• Title/Summary/Keyword: $^3H$

Search Result 60,511, Processing Time 0.073 seconds

Synthesis and Characterization of a Di-$\mu$-oxo-bridged Molybdeum(V) Complexes (두 개 산소가교형 몰리브덴(V) 착물의 합성과 그 성질에 관한 연구)

  • Doh, Gil Myung;Kim, Ill Chool;Choi, Bo Yong
    • Journal of the Korean Chemical Society
    • /
    • v.39 no.3
    • /
    • pp.198-203
    • /
    • 1995
  • The Mo(V) $di-\mu-oxo$ type $(Mo_2O_4(H_2O)_2L)$ complexes $(L:\;C_3H_7CH(SCH_2COOH)_2,\;C_6H_5CH(SCH_2COOH)_2,\;CH_3OC_6H_4CH(SCH_2COOH)_2,\;C_5H_{10}C(SCH_2COOH)_2,\;C_3H_7C(CH_3)(SCH_2COOH)_2,\;C_3H_7CH(SCH_2CH_2COOH)_2,\;C_6H_5CH(SCH_2CH_2COOH)_2)$ have been prepared by the reaction of $[Mo_2O_4(H_2O)_6]^{2+}$ with a series of dithiodicarboxy ligands. These complexes are completed by two terminal oxygens arranged trans to one another and each ligand forms a chelate type between two molybdenum. In $Mo_2O_4(H_2O)_2L$, two $H_2O$ coordinated at trans site of terminal oxygens. The prepared complexes have been characterized by elemental analysis, infrared spectra, electronic spectra, and nuclear magnetic resonance spectra. In the potential range -0.00 V to -1.00 V at a scan rate of 20 $mVs^{-1}$, a cathodic peak at -0.50∼-0.58 V (vs. SCE) and an anodic peak at -0.40∼-0.43 V (vs. SCE) have been observed in aquous solution. The ratio of the cathodic to anodic current ($I_{pc}/I_{pa}$) is almost 1, we infer that redox is reversible reaction.

  • PDF

Synthesis and Tautomerism of Pyrido[2,3-b]pyrazines (Pyriodo[2,3-b]pyrazine류의 합성과 토토머화 현상)

  • Kim, Ho-Sik;Choi, Kyung-Ok;Kurasawa, Yoshihisa
    • Journal of the Korean Chemical Society
    • /
    • v.44 no.5
    • /
    • pp.435-440
    • /
    • 2000
  • The reaction of 2-methoxycarlmethylen-l,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one(5) with hydrazine hydrate and ethylenediamine gave 2-hydrazinocarbonylmethylene-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one(6) and 2-aminoethylcarbamethylene-1,2-dihydro-4H-pyrido[2,3-b]pyrazin-3-one(7), res-pectively. The reaction of compound 6 or 7 with substituted benzaldehydes or heteroaryl aldehydes afforded pyrido[2,3-b]pyrazines(8-13). Some pyrin the enamine, methylene imine and enaminol forms in solution. The tau-tomer ratios were determined by the H NMR.

  • PDF

Crystal Structure Analysis of Methyl-3-phenyl-3H-chromeno[4,3-c]isoxazole-3a(4H)-carboxylate

  • Ganapathy, Jagadeesan;Srinivasan, J.;Manickam, Bakthadoss
    • Journal of Integrative Natural Science
    • /
    • v.8 no.3
    • /
    • pp.184-191
    • /
    • 2015
  • The crystal structure of the potential active methyl-3-phenyl-3H-chromeno[4,3-c]isoxazole-3a(4H)-carboxylate ($C_{18}H_{15}NO_4$) has been determined from single crystal X-ray diffraction data. In the title compound crystallizes in the orthorombic space group $P2_12_12_1$ with unit cell dimension $a=9.8320(17){\AA}$, $b=9.9890(18){\AA}$ and $c=15.588(3){\AA}$ [${\alpha}=90^{\circ}$, ${\beta}=90^{\circ}$ and ${\gamma}=90^{\circ}$]. In the structure chromene, isoxazole and carboxylate are almost coplanar each other. All geometrical parameters revelled that chromene ring of pyran ring adopt sofa conformation. The crystal packing is stabilized by intermolecular C-H...O and C-H...N hydrogen bond interaction.

