• Title/Summary/Keyword: chain rings

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A Series of Transition-metal Coordination Complexes Assembled from 3-Nitrophthalic Acid and Thiabendazole: Synthesis, Structure and Properties

  • Xu, Wen-Jia;Xue, Qi-Jun;Liang, Peng;Zhang, Ling-Yu;Huang, Yan-Feng;Feng, Yu
    • Bulletin of the Korean Chemical Society
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    • v.35 no.1
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    • pp.218-224
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    • 2014
  • In order to explore new coordination frameworks with novel designed 3-nitrophthalic acid and the same N-donor ancillary ligand, a series of novel coordination complexes, namely, $[Cd_2(3-NPA)_2(TBZ)_2(H_2O)_2]{\cdot}2H_2O$(1), $[Zn_2(3-NPA)_2(TBZ)_2]$(2), $[Zn_2O(3-NPA)(TBZ)(H_2O)]_n$(3), $[Co(3-NPA)(TBZ)(H_2O)]_n$(4) (3-$NPAH_2$ = 3-nitrophthalic acid), have been hydrothermally synthesized through the reaction of 3-nitrophthalic acid with divalent transition-metal salts in the presence of N-donor ancillary coligand (TBZ = thiabendazole). As a result of various coordination modes of the versatile 3-$NPAH_2$ and the coligand TBZ, these complexes exhibit structural diversity. X-ray structure analysis reveals that 1 and 2 are 0D molecular rings, while 3 and 4 are one-dimensional (1D) infinite chain polymers. And the weak O-H${\cdots}$O hydrogen bonds and C-H${\cdots}$O nonclassical hydrogen bonds as well as ${\pi}-{\pi}$ stacking also play important roles in affecting the final structure where complexes 1, 3 and 4 have 3D supramolecular architectures, while complex 2 has a 2D supramolecular network. Also, IR spectra, fluorescence properties and thermal decomposition process of complexes 1-4 were investigated.

Potentiometric Study of Transition Metal Ions Complexes of Hexadentate($N_4$, $O_2$) Ligands (질소-산소계 여섯 자리 리간드들의 전이금속이온 착물에 대한 전위차법 연구)

  • Kim, Sun-Deuk;Kim, Jun-Kwang;Lee, Woo-Sik
    • Journal of the Korean Chemical Society
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    • v.44 no.6
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    • pp.518-525
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    • 2000
  • The open-chain hexadentate N$_4$, O$_2$ ligands 1,13-bis(2-hydroxybenzyl)-2,5,9,12-tetraazatridecane-tetrahydrochloride (BSATD${\cdot}$4HCl) and 1,14-bis (2-hydroxybenzyl)-2,6,9,12-tetraazatetradecane-tetrahydrochloride (BSATED${\cdot}$ 4HCl) have been synthesized as their tetrahydrochloride salt and characterized by EA, IR, NMR and Mass. Their proton dissociation constants(log$K^{n}_{H}$) and stability constants(log$K_{ML}$) for Cu(II), Ni(II), Co(II), and Zn(II) ions were determined in aqueous solution by potentiometry and compared with those of analogous N$_4$, O$_2$ ligands contain ethylenic spacers or propylenic spacers, which make six-membered chelate rings between the aliphatic nitrogen atoms. Synthesis and characterization of [Cu(BSATD)]ClO$_4$ and [Cu(BSATED)](ClO$_4$)$_2$ complexes are described.

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Synthesis and Photovoltaic Properties of Polymers Based on Cyclopentadithiophene and Benzimidazole Units

