• Title, Summary, Keyword: amide

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Raman Spectroscopic Investigations of the Amide-Amide and Amide-Solvent Interactions (아미드-아미드 및 아미드-용매 상호작용에 관한 Raman 분광학적인 연구)

  • Jeong-A Yu;Young-Sang Choi
    • Journal of the Korean Chemical Society
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    • v.27 no.6
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    • pp.399-404
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    • 1983
  • Raman spectra for the carbonyl stretching mode of the amides, and amide-solvent systems have been recorded to investigate the effect of alkyl substitutions at the carbonyl carbon and at the nitrogen on the amide hydrogen-bonding. The data have shown that the interaction affinities are in the order of amide-amide > amide-water > amide-alcohol in formamide system, and amide-water > amide-amide > amide-alcohol in acetamide and propionamide systems. The strength of the proton acceptor of the carbonyl oxygen is increased by the presence of alkyl group to the carbonyl carbon and the proton donorcity of the amide is decreased by the alkyl substitution at the nitrogen. The above results are in good agreement with the ab initio SCF MO calculation.

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Combined Role of Two Tryptophane Residues of α-Factor Pheromone

  • Hong, Eun Young;Hong, Nam Joo
    • Bulletin of the Korean Chemical Society
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    • v.34 no.2
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    • pp.600-608
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    • 2013
  • Amide analogs of tridecapeptide ${\alpha}$-factor (WHWLQLKPGQPMYCONH$_2$) of Saccharomyces cerevisiae, in which Trp at position 1 and 3 were replaced with other residues, were synthesized to ascertain whether cooperative interactions between two Trp residues occurred upon binding with its receptor. Analogs containing Ala or Aib at position 3 of the peptide $[Ala_3]{\alpha}$-factor amide (2) and $[Aib_3]{\alpha}$-factor amide (5) exhibited greater decreases in bioactivity than analogs with same residue at position one $[Ala^1]{\alpha}$-factor amide (1) and $[Aib^1]{\alpha}$-factor amide (4), reflecting that $Trp^3$ may plays more important role than $Trp^1$ for agonist activity. Analogs containing Ala or Aib in both position one and three 3, 6 exhibited complete loss of bioactivity, emphasizing both the essential role and the combined role of two indole rings for triggering cell signaling. In contrast, double substituted analog with D-Trp in both positions 9 exhibited greater activity than single substituted analog with D-Trp 8 or deleted analog 7, reflecting the combined contribution of two tryptophane residues of ${\alpha}$-factor ligand to activation of Ste2p through interaction with residue $Tyr^{266}$ and importance of the proper parallel orientation of two indole rings for efficient triggering of signal G protein coupled activation. Among ten amide analogs, $[Ala^{1,3}]{\alpha}$-factor amide (3), $[Aib^{1,3}]{\alpha}$-factor amide (6), [D-$Trp^3]{\alpha}$-factor amide (8) and [des-$Trp^1,Phe^3]{\alpha}$-factor amide (10) were found to have antagonistic activity. Analogs 3 and 6 showed greater antagonistic activity than analogs 8 and 10.

Conformational Preference of Pseudo-Proline Dipeptide in the Gas Phase and Solutions

  • Park, Hae-Sook;Kang, Young-Kee
    • Proceedings of the Korean Biophysical Society Conference
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    • pp.74-74
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    • 2003
  • We report here the results on N-acetyl-N'-methylamide of oxazolidine (Ac-Oxa-NHMe) calculated using the ab initio molecular orbital method with the self-consistent reaction field (SCRF) theory at the HF level of theory with the 6-3l+G(d) basis set. The displacement of the $\square$-CH$_2$ group in proline ring by oxygen atom has affected the structure of proline, cis$\^$∼/ trans equilibrium, and rotational barrier. The up-puckered structure is found to be prevalent for the trans conformers of the Oxa amide. The higher cis populations of the Oxa amide can be interpreted due to the longer distance between the acetyl methyl group and the 5-methylene group of the ring for the trans conformer of the Oxa amide than that of the Pro amide. The changes in charge of the prolyl nitrogen and the decrease in electron overlap of the C$\^$∼/ N bond for TS structures seem to play a role in lowering rotational barriers of the Oxa amide compared to that of the Pro amide. The calculated preferences for cis conformers in the order of Oxa > Pro amides and for trans-to-cis rotational barriers in the order of Pro > Oxa amide in water are consistent with experimental results on Oxa-containing peptides. The pertinent distance between the prolyl nitrogen and the N$\^$∼/ H amide group to form a hydrogen bond might indicate that this intramolecular hydrogen bond could contribute in stabilizing the TS structures of Oxa and Pro amides and play a role in prolyl isomerization.

