrochemical fungicide. Chlorination of trifluoromethylated ${\beta}$-ketoester 4 followed by tile reaction with 1,2-ethanedithiol gave intermediate 1,4-dithiane 9. Without purification of 9 substitution of hydroxy by chlorine followed by dehydrochlorination in the presence of triethylamine afforded trifluoromethylated dihydro-1,4-dithiin ethyl ester 7. Activation of the hydroxy of the carboxylic acid 10 obtained from the hydrolysis of 7 and then reacted with various amines gave the corresponding trifluoromethylated dihydro-1,4-dithiin carboxamides. Antifungal screening (in vivo) against typical plant diseases, Rice Blast, Rice Sheath Blight, Cucumber Gray Mold, Tomato Late Blight, Wheat Leaf Rust, and Barley Powdery Mildew of the synthesized compounds was carried out. As a result, most of the compounds shlowed weak antifungal activities and some compounds in which isopropyl group was substituted in meta of the phenyl showed antifungal activity (99%) at 250 ppm against the disease Wheat Leaf Rust.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2618-2626
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• 2010

In this paper poly (4-methyl vinylpyridinium hydroxide)/SBA-15 composite was prepared as a highly efficient heterogeneous basic catalyst by in situ polymerization method for the first time. It was characterized by XRD, FT-IR, BET, TGA, SEM and back titration using NaOH. This catalyst exhibited the excellent catalytic activities for the Knoevenagel condensation of various aldehydes with ethyl cyanoacetate. Over this catalyst, ${\alpha},{\beta}$-unsaturated carbonyl compounds were obtained in the reasonable yield at $95^{\circ}C$ in 10 - 30 min in $H_2O$ as a solvent with a 100% selectivity to the condensation products. Catalyst could be easily recycled after the reaction and it could be reused without the significant loss of activity/selectivity performance. No by-product formation, high yields, short reaction times, mild reaction conditions and operational simplicity with reusability of the catalyst were the salient features of the present synthetic protocol. Presence of $H_2O$ as a solvent was also recognized as a "green method".

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1868-1873
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• 2006

A novel microorganism that could degrade high molecular weight gellan was screened and isolated from soil. On gellan plate, the microorganism grew well and completely liquefied the plate. The gellan-degrading microorganism was isolated by pure culture on glucose and nutrient agar medium afterwards. The 16S rDNA sequence analysis and biochemical tests using an API 50CHB/20E kit revealed that the strain belonged to Bacillus sp. The isolate, named as Bacillus sp. YJ-1, showed optimum gellan-degrading activity in 0.5% gellan medium at pH 7.5 and 37$^{\circ}C$. The activity was measured and evaluated by the thiobarbituric acid and thin-layer chromatography method. Mass spectrometry revealed that the major gellan.. depolymerized product was an unsaturated tetrasaccharide consisting of $\Delta$4,5-glucuronic acid-(1$\rightarrow$4 )-$\beta$-D-glucose-(1$\rightarrow$4)- $\alpha$-L-rhamnose-(1$\rightarrow$3)-$\beta$-D-glucose, which is a dehydrated repeating unit of gellan, thus the enzyme was identified as gellan lyase. When the gellan was present in the medium, the gellan-degrading activity was much higher than that in glucose-grown cells. These results indicate that in the presence of gellan, Bacillus sp. YJ-1 is able to metabolize the gellan by inducing gellan-degrading enzymes that can degrade gellan into small molecular weight oligosaccharides, and then the gellan. depolymerized products are taken up by the cells and utilized by intracellular enzymes.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.26 no.2
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• pp.99-115
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• 2023

Purpose: Exclusive breastfeeding promotes gut microbial compositions associated with lower rates of metabolic and autoimmune diseases. Its cessation is implicated in increased microbiome-metabolome discordance, suggesting a vulnerability to dietary changes. Formula supplementation is common within our low-income, ethnic-minority community. We studied exclusively breastfed (EBF) neonates' early microbiome-metabolome coupling in efforts to build foundational knowledge needed to target this inequality. Methods: Maternal surveys and stool samples from seven EBF neonates at first transitional stool (0-24 hours), discharge (30-48 hours), and at first appointment (days 3-5) were collected. Survey included demographics, feeding method, medications, medical history and tobacco and alcohol use. Stool samples were processed for 16S rRNA gene sequencing and lipid analysis by gas chromatography-mass spectrometry. Alpha and beta diversity analyses and Procrustes randomization for associations were carried out. Results: Firmicutes, Proteobacteria, Bacteroidetes and Actinobacteria were the most abundant taxa. Variation in microbiome composition was greater between individuals than within (p=0.001). Palmitic, oleic, stearic, and linoleic acids were the most abundant lipids. Variation in lipid composition was greater between individuals than within (p=0.040). Multivariate composition of the metabolome, but not microbiome, correlated with time (p=0.030). Total lipids, saturated lipids, and unsaturated lipids concentrations increased over time (p=0.012, p=0.008, p=0.023). Alpha diversity did not correlate with time (p=0.403). Microbiome composition was not associated with each samples' metabolome (p=0.450). Conclusion: Neonate gut microbiomes were unique to each neonate; respective metabolome profiles demonstrated generalizable temporal developments. The overall variability suggests potential interplay between influences including maternal breastmilk composition, amount consumed and living environment.