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1.
A new unusual pigment with a novel carbon framework named selaginellin (1) was isolated from the acetone extract of Selaginella sinensis, and its methoxy derivative (1a) was synthesized. Both selaginellin 1 and 1a are racemic compounds. The structure of selaginellin 1 was established as (R,S)-4-[(4'-hydroxy-4-(hydroxymethyl)-3-((4-hydroxyphenyl)ethynyl)biphenyl-2-yl)(4-hydroxyphenyl)methylene]-2,5-cyclohexadien-1-one and 1a as (R,S)-4-[(4'-methoxy-4-(methoxymethyl)-3-((4-methoxyphenyl)ethynyl)biphenyl-2-yl)(4-methoxyphenyl)methylene]-2,5-cyclohexadien-1-one by the analysis of one- and two-dimensional NMR data, HR-ESIMS, EI-MS, IR, UV, CD, and single-crystal X-ray experiments, and the mechanism of their color change according to different pH values and fluorescent properties was studied.  相似文献   

2.
A novel colorimetric sensor based on 8-hydroxy quinoline-5-azo-4'-nitrobenzene (1) was prepared and used for recognizing anions. 1 and its metal complex (1.Co) were found to show response to anions such as CH(3)CO(2)(-), H(2)PO(4)(-), HSO(4)(-), F(-) and dramatic color changes were observed. The selectivity and sensitivity of 1 and 1.Co for sensing anions were different, which was in the order of CH(3)CO(2)(-)>F(-)>H(2)PO(4)(-)>HSO(4)(-) for 1 and H(2)PO(4)(-)>HSO(4)(-)>CH(3)CO(2)(-) approximately F(-) for 1.Co, respectively. In CH(3)CN, sensor 1.Co exhibited excellent specificity toward H(2)PO(4)(-), and the color variety was dependent on the concentration of H(2)PO(4)(-) which was attributed to anion structure and stability of anionic complex (1-anion), metal complex (1-Co) and inorganic complex (Co-anion).  相似文献   

3.
Oxidation of the tetraarylpinacols (Ar(2)COH)(2), 1a-e, in which Ar = C(6)H(5) (1a), 4-ClC(6)H(4) (1b), 4-MeC(6)H(4) (1c), 4-MeOC(6)H(4) (1d) and 4-Me(2)NC(6)H(4) (1e), by thianthrene cation radical (Th(*+)) in CH(3)CN and in CH(2)Cl(2) led quantitatively to the corresponding diaryl ketones Ar(2)C=O (2a-e), provided a sufficient amount of base, 2,6-di-tert-butyl-4-methylpyridine (DTBMP), was present to prevent presumed acid-catalyzed rearrangement. In the case of 1e, continued oxidation of 2e was also observed. Oxidation of 1a by (4-BrC(6)H(4))(3)N(*+)SbCl(6)(-) and (4-BrC(6)H(4))(3)N(*+)SbF(6)(-) (Ar(3)N(*+)) occurred analogously. Evidence for the catalytic, cation-radical rearrangement of 1a by Ar(3)N(*+) (reported in earlier literature) and by Th(*+) could not be found. Quantitative oxidation of 1a to 2a and of 1d to 2d was obtained also with NOBF(4), again provided that sufficient DTBMP was present to prevent acid-catalyzed rearrangement. Catalytic, oxidative rearrangement of 1d at room temperature and (as reported in earlier literature) at -5 degrees C was not observed. Oxidation was also observed of 2,3-diphenyl-2,3-butanediol (3) to acetophenone (9) and of 1,1-dimethyl-2,2-diphenylethanediol (4) to 2a and acetone by Th(*+). Oxidation of 2,3-dimethyl-2,3-butanediol (5) by Th(*+) was not observed. Instead, even in the presence of DTBMP, pinacolone (10) and tetramethyloxirane (11) were formed, through, it is proposed, a mechanism involving complexation with Th(*+).  相似文献   

4.
合成双酚AF的新方法   总被引:5,自引:1,他引:4  
戴燕  吕春绪  李斌栋  李晶晶 《应用化学》2009,26(11):1292-1296
由六氟丙酮三水合物和苯胺,经缩合、重氮化、水解、Friedel-Crafts烷基化等4步反应在常压下合成了双酚 AF。首先,以五氧化二铌为催化剂,在 n (HFA•3H2O) : n (aniline) : n (Nb2O5) = 2 : 1 : 0.1,回流 6 h 条件下,合成出中间体(Ⅰ),收率高达96.3%。然后在重氮化温度为 ﹣2 ~ 2 ℃,硫酸质量分数为 14.7%,n (Ⅰ) : n (H2SO4) : n (NaNO2) = 1 : 4.1 : 1.1,及水解时硫酸质量分数为 50%,n (H2SO4) : n (Ⅰ) = 11.0 : 1、108~112 ℃反应 1.5 ~ 2 h 的优化条件下,化合物Ⅰ经重氮化、水解后以 92.7%的高收率得到中间体 2-(4-羟基苯)六氟异丙醇(Ⅱ);再在甲磺酸存在下,化合物Ⅱ与苯酚经Friedel-Crafts烷基化反应以 72.4% 的收率合成了目标产物双酚 AF(Ⅲ),总收率为 64.6%(以苯胺为基准计算)。  相似文献   

