• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.128-136
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• 2012

We report the solid-phase library construction of 222 number of a novel N-[alkyl sulfonamido-spiro(2H-1-benzopyran-2,4-piperidine)-6-yl] substituted amide 1A and amine 1B derivatives. The polymer-bound N-[alkylsulfonamido-spiro(2H-1-benzopyran-2,4-piperidine)-6-yl] substituted amide 9 and amine 10 derivatives were obtained by first diversity generation with various acid chlorides and alkyl halides. Further reactions on the resins 9 and 10 with substituted sulfonyl chlorides produced the desired N-[alkylsulfonamido-spiro(2H-1-benzopyran-2,4-piperidine)-6-yl] substituted amide 1A and amine 1B analogues.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.546-550
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• 2014

Relative reactivity of various carbonyl and acid derivatives in MPV-type (Meerwein-Ponndorf-Verley) reduction with an DIBAL(F) model has been studied via DFT and MP2 methods. Free energies of initial adduct formation (-Gadd) of DIBAL(F) model and carbonyls are in the order of amide < ester < aldehyde < ketone < acid chloride; in the alan-amide adduct, the developed positive charge at carbonyl carbon is expected to be stabilized by amide resonance, but in the acid chloride adduct it is destabilized by inductive effect of chloride. However the TS barrier energies (${\Delta}G_{TS}$) for the MPV-type hydride reduction of the carbonyl adducts are in the order of aldehyde < ketone < acid chloride << ester < amide; presumably decreasing order of electrophilicity of carbonyl carbon at adducts, which is well correlated with experimental data. It is noted that the relative reactivity of carbonyl derivatives in MPV-type reduction with DIBAL(X) is not governed by the alan-adduct formation energies, but follows the order of electrophilicity of carbonyl carbon of transition states.

• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2776-2782
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• 2010

Newly developed Horner-Wadsworth-Emmons (HWE) reagents 5 having triphenylphosphorane ylide subunits readily condensed with various carbonyl compounds under mild reaction conditions to afford $\beta,\gamma$-unsaturated $\alpha$-keto triphenylphorane ylides in good to excellent yields, which were hydrogenated over Pd-C (10%)/$H_2$ (1 atm) to give the corresponding $\alpha$-keto triphenylphorane ylides in quasi-quantitative yields. These triphenyphosphorane ylides have been utilized as the precursors to $\alpha$-keto amide/ester and vicinal tricarbonyl units in Wasserman's synthetic protocols, and have previously been prepared only from carboxylic acids/acid chlorides. Our new approaches provide excellent alternatives for the synthesis of triphenylphosphorane ylide precursors to $\alpha$-keto amide/ester and vicinal tricarbonyl units directly from carbonyl compounds in good to excellent yields.

• Bulletin of the Korean Chemical Society
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• v.24 no.10
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• pp.1470-1474
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• 2003

The dynamics of the tertiary conformation of myoglobin (Mb) after photolysis of carbon monoxide was investigated at 283 K solution by probing amide I and II bands using femtosecond IR absorption spectroscopy. Time-resolved spectra in the amide region evolve with 6-12 ps time scale without noticeable subpicosecond dynamics. The spectra measured at 100 ps delay after photolysis is similar to the difference FTIR spectrum at equilibrium. Time-resolved spectra of photoexcited Mb evolve modestly and their amplitudes are less than 8% of those of photolyzed MbCO, indicating that thermal contribution to the spectral evolution in the amide region is negligible. These observations suggest that the conformational relaxation ensuing photolysis of MbCO be complex and the final deoxy protein conformation have been substantially formed by 100 ps, probably with 6- 12 ps time constant.

• Macromolecular Research
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• v.12 no.3
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• pp.258-262
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• 2004

We have developed facile and rapid polycondensation reactions of N-trimellitylimido-L-leucine diacid chloride 1 with eight different derivatives of hydantoin compounds 2a-h, in the presence of a small amount of a polar organic medium, such as Ο-cresol, by using a domestic microwave oven. The polycondensation reactions proceeded rapidly-they were complete within 7-9 min-to produce a series of novel optically active poly(amide-imide)s (3a-h) in high yield with inherent viscosities of 0.33-0.51 dL/g. We characterized the resulting poly(amide-imide)s by elemental analysis, thermal gravimetric analysis (DSC, TGA, and DTG), and FTIR spectroscopy, and by measuring their viscosities, specific rotations, and solubilities. All of the polymers were soluble at room temperature in polar solvents such as N ,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, tetrahydrofuran, and N-methyl-2-pyrrolidone.

• Analytical Science and Technology
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• v.35 no.4
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• pp.143-152
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• 2022

In this review, previous studies on the synthesis and characterization of the metal Complexes with paracetamol by elemental analysis, thermal analysis, (IR, NMR and UV-Vis (spectroscopy and conductivity. In reviewing these studies, the authors found that paracetamol can be coordinated through the pair of electrons on the hydroxyl O-atom, carbonyl O-atom, and N-atom of the amide group. If the paracetamol was a monodentate ligand, it will be coordinated by one of the following atoms O-hydroxyl, O-carbonyl or N-amide. But if the paracetamol was bidentate, it is coordinated by atoms (O-carbonyl and N-amide), (O-hydroxyl and N-amide) or (O-carbonyl and O-hydroxyl). The authors also found that free paracetamol and its complexes have antimicrobial activity.

• Proceedings of the Korean Fiber Society Conference
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• 2001.04a
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• pp.189-192
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• 2001

• Journal of the Korean Chemical Society
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• v.43 no.3
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• pp.18-351
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• 1999

• Applied Biological Chemistry
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• v.51 no.2
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• pp.119-123
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• 2008

3D-QSARs (3 dimensional quantitative structrue-activity relationships) on the inhibition activities of 3-substituted-5,5'-diphenylimidazolidine-2,4-dione derivatives (1-22) against FAAH (fatty acid amide hydrolase) were studied quantitatively using CoMFA (comparative molecular field analysis) and CoMSIA (comparative molecular similarity indice analysis) methods. The statistical results of the CoMFA 1A and CoMSIA 2F model are better predictability and fitness. And also, the designed X=I, Y=$N_{2}^{+}$-substituent (P1: $Pred.pI_{50}$=6.55), according to the contour maps with information of the two models, showed the most inhibition activity against FAAH.

• Macromolecular Research
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• v.12 no.5
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• pp.528-533
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• 2004

We have prepared amide dendrons having alkyl peripheral units and various focal moieties through a convergent synthetic approach. The amphiphilic properties, due to hydrophilic amide branches and the hydrophobic peripheral units, provide an opportunity for the amide dendrons to self-organize in water. The dendritic architecture itself is also one of the critical factors in the self-organization of the amide dendrons in water. In particular, function-alization was performed at the focal point to elucidate the relationship between the focal functionality and the self-organized structures of the dendritic building blocks in the aqueous phase. The dendron having a short poly(ethylene glycol) monomethyl ether (MeO-PEG) unit (M$\_$n/ =750) as the focal moiety formed a vesicular organization in water. As the size of the hydrophilic focal MeO-PEG increased to M$\_$n/ =2,000 and 5,000, the self-organized structures became rod-type and spherical micelles, respectively. Our observation of multiple morphologies for amide dendrons is in good agreement with previous reports that indicated that the micellar structures changed from vesicles to rod-types and then to spheres upon increasing the size of the hydrophilic moiety of the amphiphiles.