Reactions of Purine Derivatives with Phosphorus Pentnoxide and Triethylamine and Their Antitumor Effects

  • Moharram, H.H.;Osman, A.M.
    • Archives of Pharmacal Research
    • /
    • v.12 no.1
    • /
    • pp.1-4
    • /
    • 1989
  • 6-Arylamino-3,7-dihydro-3,7-dimethy-2-oxo-1H-purine and 2-arylimino-6-arylamino-3,7-dihydro-3,7-dimethyl-1H-purine were obtained in a one-pot reaction when 3,7-dihydro-3,7-dimethyl-1H-purine-3,6-dione, phosphorus pentaoxide, triethylamine hydrochloride and appropriate amine amino are heated at $170^{\circ}$. Some derivatives were tested for their antitumor activity.

  • PDF

Study of molecular motion by 1H NMR relaxation in ferroelectric LiH3(SeO3)2, Li2SO4·H2O, and LiN2H5SO4 single crystals

  • Park, Sung Soo
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.20 no.1
    • /
    • pp.1-6
    • /
    • 2016
  • The proton NMR line widths and spin-lattice relaxation rates, $T_1^{-1}$, of ferroelectric $LiH_3(SeO_3)_2$, $Li_2SO_4{\cdot}H_2O$, and $LiN_2H_5SO_4$ single crystals were measured as a function of temperature. The line width measurements reveal rigid lattice behavior of all the crystals at low temperatures and line narrowing due to molecular motion at higher temperatures. The temperature dependences of the proton $T_1^{-1}$ for these crystals exhibit maxima, which are attributed to the effects of molecular motion by the Bloembergen - Purcell - Pound theory. The activation energies for the molecular motions of $^1H$ in these crystals were obtained. From these analysis, $^1H$ in $LiH_3(SeO_3)_2$ undergoes molecular motion more easily than $^1H$ in $LiN_2H_5SO_4$ and $Li_2SO_4{\cdot}H_2O$ crystals.

Control of a Three-Dimensional Character Animation Based on H-Anim (H-Anim 기반의 3차원 캐릭터 애니메이션 제어)

  • Kim, Young-Shin;Lee, Min-Geun;Lee, Myeong-Won
    • Journal of the Korea Computer Graphics Society
    • /
    • v.13 no.4
    • /
    • pp.1-6
    • /
    • 2007
  • In this paper we describe the method of controlling the animation of 3D characters according to ISO/IEC 19774 (H-Anim) specification, which has been released by Wed3D Consortium and ISO/IEC SC24 WG6. The animation structure of the H-Anim character can be defined and modified in our H-Anim editor program. Our H-Anim animator generates the character's motion automatically according to the input of motion parameters at the character's joints interactively. This paper is focused on the development of a motion generation tool for human-like characters defined by H-Anim structures.

  • PDF

Effects of Acid Treatments on Chlorophyll, Carotenoid and Anthocyanin Contents in Arabidopsis (산성처리가 애기장대의 엽록소, 카로티노이드, 안토시아닌 등의 색소 함량에 미치는 영향)

  • Im, Kyung-Hoan
    • Research in Plant Disease
    • /
    • v.16 no.1
    • /
    • pp.81-85
    • /
    • 2010
  • Arabidopsis seedlings subjected to low pH stress in the range of pH 5.6-4.0 did not show significant retardations in root and shoot growths. Treatment of pH 3.5-2.5 resulted in significant reductions in root and shoot length, especially in roots. Chlorophyll contents in seedlings increased during acid treatment of pH 5.6-4.0, but decreased by stronger acid treatment of pH 4.0 and lower pHs. Total carotenoid contents showed similar trend to chlorophyll contents by increasing during pH 5.6-3.5 treatments and decreasing by pH 3.0-2.5. Anthocyanin contents increased under acid stress of pH 5.6-3.0 and showed great reduction at pH 2.5. The ratios of carotenoids/chlorophylls and anthocyanins/chlorophylls increased by acid stress treatments. That indicates plants try to adjust physiologically to acid stress and protect chlorophylls by increasing carotenoid and anthocyanin contents. However, different responses of chlorophylls and anthocyanins to acid stress indicate both pigments play different roles in protecting plant from acid stress.

