• 공업화학
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• 제25권2호
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• pp.142-146
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• 2014

9성분계 모델 콜타르 유분 중에 함유된 질소고리화합물(NHC)의 분리를 분배평형에 의해 검토했다. 원료로서는 NHC group (NHCs; quinoline (Q), iso-quinoline (iQ), indole (In), quinaldine(Qu)), 2환 방향족 화합물 group (BACs; 1-methylnaphthalene (1MN), 2-methylnaphthalene (2MN), dimethylnaphthalene (DMN)), biphenyl (Bp)과 phenyl ether (Pe)로 제조한 모델 콜타르 유분을, 용매로서는 메탄올 수용액을 각각 사용했다. 액-액 접촉 장치로서는 회분 교반기를 각각 사용했다. 평형조작 온도가 상승함에 따라 NHCs의 분배계수는 증가했으나, 역으로 BACs를 기준한 NHCs의 선택도는 감소했다. 초기 물/용매의 체적비가 감소함에 따라 BACs를 기준한 NHCs의 선택도는 급격히 감소했으나, NHCs의 분배계수는 증가했다. 일정 조건하에서, 각 group별 분배계수와 BACs를 선택도의 순서는 NHCs > Bp > BACs > Pe와 NHCs > Bp > Pe를 각각 나타냈다. 또한 전체 성분에 대한 분배계수의 순서는 In > iQ = Q > Qu > Bp > 1MN = 2MN > Pe > DMN을 나타냈다. 메탄올 추출에 의해 얻어진 NHCs의 최대 수율과 BACs를 기준한 NHCs의 최대 선택도는 각각 94%, 23이었다. 본 연구를 통해 얻어진 실험적 결과를 이용하여 콜타르 중에 함유된 NHCs의 회수공정을 검토했다.

• Applied Biological Chemistry
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• 제39권4호
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• pp.297-303
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• 1996

Aryl backbone의 ortho-위치에 (1,1-ethylenedioxy-2-fluoro)ethyl group이 치환된 일련의 제초성 (4,6-이치환-pyrimidin-2-yl)aminocarbonyl-2-(1,1-ethylenedioxy-2-fluoro)ethylbenzenesulfonamides, 1과 N-(4,6-이치환-triazin-2-yl)aminocarbonyl-2-(1,1-ethylenedioxy-2-fluoro)ethylbenzenesulfonamides, 2 유도체들을 합성하고 벼(Oryza sativa L.)를 위시하여 논 잡초인 피(Echinochloa crus-galli)와 올챙이 고랭이(Scirpus juncoides) 및 물달개비(Monochoria vaginalis pre니.)를 대상으로 측정된 제초활성$(pI_{50})$과 헤테로 고리 및 헤테로 고리상 4,6-이치환기의 변화에 따른 구조활성 관계(SAR)를 검토하였다. 그 결과 특히, 피에 대한 제초활성 조건으로 헤테로 고리는 소수성(log P<0)이, 그리고 4,6-이치환기는 분자굴절$((M_R)_{opt.}=14.58cm^3/mol)$상수가 가장 큰 영향을 미치는 요인이었다. 이들 두 상수(log P 및 MR)의 적정값(optimum value)을 만족하는 4,6-이치환기(X 및 Y)로는 dimethoxy group(1a 및 2c)이었으며 pyrimidine-치환체(1a)는 triazine-치환체(2c)보다 피에 대하여 선택적으로 양호한 제초활성$({\Delta}obs.pI_{50}=1.12)$을 나타내었다. 그리고 벼와 피에 대한 sulfonyl urea계 화합물의 선택성은 ortho-치환된 aryl backbone보다 4,6-이치환된 헤테로 고리의 구조에 의존적이었다.

• 한국균학회지
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• 제26권1호통권84호
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• pp.8-15
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• 1998

우리 나라 자연 환경에서 분리 동정된 송곳니구름버섯(Irpex zonatus) BN2 균주의 리그닌분해효소활성과 아조(azo)계, 트리페닐메탄(triphenylmethane)계 및 헤테로싸이클릭(heterocyclic)계에 속하는 몇몇 염료의 탈색능을 조사하였다. 송곳니구름버섯 BN2 균주는 lignin peroxidase(LiP)와 veratryl alcohol oxidase(VAO)를 생산하지 않고 laccase와 manganese dependent peroxidase(MnP)를 생산했다. MnP는 배양 3일부터 생산되었으나 효소활성은 매우 낮았다. 반면 laccase는 배양 초기부터 지속적으로 생산되었고 활성은 대단히 높았다. 균주를 염료와 함께 10일간 배양했을 때 아조계 염료인 orange II, orange G, tropaeolin O 및 congo red의 탈색율은 각각 98.0%, 97.4%, 99.0% 및 95.3%로 나타났고 트리페닐메탄계 염료인 basic fuchsin, malachite green 및 crystal violet 들은 98.5%, 95.7% 및 99.4%로, 헤테로싸이클릭계 염료에 속하는 eosin Y, toludine blue, methyl blue 및 azur B는 각각 97.4% 98.7%, 99.9% 및 94.0%의 탈색율을 보였다. 송곳니구름버섯 BN2 균주에 의한 염료의 탈색은 주로 laccase에 의하여 이루어진다고 생각된다.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2000년도 국제심포지움 및 추계학술대회
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• pp.45-67
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• 2000

