• Title/Summary/Keyword: chemical binding

Search Result 1,354, Processing Time 0.026 seconds

2-Heteroaryl Benzimidazole Derivatives as Melanin Concentrating Hormone Receptor 1 (MCH-R1) Antagonists

  • Lim, Chae Jo;Kim, Jeong Young;Lee, Byung Ho;Oh, Kwang-Seok;Yi, Kyu Yang
    • Bulletin of the Korean Chemical Society
    • /
    • v.34 no.8
    • /
    • pp.2305-2310
    • /
    • 2013
  • A novel series of 2-heteroaryl substituted benzimidazole derivatives, containing the piperidinylphenyl acetamide group at the 1-position, were synthesized and evaluated as MCH-R1 antagonists. Extensive SAR investigation probing the effects of C-2 heteroaryl group led to the identification of 2-[2-(pyridin-3-yl)ethyl] analog 3o, which exhibits highly potent MCH-R1 binding activity with an $IC_{50}$ value of 1 nM. This substance 3o also has low hERG binding activity, good metabolic stability, and favorable pharmacokinetic properties.

Direct Stacking of Non-metallic Planar Porphyrin to DNA

  • Lee, Min-Ju;Jin, Biao;Lee, Hyun-Mee;Jung, Maeng-Joon;Kim, Seog K.;Kim, Jong-Moon
    • Bulletin of the Korean Chemical Society
    • /
    • v.29 no.8
    • /
    • pp.1533-1538
    • /
    • 2008
  • Porphyrins generally bind DNA in two different ways with respect to the mixing ratio; monomeric binding at a low mixing ratio and outside stacking at a high mixing ratio. In the present study, CTDNA binding property of a planar structured porphyrin, 5,10,15,20-tetrakis(N-methyl-4-pyridin-4-yl-phenyl)porphyrin (referred to as B-TMPyP) was investigated using absorption, CD, LD, and $LD^r$ spectroscopies. B-TMPyP produced a bisignate CD band, even at the lowest mixing ratio, indicating that B-TMPyP may not have a monomeric binding mode. From the observations of the spectral changes to the absorption, CD, and LD spectra in mixing ratio dependent titrations, B-TMPyP seems to have a quite different stacking type compared to that for the binding of $H_2$TMPyP. Moreover, B-TMPyP produced a CD band of opposite shape in the Soret band region. A qualitative explanation for the observed optical differences is also given.

Cu(II) Complexes Conjugated with 9-Aminoacridine Intercalator: Their Binding Modes to DNA and Activities as Chemical Nuclease

  • Kim, Jung-Hee;Youn, Mi-Ryung;Lee, Young-Ae;Kim, Jong-Moon;Kim, Seog-K.
    • Bulletin of the Korean Chemical Society
    • /
    • v.28 no.2
    • /
    • pp.263-270
    • /
    • 2007
  • New mono- and bis-Cu(II)-triazacyclononane(tacn) complex that conjugated with 9-aminoacridine were synthesized, and their binding modes and DNA cleavage activity were investigated in this study. When the classic intercalator, 9-aminoacridine, was conjugated to mono- and bis-Cu(II)-tacn complexes, a significant red-shift and hypochromism in absorption spectrum was apparent in the acridine absorption region upon binding to DNA. Furthermore, the magnitude of the negative reduced linear dichroism signal in the substrate absorption region appeared to be larger than that in the DNA absorption region. These spectral observations indicated that the acridine moiety intercalated when the Cu(II)-tacn complex was conjugated. In contrast, from a close analysis of the circular and linear dichroism spectrum, the aminoacridine-free bis-Cu(II)-tacn complex was concluded to bind at the phosphate groups of DNA. The 9-aminoacridine-free-bis-Cu(II)-tacn complex produces the nicked and linear DNA. On the other hand, 9-aminoacridine conjugated mono-and bis-Cu(II)-tacn complexes showed unspecific binding with negligible DNA cleavage.

Changes in Adrenal Angiotensin II Receptors in Renin-dependent Hypertensive Rats

  • Lee, Sung-Hou;Lee, Byung-Ho;Shin, Hwa-Sup
    • Archives of Pharmacal Research
    • /
    • v.18 no.3
    • /
    • pp.169-172
    • /
    • 1995
  • The changes in blood pressure may relate to the alterations of the responsiveness to vasoconstrictors and vasodilators, and these alterations can arise the modifications in the properties of angiotensin II (AII) receptor. In order to examine the changes of AII receptor in the hypertensive mechanism of renin-dependent hypertensive rats (RHRs; two-kidney, one-ligated type), we compared the equilibrium binding characteristics of $[^3H]$All in adrenal cortex and medulla from RHRs and normotensive rats. The dissociation constants of AII binding in both tissues of RHRs were very similar to those in the respective tissue of normotensive rats. However, the maximum binding was increased from 805 to 1050 fmole/mg protein in the adrenal cortex of RHRs, and decreased from 172 to 126 fmole/mg protein in the adrenal medulla of RHRs. These results imply that the up- and down-regulation of the All receptor population on the cell surface of adrenal glands from RHRs are consorted with the elevation of blood pressure and the activation of renin-angiotensin system.

  • PDF