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1.
Benzo[b]naphtho[2,3-d]thiophene-6,7-dicarboxylic anhydride (I) is obtained y Pschorr intramolecular cyclisation of 2-(2-aminophenylthio)-1,8-naphthalic anhydride. Condensation with alkylamines and arylamines gives the corresponding imides, which colour synthetic-polymer fibres in greenish-yellow hues, and reaction with o-phenylenediamines affords the isomer mixtures of derivatives of benzimidazo[1,2-b]-dibenzothiopheno-[4,3,2-d,e] isoquinolin-10-one and of benzimidazo-[2,1-a] dibenzothiopheno-[4,3,2-d,e]isoqumolin-10-one, which dye polyester fibres bright reddish-orange. Both series of dyes have excellent fastness to light and sublimation. The colour of the dyes is discussed in relation to the isomeric compounds derived from benzo[k,1]thioxanthene-3,4-dicarboxylic anhydride (III) and from benzo[d]naphtho[1,2-b]thiophene-9,10-dicarboxylic anhydride (II). The synthesis of the individual isomers resulting from reaction of I with o-phenylenediamine is reported and their absorption maxima related to polar factors operative within each isomer.  相似文献   

2.
孙昱  廖志远  苏龙  曾鹏 《化工进展》2014,33(8):2211-2214
研究了单种溶剂、混合溶剂对3,4-苯并芘的溶解选择性及煤沥青溶解量。并以顺丁烯二酸酐为改性剂、硫酸为催化剂,考察了溶剂效应对降低煤沥青中3,4-苯并芘的影响。研究表明,环己烷、甲苯,环己烷、乙酸丁酯组成的混合溶剂具有较好的3,4-苯并芘溶解选择性和合适的煤沥青溶解量。当环己烷∶甲苯=2∶1(体积比)和环己烷∶乙酸丁酯=2∶1(体积比)为反应溶剂时,能够高效地脱除煤沥青中3,4-苯并芘,煤沥青中3,4-苯并芘降低率分别达到88.26%和90.83%。其原因认为是此类溶剂能使包裹在沥青颗粒内部的3,4-苯并芘释放出来,且3,4-苯并芘与改性剂能够形成均相反应体系,大部分不具有致癌性的高相对分子质量环芳烃与改性剂之间形成两相体系,从而提高了改性剂与3,4-苯并芘的有效反应。  相似文献   

3.
钟江春  边庆花  王敏 《化学试剂》2005,27(4):241-242
以2-氯-3,5-二硝基苯甲酸为起始原料,经过取代、酯化、还原重氮化等反应,合成了苯并[1,2,3]噻二唑-7-羧酸乙酯。并采用二异丁基氢化铝将其一步还原制备了苯并[1,2,3]噻二唑-7-醛。  相似文献   

4.
Abstract

The thermodynamic stabilities of all possible arene oxides of benzo[a]pyrene and benzo[e]pyrene, and of the two parent compounds, have been obtained using semiempirical AM1 and molecular mechanics calculations. The calculations predict that all K-region epoxides are highly stabilized compared to other epoxides for both PAHs. The terminal ring epoxides include proximal and distal types, either close to or remote from the bay-region, respectively. The distal epoxides correspond to the necessary first intermediates in the enzymatic activation process leading to the ultimate bay-region dihydrodiol epoxide carcinogens. There are marked differences in the calculated heats of formation of the distal benzo[a]pyrene-7,8-epoxide and benzo[e]pyrene-9,10-epoxide (compared to either the respective parent PAHs or the K-region epoxides) favoring the epoxide from benzo[a]pyrene. One can propose that these thermodynamic differences may be a principal factor responsible for facile initiation of the activating metabolic pathway mediating the carcinogenicity of benzo[a]pyrene, and the blocking of the corresponding mechanism in benzo[e]pyrene.  相似文献   

