• 대한화학회지
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• 제32권3호
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• pp.163-170
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• 1988

N-methyl formamide, N,N-dimethyl formamide, N-methyl acetamide, 및 N,N-dimethyl acetamide의 여러 형태에 대한 상대에너지를 MNDO법으로 구하여 C-N결합 및 메틸기 회전에 대한 회전장벽에 미치는 1-전자 및 입체 반발에너지의 영향을 논의하였다. 그 결과 formamide의 형태안정화는 주로 1-전자 에너지항에 의하여 결정되고, acetamide의 형태안정화는 주로 입체인자항에 의하여 결정됨을 알았다. C-N 결합에 대한 회전장벽을 구한 결과 N-methyl formamide와 N-methyl acetamide에서 입체 장애 효과는 바닥상태에서 보다 전이상태에서 크게 작용하지만 N,N-dimethyl formamide와 N,N-dimethyl acetamide에서 입체장애 효과는 전이상태에서 보다 바닥상태에서 더 크게 작용함을 알았다.

• 한국식품영양과학회지
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• 제10권1호
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• pp.85-91
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• 1981

S. aureus를 TCA로 처리(處理)하여 저분자물질(低分子物質)을 추출(抽出)한 후(後) STS법(法)에 준(準)하여 지질핵산(脂質核酸), 단백질(蛋白質) 및 잔사(殘渣)로 분획(分劃)하였다. 이와 아울러 초음파처리(超音波處理)로 균체(菌體)를 파쇄(破碎)한 후(後) 원심(遠心)침전을 SDS 및 Formamide를 사용(使用)하여 축차적(縮次的)으로 가용성(可溶性) 획분(劃分)을 추출(抽出)하고 얻어진 각(各) 획분(劃分)의 성질(性質)을 조사(調査)하였다. 그 결과(結果), 초음파(超音波)로 파쇄(破碎)한 균(菌)의 원심상징액(遠心上澄液)에서 균체(菌體) DNA의 91.3%가 검출(檢出)되었고 원심침전(遠心沈澱)으로부터는 SDS 처리(處理)에 의(依)하여 높은 비활성(比活性)(13.67unit/mg Protein)의 Malate dehydrogenase가 유지되었다. 한편, SDS 처리균(處理菌)의 원심침전물(遠心沈澱物)을 다시 열(熱) Formamide $150^{\circ}C$로 추출(抽出)하고 가용성획분(可溶性劃分) 및 잔사(殘渣)를 각각(各各) 산(酸) 가수분해(加水分解)한 후(後) Paper chromatsgraph하여 잔사(殘渣)로부터 Glucosamine을 확인(確認)하였다. 그러나 가용성획분(可溶性劃分)은 Ninhydrin반응(反應)에는 음성(陰性)이었고 환원당반응(還元糖反應)은 음성(陰性)이었다. 이상(以上)의 결과(結果)로 부터 초음파(超音波)로 파쇄(破碎)한 균체(菌體)의 원심상징액(遠心上澄液)은 주(主)로 원형질획분(原形質劃分)이며 SDS 및 Formamide에 의(依)하여 용출(溶出)되어 나온것은 각각(各各) 원형질막(原形質膜) 및 세포벽(細胞壁)의 Polysaccharide 획분(劃分)으로, Formamide 불용성분(不溶性分)은 Peptidsglycan 획분(劃分)으로 판정(判定)되었다.

• 산업기술연구
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• 제6권
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• pp.49-55
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• 1986

A rapid and simple test to distinguish halloysite from kaolinite in mineral mixtures has been developed based on differences in the rate and extent of formamide intercalation. The results of quantitative analysis by formamide intercalation reaction GEC contained 90% of kaolin minerals, GEC contained of 86% of halloysite and GYK contained of 59% kaolinite. The extent of formamide intercalation by kaolinite was likely influenced by sample crystallinity.

• Bulletin of the Korean Chemical Society
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• 제12권1호
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• pp.22-26
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• 1991

Potential energy surfaces for the proton transfer in a formamide dimer have been obtained by ab initio SCF calculations with STO-3G, 3-21G, and 4-31G basis sets and several features have been discussed. Energy minima for a formamide dimer and its tautomer are varied with basis sets. But the general features of the potential energy surfaces are similar among them.

