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2-(5,6-디메톡시-1-인데닐)에틸 아민의 합성 (Synthesis of 2-(5,6-dimethoxy-l-indenyl)ethyl amine)

  • 정원영;마은숙
    • 약학회지
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    • 제47권1호
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    • pp.1-4
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    • 2003
  • In order to search the new serotonin bioisoster, 2-(5,6-dimethoxy-l-indenyl)ethyl amine(1) was synthesized. 3,4-Dimethoxybenzaldehyde, as starting material, was condensed with malonic acid in the presence of pyridine and piperidine to form 3,4-dimethoxycinnamic acid(2). Compound 2 was performed catalytic hydrogenation with 10% Pd-C to give propanoic acid derivative 3, which was cyclized by Friedel-Crafts acylation to afford 5,6-dimethoxyindan-l-one(4). Compound 4 was reduced with NaBH$_4$ in ethanol to obtain l-indanol 5, and it was dehydrated to give 5,6-dimethoxy-l-indene(6). This compound was lithiated with 2.5M n-butyllithium and reacted with 1,2-dibromoethane to give 2-(5,6-dimethoxy-l-indenyl)ethyl bromide(7), and which was treated with anhydrous ammonia to synthesize compound 1.

Synthesis and Characterization of New Mono-N-functionalized Tetraaza Macrocyclic Nickel(II) and Copper(II) Complexes

  • Kim, Hyun-Ja;Kang, Shin-Geol
    • Bulletin of the Korean Chemical Society
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    • 제32권8호
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    • pp.2565-2570
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    • 2011
  • The reaction of bromoacetonitrile with 3,14-dimethyl-2,6,13,17-tetraazatetracyclo[$16.4.1^{2.6}.0^{1.18}.0^{7.12}$]tricosane ($L^{10}$) containing a N-$CH_2$-N linkage produces 17-cyanomethyl-3,14-dimethyl-2,6,13,17-tetraazatetracyclo-[$16.4.1^{2.6}.0^{1.18}.0^{7.12}$]tricosane ($L^{11}$). The mono-N-functionalized macrocyclic complexes $[ML^2]^{2+}$ (M = Ni(II) or Cu(II); $L^2$ = 2-cyanomethyl-5,16-dimethyl-2,6,13,17-tetraazatricyclo[$16.4.0.0^{7.12}$]docosane) can be prepared by the reaction of $L^{11}$ with nickel(II) or copper(II) ion in acetonitrile. The N-$CH_2CN$ group attached to $[ML^2]^{2+}$ readily reacts with water or methanol to yield the corresponding complexes of $HL^3$ bearing one N-$CH_2CONH_2$ pendant arm or $L^4$ bearing one $N-CH_2C(=NH)OCH_3$ group. The $N-CH_2CONH_2$ or $N-CH_2C(=NH)OCH_3$ group of each complex is coordinated to the central metal ion. Both $[NiL^4(H_2O)]^{2+}$ and $[CuL^4]^{2+}$ are quite stable in acidic aqueous solutions, but undergo hydrolysis to yield $[Ni(HL^3)(H_2O)]^{2+}$ or $[Cu(HL^3)]^{2+}$ in basic aqueous solutions. In contrast to $[Cu(HL^3)]^{2+}$, $[Ni(HL^3) (H_2O)]^{2+}$ is readily deprotonated to form $[NiL^3 (H_2O)]^+$ ($L^3$ = a deprotonated form of $HL^3$) in basic aqueous solutions.