2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) is a mutagenic and carcinogenic heterocyclic amino found in cooked meat. The in vivo mutagenicity and hepatocarcinogenicity of MeIQx were examined in mice harboring the lacZ mutation reporter gene ($Muta^{TM}$ Mice) and bitransgenic mice over-expressing the c-myc oncogene. C57B1/$\lambda$lacZ and bitransgenic c-myc (albumin promoter)/$\lambda$lacZ mice were bred and weaned onto an AIN-76 based diet containing $0.06\%$ (w/w) MeIQx or onto control diet. After 30 weeks on diet, only male bitransgenic mice on MeIQx developed hepatocellular carcinoma ($100\%$ incidence) indicating that there was synergism between c-myc over-expression and MeIQx. By 40 weeks, hepatic tumor incidence was $100\%$ ($17\%$) and $44\%$ ($0\%$) in male c-myc/$\lambda$lacZ and C57B1/$\lambda$lacZ mice given MeIQx (or control) diet, respectively, indicating that either MeIQx or c-myc over-expression alone eventually induced hepatic tumors. At either time point, mutant frequency in the lacZ gene was at least 40-fold higher in MeIQx-treated mice than in control mice of either strain. These findings suggest that MeIQx-induced hepatocarcinogenesis is associated with MeIQx-induced mutations. Elevated mutant frequency in MeIQx-treated mice also occurred concomitant with the formation of MeIQx-guanine adducts as detected by the $^{32}P$-postlabeling assay. Irrespective of strain or diet, sequence analysis of the lacZ mutants from male mouse liver showed that the principal sequence alteration was a single guanine-base substitution. Adenine mutations, however, were detected only in animals on control diet. MeIQx-fed mice harboring the c-myc oncogene showed a l.4-2.6-fold higher mutant frequency in the lacZ gene than mice not carrying the transgene. Although there was a trend toward higher adduct levels in c-myc mice, MeIQx-DNA adduct levels were not significantly different between c-myc/$\lambda$lacZ and C57B1/$\lambda$lacZ mice after 30 weeks on diet. Thus, it appeared that factors in addition to MeIQx-DNA adduct levels, such as the enhance rate of proliferation associated with c-myc over-expression, may have accounted for a higher mutant frequency in c-myc mice. In the control diet groups, the lacZ mutant frequency was significantly higher in c-myc/$\lambda$lacZ mice than in 057B1/$\lambda$1acZ mice. The findings are consistent with the notion that c-myc over-expression is associated with an increase in mutagenesis. The mechanism for the synergistic effects of c-myc over-expression on MeIQx hepatocarcinogenicity appears to involve an enhancement of MeIQx-induced mutations.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.723-728
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• 1998

The chemical behaviours of 4-methyl-2-oxo-2H-benzopyran-7-yl oxoacetyl hydrazine (2) towards some different reagents such as anhydride compounds, aromatic aldehydes, carb on disulphide, and nitrous acid yielded the corresponding pathalazine derivatives (3, 4, 5), hydrazone derivative (6), 1,3,4-oxadiazole derivative (7, 8, 9) and acid azide (10) respectively. Treatmen of 10 with absolute alcohols, amines and ethyl amino acid ester gave the corresponding carbamate derivative (11), substituted urea derivative (12) and ethyl substituted alkyl acetate (13) respectively. The biological activity of some synthesized compounds was evaluated.

• Archives of Pharmacal Research
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• 제10권1호
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• pp.14-17
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• 1987

Several new imidazo [1, 2-b] pyrazole, pyrazolo [5, 1-c]-1, 2, 4-triazine and pyrazolo [5, 1-c] triazole derivatives were prepared from the reaction of 3-antipyrinyl-5-aminopyrazole or its diazonium salt with .alpha.-chloroacetyl derivatives.

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.3136-3138
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• 2012

• Bulletin of the Korean Chemical Society
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• 제33권8호
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• pp.2581-2584
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• 2012

Hexafluoroisopropanol (HFIP) is explored as an effective medium for the synthesis of quinoxaline derivatives in high yields at room temperature. The solvent (HFIP) can be readily separated from reaction products and recovered in excellent purity for direct reuse.

• 대한화학회지
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• 제52권5호
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• pp.523-529
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• 2008

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2002년도 봄 학술발표회 논문집
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• pp.347-350
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• 2002

Wholly aromatic polybenzoxazoles(PBO) are well established as high performance materials with excellent thermal stability and mechanical properties. Heterocyclic precursor polymers such as polyhydroxyamides(PHA) have been interested in the field of high performance flame retardant polymers.[1] Precusor polymers have the advantages that they are easier to process, don't require strong solvents and can adsorb large amounts of heat energy during the cyclization process. (omitted)