  • Song, Su-Hee;Park, Sei-Jung;Kwon, Soon-Cheol;Shim, Joo-Young;Jin, Young-Eup;Park, Sung-Heum;Kim, Il;Lee, Kwang-Hee;Suh, Hong-Suk
    • Bulletin of the Korean Chemical Society
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    • v.33 no.6
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    • pp.1861-1866
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    • 2012
  • The new semiconducting copolymers with 4,4-dialkyl-$4H$-cyclopenta[2,1-$b$:3,4-$b^{\prime}$]dithiophene and 2,2-dimethyl-$2H$-benzimidazole units were synthesized. The fused aromatic rings, such as cyclopentadithiophene (CPDT) unit, can make the polymer backbone more rigid and coplanar, which induces long conjugation length, narrow band gap, and strong intermolecular ${\pi}-{\pi}$ interaction. The stacking ability was controlled through attaching of linear or branched alkyl side chains. The spectra of PEHCPDTMBI and PHCPDTMBI in the solid films show absorption bands with maximum peaks at 401, 759 and 407, 768 nm, and the absorption onsets at 925 and 954 nm, corresponding to band gaps of 1.34 and 1.30 eV, respectively. The devices comprising PHCPDTMBI with $TiO_X$ showed a $V_{OC}$ of 0.39 V, a $J_{SC}$ of 1.14 $mA/cm^2$, and a $FF$ of 0.34, giving a power conversion efficiency of 0.15%. The PHCPDTMBI with linear alkyl chain on CPDT shows good solubility in organic solvent with higher PCE value than that of PEHCPDTMBI.

Angiogenesis Inhibitor Derived from Angiostatin Active Sites

  • Park, Kyoung-Soo;Lim, Dong-Yeol;Park, Sang-Don;Kim, Min-Young;Kim, Yang-Mee
    • Bulletin of the Korean Chemical Society
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    • v.25 no.9
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    • pp.1331-1335
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    • 2004
  • Angiogenesis is essential for the growth and persistence of solid tumors. Their metastases, anti-angiogenesis could lead to the suppression of tumor growth. One of the main strategies of cancer treatment is developing molecules of anti-angiogenic activity. In this study, two angiogenic inhibitors, Ang3 (KLFDF) and Ang4 (XLFDF) derived from KLYDY, which is the sequence of angiostatin active sites kringle 5, were designed and synthesized. Previously we reported the activities and structures of two inhibitors, Ang1 (KLYDY) and Ang2 (KLWDF). In order to investigate the effect of Phe substitution, Ang3 was designed with a sequence of KLFDF. In order to reduce conformational flexibility of side chain in Lys, Ang4 was designed with a sequence of XLFDF, where X has amino substituted phenyl ring. Solution structures of those inhibitors were investigated using NMR spectroscopy and their activities as angiogenesis inhibitors were studied. Ang1 and Ang2 show angiogenic activities, while Ang3 and Ang4 have no activities and have extended structures compared to Ang1 and Ang2. Therefore, Phe rings do not have effective hydrophobic interactions with other aromatic residues in Ang3 and Ang4. The representative structure of Ang2 has a stable intramolecular hydrogen bond. Therefore, intramolecular hydrogen bonding might be more important in stabilizing the structure than the hydrophobic interactions in these inhibitors. More rigid structure, which can be expected to have higher activities and better match with the receptor bound conformations, can be obtained with a constrained cyclic structure. Further peptidomimetic approaches should be tried to develop angiogenesis inhibitors.

IL-8/CXCL8 Upregulates 12-Lipoxygenase Expression in Vascular Smooth Muscle Cells from Spontaneously Hypertensive Rats

  • Kim, Jung-Hae;Kang, Young-Jin;Kim, Hee-Sun
    • IMMUNE NETWORK
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    • v.9 no.3
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    • pp.106-113
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    • 2009
  • Background: We previously demonstrated remarkable differences in the expression of IL-8/CXCL8 in aortic tissues and vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) compared to VSMC from normotensive Wistar-Kyoto rats (WKY). In the present study, we investigated the direct effect of IL-8/CXCL8 on expression of 12-lipoxygenase (LO), a hypertensive modulator, in SHR VSMC. Methods: Cultured aortic VSMC from SHR and WKY were used. Expression of 12-LO mRNA was determined by real-time polymerase chain reaction. Phosphorlyation of ERK1/2 and production of 12-LO and angiotensin II subtype 1 ($AT_1$) receptor were assessed by Western blots. IL-8/CXCL8-stimulated DNA synthesis was determined by measuring incorporation of [$^3H$]-thymidine. And effect of IL-8/CXCL8 on vascular tone was determined by phenylephrine-induced contraction of thoracic aortic rings. Results: Treatment with IL-8/CXCL8 greatly increased 12-LO mRNA expression and protein production compared to treatment with angiotensin II. IL-8/CXCL8 also increased the expression of the $AT_1$ receptor. The increase in 12-LO induced by IL-8/CXCL8 was inhibited by treatment with an $AT_1$ receptor antagonist. The induction of 12-LO mRNA production and the proliferation of SHR VSMC by IL-8/CXCL8 was mediated by the ERK pathway. The proliferation of SHR VSMC and the vascular contraction in the thoracic aortic ring, both of which were induced by IL-8/CXCL8, were inhibited by baicalein, a 12-LO inhibitor. Conclusion: These results suggest that the potential role of IL-8/CXCL8 in hypertensive processes is likely mediated through the 12-LO pathway.