5.
The formation of hemoglobin - carcinogen adducts has been detected in carcinogen treated animals and in human populations. Although polynuclear aromatic hydrocarbons are ubiquitous in the human environment and DNA - aromatic hydrocarbon adducts have been detected in human tissue, the occurrence of hemoglobin - polynuclear aromatic hydrocarbon adducts in humans has not been thoroughly described. In this study we examined the effects of reaction condition on the extent of in vitro reaction of human hemoglobin and (+) [3H]benzo[a]pyrene-7,8-diol-9,10-epoxide (anti)(BPDE), a metabolite thought to be largely responsible for the carcinogenic effect of benzo[a]pyrene. The chromatographic properties of the resulting hemoglobin - BPDE adducts were examined by conventional DEAE-cellulose ion exchange liquid chromatography and by reversed phase high performance liquid chromatography. Several adducts were formed which were chromatographically resolved from hemoglobin and from the individual globins. We applied these techniques to the qualitative and quantitative assessment of benzo(a)pyrene hemoglobin adducts in smokers, correlating both maternal and fetal adducts with smoking status.  相似文献   

6.
We have synthesized undecacyclic aromatic hydrocarbons using condensation of dibenzoanthrones. For example, dibenzo[ a,o ]dinaphtho[3,2,1- cd ;1,2,3- lm ]perylene, diphenanthra[1,2,3- cd ; 3,2,1- lm ]perylene and diphenanthra[2,3,4- cd ;4,3,2- lm ]perylene were produced from 5,6-, 8,9- and 10,11-dibenzoanthrones, respectively. In the present study, we have extended our work and aimed to synthesize new undecacyclic aromatic hydrocarbons by the use of 9,10-dibenzoanthrone (7 H -benzo[ de ]naphthacene-7-one) as a starting material. 9,10-Dibenzoanthrone was prepared by the cyclization of 1,2'-dinaphthylketone in aluminum chloride anhydride and sodium chloride, and the structure was confirmed by NMR measurements. It dissolves into ethanol and crystallizes in pale yellow needles; its melting point is 198.2-199.3°. The condensation of 9,10-dibenzoanthrone should give undecacyclic aromatic hydrocarbons such as benzo[ vwx ]naphtha[12,1,2- cde ] hexaphene.  相似文献   

7.
Efficient syntheses of important metabolites of 7,12-dimethylbenz[ a ]anthracene (DMBA) and benzo[ c ]chrysene (B[ c ]C), via Suzuki coupling reaction are described. This approach provides an excellent method for the preparation of 3-methoxy-DMBA 5 , 10-methoxy-B[ c ]C 14 and 2-methoxy B[ c ]C 20 , and hence for the corresponding dihydrodiols 6 , 15 , and 21 . Following a similar Suzuki reaction, DMBA-6(5 H )-one 8 was also synthesized in high yield.  相似文献   

8.
用聚合物试剂减少煤沥青中3,4-苯并芘的研究   总被引:1,自引:0,他引:1  
研究了用聚合物同煤沥青反应降低其中3,4-苯并芘的方法。实验采用3种聚合物同煤沥青反应,得出不同的聚合物对减少3,4-苯并芘的作用效果,通过对聚苯乙烯-丁二烯-苯乙烯、古马隆-茚树脂和聚乙二醇的研究发现:添加4%的古马隆-茚树脂对煤沥青中3,4-苯并芘的脱除效果较好,脱除率达到46.78%,最佳反应温度为270℃,煤沥青中的3,4-苯并芘的质量分数由1.43%降低到0.76%。  相似文献   

9.
亓金萍 《广东化工》2010,37(6):266-267
文章介绍了苯并呋喃的生物活性研究及最新应用,并综述了近几年来苯并呋喃类化合物结构骨架的构建与合成方法。  相似文献   

10.
Condensation of 4–chloro–l, 8–naphthalic anhydride with 2–nitrophenol afforded 4–(2–nitrophenoxy)–l, 8–naphthalic anhydride, which on reduction followed by Pschorr intramolecular cyclisation gave benzo[k, l]xanthene–3, 4–dicarboxylic acid anhydride. The identity of the product was confirmed by its alternative synthesis from 5–amino–4–phenoxy–l, 8–naphthalic anhydride. Benzo[k, l]xanthene–3, 4–dicarbox–ylic acid anhydride condensed with alkylamines or arylamines and with o–phenylenediamines to yield the corresponding imides and imidazole derivatives, which coloured polyester in fluorescent greenish–yellow to orange hues, respectively, of good fastness to light and sublimation. The colour of the dyes is discussed with respect to analogous ring–closed sulphur– containing heterocycles.  相似文献   

