• 대한화학회지
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• 제27권6호
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• pp.399-404
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• 1983

아미드와 아미드-용매계의 C=O stretching band에 해당하는 Raman 스펙트럼으로 부터 카르보닐기와 질소에 치환된 알킬기가 수소결합에 미치는 영향을 조사하였다. Formamide 계에서는 상호작용의 세기가 아미드-아미드>아미드-물>아미드-알코올 순으로 감소했으며, acetamide와 propionamide 계에서는 아미드-물>아미드-아미드>아미드-알코올 순으로 감소하였다. 카르보닐기에 알킬기가 치환되면 카르보닐기의 proton acceptor의 세기가 증가되며, 질소에 알킬기가 치환되면 proton donorcity가 감소함을 보이는데 이는 이론적인 계산 결과와도 일치한다.

• Bulletin of the Korean Chemical Society
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• 제34권2호
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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.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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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.

• Bulletin of the Korean Chemical Society
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• 제23권2호
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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.

• 생약학회지
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• 제20권4호
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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.

• Archives of Pharmacal Research
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• 제2권2호
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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.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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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.

• Animal Bioscience
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• 제34권10호
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• pp.1684-1694
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• 2021

Objective: This study investigated the association between feed efficiency, physicochemical properties, flavor precursors and biomolecules in the thigh meat of Korat (KR) chickens. Methods: The feed intake and body weight of individual male KR chickens were recorded from 1 to 10 weeks old to calculate the individual residual feed intake (RFI) of 75 birds. At 10 weeks of age, chickens with the 10 highest (HRFI) and lowest RFI (LRFI) were slaughtered to provide thigh meat samples. The physicochemical properties (ultimate pH, water holding capacity [WHC], drip loss) and flavor precursors (guanosine monophosphate, inosine monophosphate (IMP), adenosine monophosphate and inosine) were analyzed conventionally, and Fourier transform infrared spectroscopy was used to identify the composition of biomolecules (lipids, ester lipids, amide I, amide II, amide III, and carbohydrates) and the secondary structure of the proteins. A group t-test was used to determine significant differences between mean values and principal component analysis to classify thigh meat samples into LRFI and HRFI KR chickens. Results: The physicochemical properties of thigh meat samples from LRFI and HRFI KR chickens were not significantly different but the IMP content, ratios of lipid, lipid ester, protein (amide I, amide II) were significantly different (p<0.05). The correlation loading results showed that the LRFI group was correlated with high ratios of lipids, lipid esters, collagen content (amide III) and beta sheet protein (rg loading >0.5) while the HRFI group was positively correlated with protein (amide I, amide II), alpha helix protein, IMP content, carbohydrate, ultimate pH and WHC (rg loading >0.5). Conclusion: The thigh meat from chickens with different RFI differed in physiochemical properties affecting meat texture, and in the contents of flavor precursors and biomolecules affecting the nutritional value of meat. This information can help animal breeders to make genetic improvements by taking more account of traits related to RFI.

• Bulletin of the Korean Chemical Society
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• 제31권1호
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• pp.171-173
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• 2010

• BMB Reports
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• 제41권1호
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• pp.35-40
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• 2008

The molten globular conformation of V26A ubiquitin (valine to alanine mutation at residue 26) was studied by nuclear magnetic resonance spectroscopy in conjunction with amide hydrogen/deuterium exchange. Most of the amide protons that are involved in the native secondary structures were observed to be protected in the molten globule state with the protection factors from 1.2 to 6.7. These protection factors are about 2 to 6 orders of magnitude smaller than those of the native state. These observations indicate that V26A molten globule has native-like backbone structure with marginal stability. The comparison of amide protection factors of V26A ubiquitin molten globule state with those of initial collapsed state of the wild type ubiquitin suggests that V26A ubiquitin molten globule state is located close to unfolded state in the folding reaction coordinate. It is considered that V26A ubiquitin molten globule is useful model to study early events in protein folding reaction.