O2O(Online-to-Offline) 상거래의 성공요인 (Success Factors of O2O(Online-to-Offline) Commerce)

  • 김재경;장유리;정혜진;문윤지
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2015년도 추계학술대회
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    • pp.374-377
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    • 2015
  • O2O(Online-to-offline) 서비스는 온라인에서의 제품 및 서비스 정보검색과 결제, 그리고 오프라인에서의 제품수령이 혼합된 새로운 상거래 방식의 한 형태이다. O2O 상거래는 기존 전자상거래의 장점과 오프라인 상거래의 장점을 결합하고, 각 상거래 유통방식의 한계점을 보완하지만, O2O 기술의 발전속도에 비해 수익모델이 아직까지는 부족한 것이 현실이다. 따라서 소비자 측면에서 O2O 상거래의 성공요인을 탐색하기 위해 본 연구는 O2O 상거래 방식에 포함된 기존 B2C 전자상거래, 모바일 상거래, 그리고 오프라인 상거래의 서비스품질모델(service quality model)을 중심으로 O2O에 적용될 공통 요인을 도출하였다. 나아가 도출된 O2O 성공 서비스 품질요인을 기반으로 질적연구 결과를 반영하여 새로운 O2O 서비스 성공요인이 추가적으로 결합된 O2O 성공요인 모형을 제안한다.

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Refractive-index Prediction for High-refractive-index Optical Glasses Based on the B2O3-La2O3-Ta2O5-SiO2 System Using Machine Learning

  • Seok Jin Hong;Jung Hee Lee;Devarajulu Gelija;Woon Jin Chung
    • Current Optics and Photonics
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    • 제8권3호
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    • pp.230-238
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    • 2024
  • The refractive index is a key material-design parameter, especially for high-refractive-index glasses, which are used for precision optics and devices. Increased demand for high-precision optical lenses produced by the glass-mold-press (GMP) process has spurred extensive studies of proper glass materials. B2O3, SiO2, and multiple heavy-metal oxides such as Ta2O5, Nb2O5, La2O3, and Gd2O3 mostly compose the high-refractive-index glasses for GMP. However, due to many oxides including up to 10 components, it is hard to predict the refractivity solely from the composition of the glass. In this study, the refractive index of optical glasses based on the B2O3-La2O3-Ta2O5-SiO2 system is predicted using machine learning (ML) and compared to experimental data. A dataset comprising up to 271 glasses with 10 components is collected and used for training. Various ML algorithms (linear-regression, Bayesian-ridge-regression, nearest-neighbor, and random-forest models) are employed to train the data. Along with composition, the polarizability and density of the glasses are also considered independent parameters to predict the refractive index. After obtaining the best-fitting model by R2 value, the trained model is examined alongside the experimentally obtained refractive indices of B2O3-La2O3-Ta2O5-SiO2 quaternary glasses.

1,4-Dicyanobutene Bridged Binuclear Iridium (I, III) Complexes and Their Catalytic Activities

  • Park, Hwa-Kun;Chin, Chong-Shik
    • Bulletin of the Korean Chemical Society
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    • 제8권3호
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    • pp.185-189
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    • 1987
  • Reactions of $Ir(ClO)_4(CO)(PPh_3)_2$ with dicyano olefins, cis-NCCH = CH$CH_2$$CH_2$CN (cDC1B), trans-NCCH = CH$CH_2$$CH_2$CN (tDC1B), trans-NC$CH_2$CH = CH$CH_2$CN (tDC2B), and NC$CH_2$$CH_2$$CH_2$$CH_2$CN (DCB) produce binuclear dicationic iridium (I) complexes, $[(CO)(PPh_3)_2Ir-NC-A-CN-Ir(PPh_3)_2(CO)](ClO_4)_2$ (NC-A-CN = cDC1B (1a), tDC1B (1b), tDC2B (1c), DCB (1d)). Complexes 1a-1d react with hydrogen to give binuclear dicationic tetrahydrido iridium (Ⅲ ) complexes, $[(CO)(PPh_3)_2(H)_2Ir-NC-A-CN-Ir(H)_2(PPh_3)_2(CO)](ClO_4)_2$ (NC-A-CN = cDC1B (2a), tDC1B (2b), tDC2B (2c), DCB (2d)). Complexes 2a and 2b catalyze the hydrogenation of cDC1B and tDC1B, respectively to give DCB, while the complex 2c is catalytically active for the isomerization of tDC2B to give cDC1B and tDC1B and the hydrogenation of tDC2B to give DCB at $100^{\circ}C$.