Analyses of intermediate products during degradation of pyrene in soil by hemoglobin-catalyzed reaction

  • Keum, Haein;Kang, Guyoung
    • Journal of Applied Biological Chemistry
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    • v.61 no.4
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    • pp.335-340
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    • 2018
  • Hemoglobin (Hb) is a member of heme-protein that can perform catalytic non-specific chain reaction in the presence of hydrogen peroxide ($H_2O_2$). Catalytic ability of Hb to degrade pyrene was demonstrated using soil contaminated with $^{14}C$ pyrene and 10 mg pyrene /kg soil. The composition of soil was similar to previously used soil except that it had lower organic carbon content. Bench scale laboratory tests were conducted in the presence of buffer only, $H_2O_2$ only, or Hb with $H_2O_2$ for 24 h. After 24 h reaction, 0.1 and 1.3% of $^{14}C$ pyrene in contaminated soil were mineralized with $H_2O_2$ only or Hb plus $H_2O_2$. No mineralization to $^{14}CO_2$ was detected with buffer only. Approximately 12.2% of pyrene was degraded in the presence of $H_2O_2$ only while 44.0% of pyrene was degraded in the presence of Hb plus $H_2O_2$ during 24 h of catalytic reaction. When degradation intermediate products were examined, two chemicals were observed in the presence of $H_2O_2$ only while 25 chemicals were found in the presence of Hb plus $H_2O_2$. While most degradation products were simple hydrocarbons, four of the 27 chemicals had aromatic rings. However, none of these four chemicals was structurally related to pyrene. These results suggest that Hb catalytic system could be used to treat pyrene-contaminated soil as an efficient and speedy remediation technology. In addition, intermediate products generated by this system are not greatly affected by composition change in soil organic matter content.

Two Polymorphs of Structures of $\alpha,\alpha$-Trehalose Octaacetate Monohydrate

  • Park, Young-Ja;Shin, Jung-Mi
    • Bulletin of the Korean Chemical Society
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    • v.14 no.2
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    • pp.200-206
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    • 1993
  • Structures of two polymorphs of ${\alpha},{\alpha}$-trehalose octaacetate monohydrate, $C_{28}H_{38}O_{19}\;{\cdot}\;H_2O$, have been studied by X-ray diffraction method. ${\alpha},{\alpha}$-trehalose (${\alpha}$-D-glucopyranosyl ${\alpha}$-D-glucopyranoside) is a nonreducing disaccharide. The polymorph I belongs to the monoclinic $P2_1$, and has unit cell parameters of a=10.725(l), b=15.110(4), c=11.199(5) ${\AA}$, ${\beta}=108.16(2)^{\circ}$ and Z=2. The polymorph II is orthorhombic $P2_12_12_1$, with a=13.684(4), b=15.802(4), c=17.990(9) ${\AA}$ and Z=4. The final R and R$_w$ values for monoclinic polymorph I are 0.043 and 0.048 and for orthorhombic polymorph II are 0.116 and 0.118, respectively. Those R values of polymorph II are high because the large thermal motions of acetyl groups and the poor quality of the crystal. The molecular conformations in the two polymorphs are similar. Both D-glucopyranosyl rings have chair $^4C_1$ conformations and atoms of glycosidic chain ${\alpha}(1{\rightarrow}1)$ linkage are coplanar. The primary acetate groups of the pyranose residues assume both gauche-trans conformations. The molecules of two polymorphs have pseudo-C$_2$ symmetry at glycosidic O(1) atom. The bond lengths and angles are normal compared with those in other acetylated sugar compounds. The molecules in the monoclinic crystal are held by the hydrogen bonds with the water molecules and by van der Waals forces.