11.
Non white rot fungi isolated from fuel-contaminated soil were screened for their ability to grow with benzo[a]pyrene as sole carbon source. The capacity of one isolate identified as F. solani F33 was further investigated by studying the mineralization of [7,10-14C]benzo[a]pyrene. Spores of F. solani were able to germinate in presence of benzo[a]pyrene and growing mycelium mineralized [7,10-14C]benzo[a]pyrene (0.2% over a period of 10 days). The amount of 14CO2 released decreased of 66% in 10 days culture in the presence of the inhibitor of cytochrome P-450 1-aminobenzotriazole, suggesting that such enzymes are involved in benzo[a]pyrene degradation by F. solani. This hypothesis was also enhanced by observing, in F. solani grown on benzo[a]pyrene, the presence of small vesicles with high  相似文献   

12.
A four-step route was designed to synthesize 3,8-benzo[c]cinnoline dicarboxylic acid (4). New conjugated polymers, POXD (I) and POXD (T), containing benzo[c]cinnoline and oxadiazole moieties, were obtained by thermal cyclodehydration of their soluble polyhydrazide precursors PHA (I) and PHA (T), respectively. Two reduction peaks were observed for these new conjugated polymers during CV cathodic scan. From the CV voltammograms combined with the results from molecular simulation, we concluded that the first reduction occurred at oxadiazole moiety and benzo[c]cinnoline moiety was responsible for the second reduction. It indicates that oxadiazole has stronger electron affinity than benzo[c]cinnoline. We proposed a mechanism to explain this two-stage reduction process. Due to the planar and electron-accepting ability of benzo[c]cinnoline and oxadiazole moieties, POXD (I) and POXD (T) exhibited very low LUMO (−3.42 and −3.45 eV) and HOMO (−6.23 and −6.27 eV) energy levels. They can be used as hole-blocking or electron-injection layers for OLED applications.  相似文献   

13.
Synthesis of benzo[a]fluorene, benzo[c]fluorene, and benzo[j]fluoranthene have been accomplished from readily accessible enol ether precursors via a Lewis acid-catalyzed Prins-type cycloaromatization. Mechanistically, it was proposed that Lewis acids catalyze the generation of oxonium species, which accelerate subsequent annulation and aromatization. This protocol offers the benefit of an operationally simple, transition-metal-free, and air-tolerant reaction condition, enabling gram-scale syntheses of the desired products. The total synthesis of viridistratin A further supported this synthetic strategy for establishing polycyclic aromatic hydrocarbon architectures.  相似文献   

14.
Thermolysis of 2,3-dicyano-bicylo[2,2,1]hept-5-ene-2,3-dicarboxylic anhydride ( 6 ) at 580-590 °C or of 3,4,5,6-tetraazidophthalic anhydride ( 9 ) at 110 °C affords 3,4-dicyanomaleic anhydride ( 1 ).  相似文献   

15.
To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1′-biphenyl]-2,2′-dicarboxylic acid, were selected as the solutes, and the extraction equilibrium of the acids were studied with 1-octanol, 50% tributyl phosphate (TBP) in kerosene, and 10% trialkylphosphine oxide (TRPO) in kerosene. The results showed that the degree of extraction of [1,1′-biphenyl]-2,2′-dicarboxylic acid was larger than that of trimellitic acid for all of the solvent, and the extraction capacity with TRPO is more effective than the one with TBP. The extraction behavior of aromatic polyacid is different from that of carboxylic acid, and the reactive extraction function of aromatic acids with TBP and TRPO is not as effective as that of carboxylic acid. 1-octanol could be used to remove [1,1′-biphenyl]-2,2′-dicarboxylic acid from the mixture of trimellitic acid and [1,1′-biphenyl]-2,2′-dicarboxylic acid. Because the weak hydrogen bond association exists between -OH in 1-octanol and -COOH in aromatic acid, the extractive selectivity of [ 1, 1′-biphenyl]-2,2′-dicarboxylic to trimellitic acid depends on the stoichiometric ratio.  相似文献   