Upregulation of smpd3 via BMP2 stimulation and Runx2

  • Chae, Young-Mi;Heo, Sun-Hee;Kim, Jae-Young;Lee, Jae-Mok;Ryoo, Hyun-Mo;Cho, Je-Yoel
    • BMB Reports
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    • 제42권2호
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    • pp.86-90
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    • 2009
  • Deletion of smpd3 induces osteogenesis and dentinogenesis imperfecta in mice. smpd3 is highly elevated in the parietal bones of developing mouse calvaria, but not in sutural mesenchymes. Here, we examine the mechanism of smpd3 regulation, which involves BMP2 stimulation of Runx2. smpd3 mRNA expression increased in response to BMP2 treatment and Runx2 transfection in C2C12 cells. The Runx2-responsive element (RRE) encoded within the -562 to -557 region is important for activation of the smpd3 promoter by Runx2. Electrophoretic mobility shift assays revealed that Runx2 binds strongly to the -355 to -350 RRE and less strongly to the -562 to -557 site. Thus, the smpd3 promoter is activated by BMP2 and is directly regulated by the Runx2 transcription factor. This novel description of smpd3 regulation will aid further studies of bone development and osteogenesis.

SERO-EPIDEMIOLOGICAL STUDY OF BRUCELLOSIS AMONG GOATS AND SHEEP AT PESHAWAR DISTRICT

  • Ghani, M.;Siraj, M.;Zeb, A.;Naeem, M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제8권5호
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    • pp.489-494
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    • 1995
  • Sero-epidemiological study was carried out to observe the prevalence of brucellosis in 500 slaughtered as well as in 500 healthy animals in Peshawar district of N.W.F.P. All serum samples were subjected to four serological tests i.e. Standard Plate Test (SPT), Standard Tube Test (STT), Rivanol Test (RV) and 2, Mercapto-Ethanol Test (2, ME). The incidence of disease in 500 healthy animals tested by standard plate test, standard tube test, rivanol test and 2, Mercapto-ethanol test, was 2.8%, 1.8%, 1.6% and 1.2% respectively. While the incidence of brucellosis in 500 slaughter animals from Peshawar abattoir was 3.0%, 2.2%, 2.00% and 1.2% by standard plate test, standard tube test, rivanol test and 2, Mercapto-ethanol test The disease prevalence was higher in slaughtered animals as compared to healthy animals. The disease was more common in goats than sheep, also more prevalence in aged female than younger stocks. The efficacy of SPT was found more effective as compared to STT, RV, and 2, ME tests both in slaughtered as well as apparently healthy animals at Peshawar district. Standard Plate test detected 2.9%, Standard Tube test 2.0%, Rivanol test 1.8% and 2, Mercapto-ethanol test detected 1.2% positive cases in slaughtered as well as in healthy animals. So the Standard Plate Test was found to be more reliable, sensitive, and easy to performed.

(${\pm}$)-cis-8-Amino-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno [1,2-b][1,4]oxazine의 합성 (Synthesis of (${\pm}$)-cis-8-amino-l-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno [1,2-b][1,4]oxazine)