THE FINITE DIMENSIONAL PRIME RINGS

  • Koh, Kwangil
    • Bulletin of the Korean Mathematical Society
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    • v.20 no.1
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    • pp.45-49
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    • 1983
  • If R is ring and M is a right (or left) R-module, then M is called a faithful R-module if, for some a in R, x.a=0 for all x.mem.M then a=0. In [4], R.E. Johnson defines that M is a prime module if every non-zero submodule of M is faithful. Let us define that M is of prime type provided that M is faithful if and only if every non-zero submodule is faithful. We call a right (left) ideal I of R is of prime type if R/I is of prime type as a R-module. This is equivalent to the condition that if xRy.subeq.I then either x.mem.I ro y.mem.I (see [5:3:1]). It is easy to see that in case R is a commutative ring then a right or left ideal of a prime type is just a prime ideal. We have defined in [5], that a chain of right ideals of prime type in a ring R is a finite strictly increasing sequence I$_{0}$.contnd.I$_{1}$.contnd....contnd.I$_{n}$; the length of the chain is n. By the right dimension of a ring R, which is denoted by dim, R, we mean the supremum of the length of all chains of right ideals of prime type in R. It is an integer .geq.0 or .inf.. The left dimension of R, which is denoted by dim$_{l}$ R is similarly defined. It was shown in [5], that dim$_{r}$R=0 if and only if dim$_{l}$ R=0 if and only if R modulo the prime radical is a strongly regular ring. By "a strongly regular ring", we mean that for every a in R there is x in R such that axa=a=a$^{2}$x. It was also shown that R is a simple ring if and only if every right ideal is of prime type if and only if every left ideal is of prime type. In case, R is a (right or left) primitive ring then dim$_{r}$R=n if and only if dim$_{l}$ R=n if and only if R.iden.D$_{n+1}$ , n+1 by n+1 matrix ring on a division ring D. in this paper, we establish the following results: (1) If R is prime ring and dim$_{r}$R=n then either R is a righe Ore domain such that every non-zero right ideal of a prime type contains a non-zero minimal prime ideal or the classical ring of ritght quotients is isomorphic to m*m matrix ring over a division ring where m.leq.n+1. (b) If R is prime ring and dim$_{r}$R=n then dim$_{l}$ R=n if dim$_{l}$ R=n if dim$_{l}$ R<.inf. (c) Let R be a principal right and left ideal domain. If dim$_{r}$R=1 then R is an unique factorization domain.TEX>R=1 then R is an unique factorization domain.

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"A Study on Hebrews Clothing in the Old Testament" - Especially on Hair Styles, Headgears, Footwear and Personal Ornaments - (구약성서(舊約聖書)에 나타난 히브리인의 복식(服飾) - 두식(頭飾), 신발 및 장신구(裝身具) 중심(中心)으로 -)

