• Transactions on Electrical and Electronic Materials
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• 제13권1호
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• pp.43-46
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• 2012

Organic solar cell devices were fabricated using poly[9-(1-octylnonyl)-9H-carbazole-2.7-diyl]-2.5-thiophenediyl-2.1.3-benzothiadiazole-4.7-diyl-2.5-thiophenediyl] PCDTBT/ [6,6]-phenyl $C_{71}$ butyric acid methyl ester (PC71BM) active layer deposited by spin coating. Moreover, the relationship between solar cell performance and buffer layer thickness was investigated by spin coating speed and AFM imaging of the buffer layer surface. The performance of the organic solar cell with spin-coated active layer was then evaluated, and the power conversion efficiency of the solar cell was determined to be > 5%.

• Journal of Pharmaceutical Investigation
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• 제27권2호
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• pp.125-131
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• 1997

Ethoxycarbonyloxyethyl ester of ceftezole (CFZ-ET) was synthesized as a prodrug by esterification of ceftezole (CFZ) with ethoxycarbonyloxyethyl chloride and was confirmed by spectroscopic analyses. CFZ-ET was more lipophillic than CFZ as assessed by n-octanol and water partition coefficients at various pH. CFZ-ET itself did not show any microbiological activity in vitro, but showed substaintial microbiological activity after oral administration of CFZ-ET, indicating that CFZ-ET is converted to microbiologically active metabolite, probably CFZ, in the body. When CFZ-ET was incubated in blood, liver and intestine homogenates of rabbits, liver homogenate showed the fastest conversion of CFZ-ET. CFZ-ET appears rapidly metabolized in the liver when given orally due to the hydrolysis of the ester to CFZ, the parent drug of CFZ-ET. In vivo metabolism of CFZ-ET to CFZ was confirmed in rabbit by HPLC analysis. CFZ-ET were higher than those in the serum samples taken after oral administration of equivalent amount of CFZ. Oral bioavailability of CFZ-ET was 1.5-fold higher than that of CFZ in rabbits because of enhanced lipophilicity and absorption. Based on these findings, CFZ-ET appears useful as a prodrug of CFZ to improve the oral bioavailability of CFZ.

• Journal of the Korean Chemical Society
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• 제37권1호
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• pp.154-161
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• 1993

Four kinds of new phosphinate derivatives with a pendant monoazacrown ether were synthesized and their biological activities were tested. These biologically active phosphinates were synthesized in relatively good yields (61∼72%) by one step reactions of phenylphosphinate with aldehyde and monoazacrown ether. Toxicity of these compounds was tested by intraperitoneal injection of the compounds to male mouse and revealed $LD_{50}$ value of 65∼90 mg/kg, which showed enhanced toxicity by attachment of a pendant azacrown ether to a simple phenylphosphinate structure. Although the ring size effect of the pendant crown ethers, (monoaza-15-crown-5 and monoazo-18-crown-6), beening negligible, the identity of the ester functional group in the phosphinate structure exerted sizable influence on toxicity. Thus, phosphinate derivative with octyl or propyl ester group showed somewhat higher toxicity than that with ethyl ester group.

• Applied Chemistry for Engineering
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• 제9권5호
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• pp.749-753
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• 1998

Methoxy polyoxyethylene dodecanoates, kinds of nonionic surfactants, could be obtained from addition of ethylene oxide (5, 7, 9, and 12mol) with fatty acid methyl ester utilizing solid catalyst, metal oxide. Because ethylene oxide (EO) couldn't react directly in acid or alkali catalyst with dodecanoic acid methyl ester (DME) that had no active hydrogen, the reaction to add EO was carried out using active solid catalyst. By using IR, HPLC and $^1H$ NMR analysis, structural confirmation of methyl polyoxy ethylene dodecanate showed high yield ranging from 93 to 97%. EO unit mol number of reacted products was 5.2, 7.1, 9.2 and 12.1 mol respectively. Also, EO adduct distrobution of ethoxylated methyl laurate (MPD) had normal distribution curve like polyoxyethylene alkyl ether (AE).