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NF-κB Activation and PPAR Transactivational Effects of a New Aliphatic Acid Amide from Pericarps of Zanthoxylum piperitum

  • Yang, Seo Young;Tai, Bui Huu;Song, Seok Bean;Li, Wei;Yan, Xi Tao;Sun, Ya Nan;Nguyen, Phuong Thao;Kim, Young Ho
    • Bulletin of the Korean Chemical Society
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    • v.35 no.8
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    • pp.2361-2366
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    • 2014
  • A new aliphatic acid amide, ZP-amide F (1), and eight known compounds, including bungeanumamide A (2), tumuramide C (3), ZP-amide A (4), ZP-amide B (5), ZP-amide D (6), hyperin (7), quercitrin (8), and (-)-sesamin (9), were isolated from pericarps of Zanthoxylum piperitum. The effects of these compounds on $TNF{\alpha}$-induced NF-${\kappa}B$ activation and transactivational activity of PPARs, including $PPAR{\alpha}$, $PPAR{\beta}({\delta})$ and $PPAR{\gamma}$ subtypes, were evaluated. Compounds 7 and 9 exhibited potent inhibitory effects on $TNF{\alpha}$-induced NF-${\kappa}B$ activation with $IC_{50}$ values of 5.50 and $8.10{\mu}M$, respectively. Aliphatic acid amide compounds 3, 4 and 6 displayed enhanced effects on PPAR transactivational activity with $EC_{50}$ values of 47.12, 19.13 and $12.02{\mu}M$, respectively. Among them, compound 4 demonstrated an increase in $PPAR{\alpha}$ transactivational activity, compound 3 showed a moderate increase on all PPAR subtypes, whereas compound 6 displayed weak PPAR transactivational activity.

Interfacial and Free Energy Effects in Aqueous Amide Cosolvents

  • Lee, Chi-Ho;Richard E. Lindstrom
    • Archives of Pharmacal Research
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    • v.2 no.2
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    • pp.85-88
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    • 1979
  • Data on the solubility of p-hydroxy-benzoate in amide-water cosolvent system and surface tension of the binary amide-water cosolvents are analyzed in terms of the possible mechanism for cosolvency. The results of the study suggest that strong partitioning of the alkylated amides to the ester surface, thus reducing the hydrophobic interface within the system, nay account for much of the cosolvency phenomena observed in these systems.

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A Convergent Synthesis of Bis-2-oxo Amide Triacylglycerol Analogues as Potent Lipase Inhibitors Using Acyl Cyanophosphorane Methodology

  • Lee, Kie-Seung
    • Bulletin of the Korean Chemical Society
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    • v.23 no.2
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    • pp.351-354
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    • 2002
  • A number of bis-2-oxo amide triacylglycerol analogues, a recently reported potent human gastric lipase inhibitor and its new analogues, have been prepared starting from 1,3-dibromo-2-propanol utilizing acyl cyanophosphorane methodology as a key step in a convergent manner. The key coupling reaction has been accomplished at -$78^{\circ}C$ between 1,3-diamino-2-propanol derivative and the labile diketo nitriles, derived from acyl cyanotriphenylphosphoranes upon oxidizing with $O_3$, under mild condition in moderate yields.

A New Aromatic Amide from the Roots of Aconitum pseudolaeve var. erectum (진범의 새로운 Aromatic Amide 성분)

  • Lee, Hyun-Sun;Ahn, Young-Kook;Han, Dae-Suk
    • Korean Journal of Pharmacognosy
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    • v.20 no.4
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    • pp.215-218
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    • 1989
  • A new aromatic amide isolated from the hexane soluble fraction of the root of Aconitum pseudolaeve var. erectum has been characterized as methyl-N-(2-acetaminobenzoyl) anthranilate on the basis of spectroscopic data, and a monoglyceride was also isolated and identified as glycerol-1-hexadecanoate from the fraction.

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Synthesis and Characterization of Copoly(amide-imide) Derivatives and Ultrafiltration Membrane Performances II - Permeation Properties of Copoly(amide-imide)s Ultrafiltration Membranes -

  • Jeon, Jong- young;Kim, Jong-hp
    • Korean Membrane Journal
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    • v.3 no.1
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    • pp.24-31
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    • 2001
  • Ultrafiltration membranes base on copoly(amide-imide) derivatives were prepared by the phase inversion method and the factors determining the permeation characteristics of membrane were investigated. The permeation behavior was observed by the relative ratio of permeate flux (J$\_$t/)/pure water flux (J$\_$o/). The characteristics through membrane were measured using aqueous solution of poly(ethyleneglycol) (MW 2.0$\times$10$\^$4/) over a temperature range of 10∼90$\^{C}$. With increasing the operating temperature, the relative ratio of flux became high. All the membranes had good chemical stability. Copoly(amide-imide) membranes having various Permeation properties could be obtained. Further, it was proved that the membrane performances could be determined from the preparation conditions as well as various operating conditions.

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A Study on Chemical Cyclodehydration of Aromatic Poly(ether-amide-amic acid)s (방향족 폴리(에테르-아미드-아미드산) 중합체의 화학적 탈수 고리화 반응)

  • Ahn, Young Moo
    • Textile Coloration and Finishing
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    • v.7 no.4
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    • pp.39-44
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    • 1995
  • A study has been made about some correlations in the chemical cyclization of precursors, poly(ether-amide-amic acid)s by treating in solution a mixture of acetic anhydride and pyridine in the presence of 4,4-dimethyl formamide, with the poly(ether-amic acid)s being respectively reacted between trimellitic anhydride chloride and 3 kinds of diamines, i.e., 4,4'-bis(m-aminophenoxy) benzophenone, 2,2'-bis[4-(m-aminophenoxy) phenyl] propane and 4,4'-bis(m-aminophenoxy) diphenyl sulfone. The cyclization of imide ring in the poly(ether-amide-amic acid)s may be regarded as an intramolecular acylation of amide group by o-carboxyl group. As a result of this reseach, the effects on the conversion to poly(ether-amide-imide)s have been found by changing the ratio of cosolvents in the cyclization mixture.

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