  • Park, Chan-Boo
    • Journal of the Korean Society of Costume
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    • v.10
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    • pp.63-80
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    • 1986
  • The Old Testament cotains mention of the history of creation and clothing in ancient Hebrew. This study dealt with Hebrew dress customs especially aimed at the manners of their hair styles, headgears, footwear and personal ornaments. References are Korean Revised Version, English King James Version and Revised Standard Version. There is little mention of hair styles and headgears in the Old Testament. Some sort of turban was worn by priests, and soldiers protected themselves with helmets, but most Israelitish men went bareheaded except on special occasions and often wear simple headbands. It was more common for women to use headwear of some type-turbans, scarves, and veils concealing the face. The veil was the distinctive female wearing apparel. All females, with the exception of maidservants and women in a low condition of life, wore a veil. It was the custom for women to wear a veil entirely covering their head in the public. Through most of the Old Testament periods long and thick hair was admired on men and women alike. The Hebrews were proud to have thick and abundant long hair, and they gave much attention to the care of their hair. The caring of hair was deeply related to their rituals. Nazirites never took a razor to their hair during his vow-days, but instead let it grow long, as an offering to God. Men would not cut their beards, but allow them to grow long. The Israelites' standard footwear was a pair of simple leather sandals. This was one of the items of clothing not highly prized. In a colloquial saying of the time, a pair of shoes signified something of small value, and to be barefoot except in times of mourning or on holy place, was a sign either of extreme poverty or humiliation, as in the case of war prisoners. Because precious stones were not mined in the Palestine-Syria region, Hebrews imported them from foreign country. They were consumer-to a large degree limited by their very modest standard of living-but not producers. Hebrews liked the precious stones and were motivated to acquire and wear jewels. Besides their use for adornment and as gifts, the precious or semiprecious stones were regarded by Jews of property. The Hebrews were not innovators in the field of decorative arts. The prohibition of the Law against making any "graven image" precluded the development of painting, sculpture, and other forms of representational art. Jewish men did not indulge in extravagances of dress, and there was little ornamentation among them. Men wore a signet ring on their right hand or sometimes suspended by a cord or chain around the neck. The necklaces, when worn by a male, also bore any symbol of his authority. Bracelets were extremely popular with both men and women, men usually preferring to wear them on their upper arms. The girdle was a very useful part of a man's clothing. It was used as a waist belt, or used to fasten a man's sword to his body, or served as a pouch in which to keep money and other things. Men often carried a cane or staff, which would be ornamented at the top. Among the women there was more apt to be ornamentation than among the men. Hebrew women liked to deck themselves with jewels, and ornamentation of the bride were specially luxurious and numerous. They wore rings on their fingers or On toes, ankle rings, earrings, nosering, necklace, bracelets. Their shapes were of cresent, waterdrops, scarab, insect, animal or plant. Sometimes those were used as amulets. They were made of ceramics, gold, silver, bronze, iron, and various precious stones which were mostly imported from Egypt and Sinai peninsular. Hebrews were given many religious regulations by Moses Law on their hair, headgears, sandals and ornamentation. Their clothing were deeply related with their customs especially with their religions and rituals. Hebrew religion was of monotheism and of revealed religion. Their religious leaders, the prophets who was inspired by God might need such many religious regulations to lead the idol oriented people to God through them.

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Effect of Hydroxocobalamin on Contractile Responses to Phenylephrine during Administration of Inhalational Anesthetics in Lipopolysaccharide-Treated Rat Aortae (흡입마취제 투여시 내독소혈증흰쥐 대동맥 수축반응에 미치는 Hydroxocobalamin의 효과)

  • Kim, In-Kyeom;Yang, Eun-Kyoung
    • The Korean Journal of Pharmacology
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    • v.32 no.3
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    • pp.381-388
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    • 1996
  • The hemodynamic changes in septic patients produced by inhalational anesthetics are sufficient to threaten the anesthesiologists. The effect of hydroxocobalamin, a vitamin $B_{12a}$, on contractile responses to phenylephrine during administration of inhalational anesthetics were evaluated in aortic ring preparations obtained from LPS-treated rats. The sepsis was developed by intraperitoneal injection of LPS (1.5 mg/kg for l8h) and confirmed by iNOS expression using RT-PCR. Statistical significances (P<0.05) were analyzed by Student's t-test or paired t-test according to data characteristics. The blood pressure, but not heart rate, was decreased in LPS-treated rats as compared to control rats. The contractile response to phenylephrine were dose-dependently increased from the doses of $10^{-8}\;M$ to that of $10^{-5}$ and were attenuated in LPS-treated rings. Both halothane and enflurane, at the doses of 1 MAC, decreased the contractile responses to phenylephrine while isoflurane did not significantly affect the contractile responses. Hydroxocobalamin ($10^{-5}$ M) significantly potentiated the contractile responses in the LPS-treated aortic ring preparations during administration of each inhalational anesthetic or not. From these results, it is suggested that hydroxocobalamin may improve the hemodynamics of septic patients during inhalational anesthesia. Abbreviations: LPS, lipopolysaccharide; RT-PCR, reverse transcription-polymerase chain reaction; MAC, minimum alveolar concentration; iNOS, inducible nitric oxide synthase; GAPDH, glyceraldehyde 3-phosphate dehydrogenase

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