  • 마은숙
    • 약학회지
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    • 제52권6호
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    • pp.488-493
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    • 2008
  • 2-Aminothiazole ring as a bioisoster of catechol in dopamine has provided with good oral availability and lipophilic property. 2-Aminoindan, is a rigid form of dopamine, was evaluated as a dopamine D3 agonist with low neurotoxicity. Dopamine D3 agonist was evaluated as selective for the treatment of Parkinson's disease. In order to develop a novel dopamine D3 agonist, we tried to synthesize the aminothiazoloindenoxazine derivative that is a hybrid structure of aminoindenoxazine and thiazole ring. cis-2-Amino-1-indanol (2) was synthesized from 1,2-indandione-2-oxime by catalytic hydrogenation and it was treated with chloroacetyl chloride and NaH in benzene solution to give (${\pm}$)-cis-4,4a,5,9b-tetrahydroindeno[1,2-b][1,4]oxazin-3(2H)-one (6). Nitration of 6 by the mixed acid gave 8-nitro compound (7) and the carbonyl group of 7 was reduced with $LiAlH_4$ to afford compound (8). 8 was reduced to form (${\pm}$)-cis-8-amino-2,3,4,4a,5,9b-hexahydroindeno[1,2-b][1,4]oxazine (9) and finally it was cyclized with KSCN in glacial acetic acid to yield (${\pm}$)-cis-8-amino-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno[1,2-b][1,4]oxazine (10).

Cadmium-Induced Phytotoxicity in Tomato Seedlings Due to the Accumulation of H2O2 That Results from the Reduced Activities of H2O2 Detoxifying Enzymes

  • Cho, Un-Haing
    • The Korean Journal of Ecology
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    • 제27권2호
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    • pp.107-114
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    • 2004
  • Tomato (Lycopersicon esculentum) seedlings exposed to various concentrations of $CdC1_2$ (0∼100 $\mu$M) in the nutrient solution for up to 9 days were analyzed with the seedling growth, $H_2O_2$ production, glutathione levels and activity changes of enzymes related to $H_2O_2$ removal. The growth of seedlings was inhibited with over 50 $\mu$M Cd, whereas the levels of $H_2O_2$ and glutathione were enhanced with Cd exposure level and time. Meanwhile, Cd exposure increased the activities of catalase (CAT) and glutathione reductase (GR) but decreased the activities of dehydroascorbate acid reductase (DHAR) and ascorbate peroxidase (APX) in both leaves and roots. These results suggest that the altered activities of antioxidant enzymes particularly involved in the $H_2O_2$ removal and the subsequent $H_2O$$_2$ accumulation could induce the Cd-induced phytotoxicity.

La2O3가 첨가된 Pd/TiO2 촉매의 개발 및 H2 상온산화 반응에서의 성능 향상 연구 (Development of Pd/TiO2 Catalysts with La2O3 Addition and Study on the Performance Improvement of H2 Oxidation at Room Temperature)

  • 이동윤;김성철;이상문;김성수
    • 공업화학
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    • 제31권6호
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    • pp.674-678
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    • 2020
  • 본 연구에서는 상온 조건에서 추가적인 에너지원 없이 H2 산화가 가능한 Pd/TiO2 촉매를 제조하였고, 지지체인 TiO2의 비표면적은 Pd/TiO2 촉매의 H2 산화 반응 성능과 비례하지는 않은 것을 확인하였다. 또한 촉매의 물성 변화에 의한 성능 영향 평가를 위하여 La2O3를 Pd/TiO2 촉매에 첨가하였다. La2O3를 TiO2에 함량별로 첨가하여 Pd/La2O3-TiO2를 제조하였고, CO chemisorption 분석을 진행하였다. Pd/TiO2(G) 촉매의 전환율(14% at 0.5% H2)과 비교하여 Pd/La2O3-TiO2 촉매가 74% 전환율로 5배 이상의 성능 증진이 나타났다. Pd/La2O3-TiO2 촉매는 활성금속인 Pd의 metal dispersion이 클수록 H2 산화반응에 유리한 것으로 분석되었다. 하지만 첨가되는 La2O3가 10%를 초과하게 되면 촉매 성능이 다시 감소하는 것을 알 수 있었다. 마지막으로 Pd/La2O3-TiO2 촉매의 물성이 지배적인 영향을 미치는 것은 주입되는 H2가 0.3~0.5% 농도 조건까지이며, 1% 이상의 H2 농도부터는 물질전달이 촉매 반응속도를 지배하는 것으로 판단된다.