16.
4′-tert-Alkylbenzo[15]Crown-5-Ether. Syntheses and Complexes with Potassium Thiocyanate The title compounds 4 are synthesized either by alkylation of pyrocatechole 1 in 4-position and followed by ring closure with 1,11-dichloro-3,6,9-trioxaundecane or by alkylation of benzo[15]-crown-5 3 . In most cases the way first mentioned gives better results. Analytical samples of the alkylated benzo[15]crown-5 ethers 4 are obtained through complexing with KSCN. Physical data and 1H-n.m.r.-spectra of 5 new pyrocatecholes 2 and 6 new benzo[15]crown-5 ethers 4 are given.  相似文献   

17.
This article describes the photooxidation of benzo[ de ]naphtho-[2,1,8,7- stuv ]anthra[2,1,9,8- hijkl ]pentacene (BNAP) synthesized by the condensation of naphthanthrone with zinc dust. When an o -dichlorobenzene solution of BNAP was irradiated with light of its maximum absorption wavelength (535 nm), the original absorption band was reduced and a new band appeared at longer wavelengths showing a peak at 606 nm. Excitation of the photobleached sample with 600 nm gave rise to fluorescence on the red side of that of BNAP by about 90 nm. The new fluorescence spectrum showed a vibrational progression of about 1,600 cm m 1 , which corresponds to the stretching of a carbonyl group. No spectral changes occurred in degassed solution. These findings suggest that BNAP reacts with singlet oxygen to form a ketone. Molecular orbital calculations revealed that the carbonyl group of the product is located at the C-18 position and that a hydroxy group is also present at the C-2 position; therefore the product is predicted as 2,18-dihydrobenzo[ de ]-naphtho[2,1,8,7- stuv ]anthra[2,1,9,8- hijkl ]pentacen-18-one.  相似文献   

18.
用丙酮作溶剂超声波抽提垃圾焚烧炉飞灰中苯并[a]芘有机物,再用固相萃取纯化,然后利用配ODS3C18色谱柱的高效液相色谱仪,在以90%乙腈+10%水为流动相,流速为1mL/min,激发波长246nm和发射波长431nm的条件下测定了垃圾焚烧炉飞灰中的苯并[a]芘含量。结果表明:该方法检出限为0.01ng/mL,苯并[a]芘的回收率90.8%,方法的RSD(相对标准偏差)为3.89%。  相似文献   

19.
Preparation of Benzo[c]thiophenes Using a Modified Hinsberg-Reaction Whereas the tetrahydrobenzo[c]thiophenes 3 and 6 are easily obtained from 1 and 2 or 4 their dehydrogenation (i. e. aromatization) is difficult and the yields are low. However, the method allows to prepare hitherto unknown benzo[c]thiophenes with special substituents in the 1,3-positions.  相似文献   

20.
Polycyclic aromatic hydrocarbons (PAHs) occur in the environment as complex mixtures including compounds with mutagenic and carcinogenic activity. The PAH profile routinely determined in environmental samples at present encompasses isomers with molecular weight (MW) not greater than 300. However, PAHs with MW >300 have been demonstrated for several matrices to contribute up to 50% of the total activity when tested for carcinogenicity in experimental animals. Recent studies indicate that among the dibenzopyrenes with MW 302 dibenzo[a,l]pyrene, possessing a fjord region, is by far the most carcinogenic PAH hitherto identified. To further elucidate the environmental relevance of this compound we have applied the isotope dilution GC/MS technique as analytical procedure to determine this compound and the related fjord region PAH naphtho[1,2-a]- and naphtho[1,2-e]pyrene in various matrices. Identification was based on comparison of UV and mass spectra as well as retention times of authentic reference materials. Determination of these PAHs was achieved after clean-up by several chromatographic steps including fractionation on a modified TABA-silica gel column. Quantitative data for matrices such as two cigarette smoke condensates, motor vehicle exhaust condensate (Otto-type engines), and tar-cork are reported. Based on toxic equivalent factors the relative contribution of dibenzo[a,l]pyrene (5.4–42.3%) to the total carcinogenic activity of a PAH profile will be discussed comprising 14 selected isomers (benzo[b]naphtho[2,1-d]thiophene; cyclopenta[cd]pyrene; benz[a]anthracene; chrysene/triphenylene; sum of benzo[b]-, benzo[k]-, and benzo[j]fluoranthene; benzo[a]pyrene; indeno[1,2,3-cd]pyrene; dibenz[a,h]anthracene; benzo[ghi]perylene; anthanthrene; dibenzo[a,l]pyrene determined in these matrices.  相似文献   

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