• Bulletin of the Korean Chemical Society
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• 제10권6호
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• pp.488-491
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• 1989

Theoretical studies on the proton transfer reaction in a formamide dimer have been done by Ab initio SCF calculation. In this study, we have shown several effects on the potential energy profile of the proton transfer in a formamide dimer, such as the effect of a basis set, the effect of a geometry optimization, and the effect of a distance between proton-donor and proton-acceptor.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.91-98
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• 2015

Formamide의 중성가수분해 mechanism은 QM/MM (quantum mecahnics/molecular mechanics) molecular dynamics simulations 및 CPMD과 같은 방법으로 연구되어왔다. 본 연구에서는. Umbrella sampling을 이용한 QM/MM-MD simulation을 사용하여 4가지 반응의 free energy surface를 도출해냈다. 전체적으로, 가장 선호되는 메커니즘은 two step으로 구성된 water assisted stepwise mechanism이었으며 모든 mechanism은 ab-initio calculation과 QM/MM-MD simulation이 수행되었다. water assisted stepwise mechanism을 살펴보면, 첫 번째 step에서 formamide의 carbonyl group이 hydrate되면서 gem-diol intermediate를 형성한다. 다음 step에서, intermediate의 hydroxyl group으로부터 amino group으로 water-assisted proton transfer이 일어난다. 두 반응 모두에서 물이 proton transfer를 직접적으로 도와주는 것을 관찰할 수 있었다. 특히, ab-initio calculation과는 다르게 QM/MM-MD에서는 gem-diol intermediate가 안정화되는 것으로 solvent effect를 잘 보여준다.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3634-3640
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• 2011

We have performed quantum mechanical calculations to study the geometries and binding energies of biologically important, cyclic hydrogen-bonded complexes, such as formic acid + $H_2O$, formamidine + $H_2O$, formamide + $H_2O$, formic acid dimer, formamidine dimer, formamide dimer, formic acid + formamide, formic acid + formamidine, formamide + formamidine, and barrier heights for the double proton transfer in these complexes. Various ab initio, density functional theory, multilevel methods have been used. Geometries and energies depend very much on the level of theory. In particular, the transition state symmetry of the proton transfer in formamidine dimer varies greatly depending on the level of theory, so very high level of theory must be used to get any reasonable results.

• Journal of Microbiology and Biotechnology
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• 제16권4호
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• pp.637-638
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• 2006

Bioassay-guided fractionation of an organic extract of the culture broth from an unidentified marine-derived fungus led to the isolation of a new metabolite, N-[2-(4-hydroxyphenyl) acetyl]formamide (1), along with four known polyketides, 4-hydroxyphenyl acetamide (2), 4-hydroxyphenyl acetic acid (3), 3,4-dihydroxyphenyl acetic acid (4), and N-[2-(4-hydroxyphenyl)ethenyl]formamide (5). The structures of 1-5 were elucidated by spectral data analyses. Among them, compounds 1, 4, and 5 exhibited significant radical scavenging activity against 1, 1-diphenyl-2-picrylhydrazyl (DPPH) with $IC_{50}$ values of 8.4, 11.9, and $0.2{\mu}M$, respectively.

• Korean Chemical Engineering Research
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• 제55권4호
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• pp.520-529
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• 2017

Viscosity data were measured at 298.15 K and 308.15 K for formamide + 1-propanol, 2-propanol, 1-butanol, 2-methyl-1-propanol or 2-methyl-2-propanol mixtures. For an equimolar mixture, deviation in viscosity follows the sequence: 2-methyl-2-propanol >2-methyl-1-propanol>1-butanol>2-propanol>1-propanol. The viscosity data were further analyzed in terms of graph theory. Free energy of activation was also calculated from experimental viscosity data along with previously reported excess volume data. The deviation in viscosity and free energy of activation were fitted to Redlich-Kister polynomial equation. The viscosity data were also correlated by correlations like Grunberg-Nissan, Tamura-Kurata, HindMcLaughlin-Ubbelohde, and Katti-Chaudhari relation. Various adjustable parameters, $G_{12}$, $T_{12}$, $H_{12}$, and $W_{vis}/RT$, of various correlations were used to predict viscosity deviation of binary mixtures. Positive value of $G_{12}$ indicates strong interaction in the studied systems. Grunberg-Nissan relation has lowest deviation among the four correlations for formamide + 1-propanol or 2-propanol mixtures; and for mixtures of formamide with 1-butanol or 2-methyl-1-propanol, TamuraKurata has lowest deviation. Grunberg-Nissan gives lowest deviation for formamide + 2-methyl-2-propanol mixtures.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2002년도 추계총회 및 연구발표회 초록집
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• pp.111.1-111
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• 2002