• Natural Product Sciences
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• 제25권1호
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• pp.64-71
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• 2019

The present study was conducted to investigate anti-nociceptive and anti-inflammatory effects of the leaves of Ilex latifolia Thunb (I. latifolia) in in vivo and in vitro. Writhing responses induced by acetic acid and formalin- and thermal stimuli (tail flick and hot plate tests)-induced pain responses for nociception were evaluated in mice. I. latifolia (50 - 200 mg/kg, p.o.) and ibuprofen (100 mg/kg, p.o.), a positive non-steroidal anti-inflammatory drug (NSAID), inhibited the acetic acid-induced writhing response and the second phase response (peripheral inflammatory response) in the formalin test, but did not protect against thermal nociception and the first phase response (central response) in the formalin test. These results show that I. latifolia has a significant anti-nociceptive effect that appears to be peripheral, but not central. Additionally, I. latifolia (50 and $100{\mu}g/mL$) and 3,5-di-caffeoyl quinic acid methyl ester ($5{\mu}M$) isolated from I. latifolia as an active compound significantly inhibited LPS-induced NO production and mRNA expression of the pro-inflammatory mediators, iNOS and COX-2, and the pro-inflammatory cytokines, IL-6 and $IL-1{\beta}$, in RAW 264.7 macrophages. These results suggest that I. latifolia can produce antinociceptive effects peripherally, but not centrally, via anti-inflammatory activity and supports a possible use of I. latifolia to treat pain and inflammation.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1659-1664
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• 2014

A porous metal-organic framework (MOF), MIL-101, was synthesized in the presence of sulfated zirconia (SZ) to produce acidic SZ/MIL-101 composites for the first time. The composites were characterized with XRD, nitrogen adsorption, FT-IR, scanning electron microscope, chemical analysis and so on. The composites (SZ/MIL-101s) were successfully applied in a liquid-phase esterification for a high yield of ester. This catalytic result of SZ/MIL-101, compared with that of pure SZ or MIL-101 (showing a negligible yield of ester), suggests that the SZ in the composite is highly active in the acid catalysis probably because of the well-dispersed active species of SZ. Moreover, the esterification is catalyzed in heterogeneous mode as confirmed by negligible esterification after filtration of the catalyst. Finally, microwaves can be efficiently applied both in the synthesis of the composites and the esterification reaction to accelerate the two processes of synthesis and esterification by about 5 times.

• Proceedings of the Korean Vacuum Society Conference
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.313-313
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• 2010

The performance of polymer photovoltaic cells based on blends of poly(3-hexylyhiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) is strongly influenced by blend composition and thickness. Polymer photovoltaic cells based on bulk-heterojunction have been fabricated with a structure of ITO/poly(3, 4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)-pentacene/poly (3-hexylthiophene) (P3HT):phenyl-C61-butyric acid methyl ester (PCBM)/Al. We have prepared PEDOT:PSS by dissolving pentacene in N-methylpyrrolidine (NMP) and mixing with PEDOT:PSS. Pentacene was added a maximum concentration of approximately 5.5mg to the PEDOT:PSS solution and sonicated for 10 min. Active layer (P3HT:PCBM) (1:1) was strongly influenced by PEDOT:PSS-pentacene. We have investigated the performance of photovoltaic device with different concentration of P3HT:PCBM (1:1) 2.0wt%, 2.2wt%, 2.4wt% and 2.6wt%, respectively. The photocurrent and power conversion efficiency (PCE) showed a maximum between 2.0wt% and 2.2wt% concentration of P3HT:PCBM. This implied that both morphology and electron transport properties of the layer influenced the performance of the present photovoltaic cells. As the concentration of P3HT:PCBM blends as an active layer was increased, the power conversion efficiency was decreased. P3HT:PCBM layer and PEDOT:PSS-pentacene layer were characterized by work function, UV-visible absorption, atomic force microscopy (AFM), X-ray diffraction (XRD) and scanning electron microscope (SEM).

• Applied Biological Chemistry
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• 제46권3호
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• pp.240-245
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• 2003

$({\pm})-2-(4-Chlorophenyl)-2-cyano-2-phenyl-1-hexanol$ (2) and acetate ester (3) were resolved by various lipases. (R) and (S)-systhane were synthesized by the resolved compound 2. The antifungal screening of (R), (S)-systhane and $({\pm})-systhane$ against wheat leaf rust and barley powdery mildew gave activity over 92% in concentration of 2 ppm, but (R)- and (S)-systhane were not more active than $({\pm})-systhane$.

