• 한국식품과학회지
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• 제29권6호
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• pp.1101-1104
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• 1997

참기름의 향기성분을 dynamic headspace법으로 포집 한 다음 FID와 OD가 장착된 GC-MSD로 분석 하였다. 주요 향기성분으로는 methylpyrazine, acetic acid, 2-furan carboxaldehyde 및 2-furanmethanol 등 20종이 분리동정되었다. Sniffing test 결과 pyrazine류와 2-furan carboxaldehyde은 참기름의 좋은 향을 나타내었고 acetic acid와 2-furanmethanol은 참기름의 좋지않은 냄새로 밝혀졌다.

• Bulletin of the Korean Chemical Society
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• 제17권3호
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• pp.295-299
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• 1996

• Archives of Pharmacal Research
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• 제21권6호
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• pp.787-789
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• 1998

Dimethyltetrahydrofuran cis-2,5-dicarboxylate a furan derivative has been isolated from the fruits of Cornus officinalis, and it was isolated for the first time in the nature. The structure was elucidated by NMR spectroscopic techniques.

• 대한화학회지
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• 제50권5호
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• pp.420-423
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• 2006

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2585-2591
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• 2012

A series of heterocyclic chalcone derivatives bearing heterocycles such as thiophene or furan ring as an isostere of benzene ring were carefully prepared, and the influence of heterocycles on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities was systematically investigated. Structure-activity relationships (SAR) analysis showed that the activities of thiophene ring-containing chalcones were higher than those of furan ring-containing chalcones, and the presence of methyl substituent of heterocyclic ring distinctly affected the activities compared with non-substituted heterocycles in an opposite manner, with the 4'-methyl group of thiophene ring increasing activity and the 3'-methyl group of the furan ring decreasing activity. The distinct isosteric effect of heterocycles (i.e., thiophene or furan ring) on radical scavenging activities of heterocyclic chalones was distinctly demonstrated in our work.

• 대한화학회지
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• 제24권6호
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• pp.421-425
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• 1980

Cu(Ⅱ) 이온이 교환된 zeolite Y에 푸란이 흡착되는 형태를 알아보기 위해, 푸란과 2-메틸푸란이 흡착될 때 나타나는 EPR 스펙트럼을 조사하였다. 푸란이 흡착되면, Cu(Ⅱ) 이온의 흡수 피이크는 감소되면서 g-factor가 2.002, 피이크폭이 8 gauss인 단일 흡수피이크가 나타난다. 메틸기가 치환된 2-메틸푸란이 Cu(15)Y에 흡착되면, 푸란고리 및 메틸기의 수소에 의한 초미세구조가 나타나며, 구리의 이온 교환도가 커지면, 초미세구조는 약해진다. 푸란이 Cu(Ⅱ) 이온이 교환된 zeolite Y에 흡착되어 나타나는 새로운 흡수피이크는 Cu(Ⅱ) 이온과 푸란고리사이에 형성된 전하이동착물에 의한 것으로 생각되었다.

• 대한화학회지
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• 제38권10호
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• pp.749-752
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• 1994

하와이 Pohnpei에서 채집한 soft coral Sinularia lochmodes로부터 2개의 furanosesquiterpenes인 (5'E)-5-(2',6'-dimethylocta-5',7'-dienyl) furan-3-carboxylic acid (1)와 (1'E,5'E)-5-(2',6'-dimethylocta-l',5',7'-trienyl) furan-3-carboxylic acid (2)가 검출되었다. 이들의 구조를 $^1H$ , $^{13}C$ NMR, Homo-COSY, $^1H$-$^{13}C$ (1 bond) Heteronuclear Multiple Quantum Coherence Spectroscopy (HMQC), $^1H$-$^{13}C$ (2 and 3 bond) Heteronuclear Multiple Bond Coherence Spectroscopy (HMBC), Electron Impact Mass Spectroscopy (EI-ms) 및 Infrared Spectroscopy (IR)에 의해 밝혔다.

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.423-428
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• 2009

The comparative study of three calix[4]heterocycles (calix[4]pyrrole, calix[4]furan, and calix[4]thiophene) has been theoretically performed by using high-level density functional theory (DFT) at the MPWB1K/6-311G$^{**}$//B3LYP/6- 311G$^{**}$ level. The effect of different hetero-atoms (nitrogen, oxygen, and sulfur) placed in the heterocycles on the conformational flexibility, thermodynamic stability order, cavity sizes, charge distributions, and binding propensities are examined. The thermodynamic stability differences between the conformers are found to be much greater in calix[4]pyrrole compared to those in calix[4]furan and calix[4]thiophene. Relatively larger NH group and higher dipole of a pyrrole ring in calix[4]pyrrole contribute to the higher energy barrier for the conformational conversions and relatively rigid potential energy surface compared to the case of calix[4]furan and calix[4]thiophene. The computational results herein provide theoretical understanding of the conformational flexibility and the thermodynamic nature which can be applied to understand the complexation behavior of the three calix[4]heterocycles.

• 대한화학회지
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• 제42권4호
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• pp.391-397
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• 1998

퓨란 고리를 포함하는 bis-furan lexitropsin에서, DNA minor groove의 염기쌍과 결합하는 중요 부분인 퓨란의 기하학적 구조를 반경험적 방법(MNDO)과 ab initio(Hartree-Fock) 방법으로 최적화 시켰다. 최적화된 구조에 대해 6-31G와 $6-31G^{\ast}$ basis set을 사용하여 전자적 구조와 양성자 친화도를 구하였다. 아울러 퓨란의 양성자 친화도에 미치는 치환기 효과를 알아보기 위해 전자를 주는 기와 전자를 끄는 기를 갖는 여러 치환 퓨란에 대해 양성자 친화도를 조사하였다. 그 결과 전자를 주는 기는 퓨란의 양성자 친화도를 증가시키는 반면 전자를 끄는 기는 양성자 친화도를 감소시켰으며, 이 결과 치환 퓨란의 산소 원자의 atomic charge와 전자밀도로 설명할 수 있었다

• Bulletin of the Korean Chemical Society
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• 제18권9호
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• pp.998-1002
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• 1997

Irradiation of tert-butyl 9-anthroate and furan through a Uranium glass filter gave the [4+4] cyclodimer (21.8%) of tert-butyl 9-anthroate and furan and the 1,4-10',9' cyclodimer (4.2%) of tert-butyl 9-anthroate as well as the 9,10-10',9' cyclodimer (65.7%) of tert-butyl 9-anthroate. The [4+4] cyclodimer of tert-butyl 9-anthroate and furan was found to be thermally dissociated into their unit components with the activation enthalpy of 35.6 kcal/mole and the activation entropy of 7.6 eu, and photochemically dissociated to produce excited tert-butyl 9-anthroate. Quantum yields for the photodissociation to tert-butyl 9-anthroate and the formation of excited tert-butyl 9-anthroate in cyclohexane at room temperature were determined to be 0.56 and 0.19, respectively. The 1,4-10',9' cyclodimer of tert-butyl 9-anthroate in DMF was thermally dissociated into tert-butyl 9-anthroate with the activation enthalpy of 34.8 kcal/mole and the activation entropy of 16.4 eu. Upon irradiation, the [4+4] cyclodimers of tert-butyl 9-anthroate and the [4+4] cyclodimers of methyl 9-anthroate were quantitatively dissociated. However, no adiabatic photoreversion was observed from any of the cyclodimers. Quantum yields for the photodissociation in cyclohexane at room temperature were measured and compared.