The Effects of CIF$_3$and F$_2$on the Flammability Limit of H$_2$ (H$_2$의 연소한계에 미치는 F$_2$와 CIF$_3$의 영향)

  • ;H.Ohtani;Y.Uehara
    • Journal of the Korean Society of Safety
    • /
    • v.9 no.3
    • /
    • pp.53-59
    • /
    • 1994
  • Hydrogen(H$_2$) is used in the semiconductor industries, and some oxidizing gases such as fluoride(F$_2$) and chlorine trifluoride(CIF$_3$) are also used. As F$_2$and CIF$_3$are highly oxidizing gases, it were supposed to react vigorously with H$_2$. In this study, the flammability limit of F$_2$/$H_2$/Ar and CIF$_3$/$H_2$/Ar mixtures were investigated experimentally. As a result, it was found that the diluted F$_2$gas could be spontaneously ignited as compared to CIF$_3$mixture gas while being mixed with the diluted H$_2$gas. However, CIF$_3$diluted gas was not able to ignite spontaneously except for an electric spark. And the combustion characteristics and reaction kinetics were shown at the different diluted gases by the flammability diagram analyses between the F$_2$/$H_2$/Ar and CIF$_3$/$H_2$/Ar.

  • PDF

Isolation and Characterization of 5,6-Dimethoxy-1,2,3,4-tetrahydro-2(1H)-naphthalenone from Catalytic Reductions of the Respective 2-Amino-, and 2-Nitro-3,4-dihydro-5,6-dimethoxy-1(2H)-naphthalenone (2-Amino-와 2-Nitro-3,4-dihydro-5,6-dimethoxy-1(2H)-naphthalenone의 촉매수소화에서 5,6-Dimethoxy-1,2,3,4-tetrahydro-2(1H)-naphthalenone의 분리 및 구조결정)

  • Kim Jack C.
    • Journal of the Korean Chemical Society
    • /
    • v.23 no.2
    • /
    • pp.94-98
    • /
    • 1979
  • From the catalytic reductions of the respective 2-amino-, and 2-nitro-3,4-dihydro-5,6-dimethoxy-1(2H)-naphthalenone, a major reduction product of 2-amino-5,6-dimethoxy-1,2,3,4-tetrahydro-naphthalene was obtained, along with a minute amount of rearranged product, 5,6-dimethoxy-1,2,3,4-tetrahydro-2(1H)-naphthalenone. The unusual formation of 5,6-dimethoxy-1,2,3,4-tetrahydro-2(1H)-naphthalenone was verified on the basis of ir, and nmr spectra, and elemental analysis. A plausible mechanism for the rearrangement is proposed.

  • PDF

The Kinetics and Mechanism of Nucleophilic Addition of Mercaptan to a ${\beta}$-Nitrostyrene in Acidic Media (I) (${\beta}$-Nitrostyrene에 대한 Mercaptan의 親核性 添加反應에 關한 硏究 (I))

  • Park, Ok-Hyun
    • Journal of the Korean Chemical Society
    • /
    • v.12 no.3
    • /
    • pp.106-113
    • /
    • 1968
  • The rate-constants of the nucleophilic addition reaction of n-butylmercaptan to 3,4-methylenedioxy-${\beta}$-nitrostyrene were determined at various acidic pH and a rate equation which can be applied over wide pH range was obtained. From this equation, one may conclude that this reaction is started by addition of mercaptan molecule below pH 3, while above pH 6, the overall rate of addition is almost only depend upon the concentration of nitrostyrene and the mercaptide ion. At pH 3∼6, the complex mechanism of this addition reaction can also be fully explained by the rate equation.

  • PDF