• Korean Journal of Pharmacognosy
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• 제29권1호
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• pp.13-17
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• 1998

The root of Aralia continentalis Kitagawa (Araliaceae) have been used as an analgesic and fever remedy, and for treatment of rheumatism in Chinese medicine, whereas the young leaves are used for ingredient of salad. Antioxidant activity of the young leaves of A. continentails was determined by measuring lipid peroxide produced when a mouse liver homogenate was exposed to the air at $37^{\circ}C$, using 2-thiobarbituric acid (TBA) and by evaluation the radical scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. Chromatographic separation of active fraction led to the isolation of six flavonoids, among which quercetin, hyperoside and kaempferol showed strong antioxidant activities, while 6"-O-acetyl astragalin, astragalin and trifolin were inactive. Adenosine, oleanolic acid 28-O-glucosyl ester and salsoloside C methyl ester isolated from the somewhat active BuOH fraction exhibited no antioxidant activities.

• Proceedings of the Korean Society of Toxicology Conference
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• 한국독성학회 2002년도 국제심포지움
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• pp.88.2-98
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• 2002

A wide arry of naturally occurring substances particularly those present in dietary and medicinal plants, have been reported to possess substantial cancer chemopreventive properties. Certain phytochemicals retain strong antioxidative and anti-inflammatory properties which appear to contribute to their chemopreventive or chemoprotective activities. Inducible cyclooxygenase(COX-2) and nitric oxide synthase (iNOS) are important enzymes that mediate inflammatory processes. There is some evidence that expression of both COX-2 and iNOS is co-regulated by the eukaryotic transcription factor NF-$textsc{k}$B. Increased expression of COX-2 and/or iNOS has been associated with pathophysiology of certain types of human cancers as well as inflammatory diseases. Since inflammation is closely linked to tumor promotion, substances with potent anti-inflammatory activies are anticipated to exert chemopreventive effects on carcinogenesis, particularly in the promotion stage. An example is curcumin, a yellow pigment of turmeric (Curcuma longa L., Zingiberaceae), that strongly occurring diaryl heptanoids structurally related to curcumin have substantial anti-tumor promotional activities in two-stage mouse skin carcinogenesis. Thus, yakuchinone A [1-(4'-hydroxy-3'-methoxyphenyl)-7-phenyl-3heptanone] and yakuchinone B [1-(4'-hydroxy-3'methoxyphenyl)-7-phenylhept-1-en-3-one] present in Alpinia oxyphylla Miquel (Zingiberacease) attenuate phorbol ester-induced inflammation and papilloma formation in female ICR mice. These diarylheptanoids also suppressed phorbol ester-induced activation of epdermal ornithine decarboxylase and its mRNA expression when applied onto shaven backs of mice. Yakuchinone A and B as well as curcumin inhibited phorbol ester-induced expression of COX-2 and iNOS and their mRNA in mouse skin via inactivation of NF-$textsc{k}$B. Capsaicin, a major pungent ingredient of red pepper also attenuated phorbol ester-induced NF-$textsc{k}$B activation. Similar suppression of COX-2 and iNOS and down-regulation of NF-$textsc{k}$B activation for its DNA binding were observed with the ginsenosied Rg3 and the ethanol extract of Artemisia asiatica. We have also found that certain anti-inflammatory phytochemicals exert inhibitory effects on phorbol ester-induced COX-2 expression and NF-$textsc{k}$B activation in immortalized human breast epithelial (MCF-10A) cells in culture. One of the plausible mechanisms undelying inhibition by aforementioned phytochemicals of phorbol ester-induced NF-$textsc{k}$B activation involves interference with degragation of the inhibitory unit, I$textsc{k}$Ba, which blocks subsequent nuclear translocation of the functionally active p65 subunit of NF-$textsc{k}$B. the activation of epidermal NF-$textsc{k}$B by phorbol ester and subsequent induction of COX-2 hence appear to play an important role in intracellular signaling pathwasy leading to tumor promotion and targeted inhibition of NF-$textsc{k}$B may provide a new promising cancer chemopreventive strategy.