5.
1-Trityl-4-vinylimidazole was prepared by direct tritylation of 4(5)-vinylimidazole and polymerized using a free radical initiator. Poly(1-trityl-4-vinylimidazole) was hydrolyzed using aqueous acetic acid to give poly[4(5)-vinylimidazole]. The poly[4(5)-vinylimidazole], which was obtained from the hydrolysis of poly(1-trityl-4-vinylimidazole), was compared with poly[4(5)-vinylimidazole] prepared directly from 4(5)-vinylimidazole for differences in stereochemistry. The stereochemistry of both polymers was found to be similar by high-resolution NMR. Thus, the trityl does not influence the stereochemistry of poly[4(5)-vinylimidazole]. The reaction of 1-trityl-4-vinylimidazole with n-butyllithium gave 2-lithio-1-trityl-4-vinylimidazole. This intermediate was used to prepare 2-substituted 4(5)-vinylimidazoles, which are new monomers that can be polymerized using free radical initiators.  相似文献   

6.
3, 4-Bis (trifluoromethyl)-perfluorohexene-(3) (1) reacted with diethylamine to give the 1-N, N-diethylamino-2-pentafluoroethyl -3-trifluoromethyl-perfluoropentene-(1)(2), which was easily hydrolyzed to the corresponding N, N-diethyl-2-penta-fluoroethyl- 3-trifluoromethyl-perfluoropenteno-(2)-amide (3). When compound 1 was allowed to react with n-butyl amine at 40-50`C, the 2,3,4-tris(trifluoromethyl)-4-pentafluoroethyl-1-n-butyl-aza- cyclobutene-(2) (5) was obtained as the main product and at-30-40`C, 3,4-bis(trifluoromethyl)-4-n-butylamino-perfluorohexene-(2) (4) as the main product. The isomers 3, 4-bis(trifluoromethyl)-4-allyloxy-perfluoro-hexen-(2) (6) and 2-pentafluoroethyl-3-trifluoromethyl-3-allyloxy-perfluoropentene-(1)(7) were formed when 1 was reacted with sodium allyl alcoholate.  相似文献   

7.
N1-Trifluoroethyl-4-methoxy-5-chloro-3-pyridazone (4) was synthesized by the substitution reaction of 4methoxy-5-chloro-3-pyridazone (1) with trifluoroethyl trifluoromethanesulfonate (A) at basic condition. In the most of reaction conditions, N1-methyl-4-methoxy-5-chloro-3-pyridazone (2) was obtained as a major by-product, which means that the methyl group in the 4-methoxy shifted to N-1 position inter-molecularly aided by A or trifluoroethyl methanesulfonate (B). We obtained N1-methyl-4-trifluoro-ethoxy-5-chloro-3-pyridazone (3) in the reaction of 1 with B at higher temperature in different solvents with different yield (Table 1 ), which mechanism was shown in Figure 1. When we tried to synthesize 4 in the reaction of 1 with trifluoroethyl toluenesulfonate under basic condition, 6 was obtained (Figure 2). All the detailed mechanisms are undergoing investigated.  相似文献   

8.
We report a dynamic polymerization system based on the reversible nucleophilic Michael polyaddition of activated alkynes and dithiols. Four poly(dithioacetal)s(P1-P4) were prepared via the base-catalyzed thiol-yne "click" polyaddition of two dithiols(1,4-butanedithiol(4 S) and 1,5-pentanedithiol(5 S)) and two alkynones(3-butyn-2-one(Y1) and 1-phenyl-2-propyn-1-one(Y2)) at high concentrations. We systematically investigated the base-catalyzed polymerization of 4 S and Y1(for polymer P1) under dif...  相似文献   

9.
Regioselective alkylation of 2-alkyl-5,6,7,8-tetrahydro-3H-cycloheptimidazol-4-one (1) and 2-alkyl-3H-cycloheptimidazol-4-one (2) was investigated. 3-[2'-(1-tert-Butyl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]-2-propyl-5,6,7,8-tetrahydro-1H-cycloheptimidazol-4-one (6) was preferentially obtained under the conditions by using NaH in DMF or THF. On the other hand, 3-[2'-(1-tert-butyl-1H-tetrazol-5-yl)biphenyl-4-ylmethyl]-2-propyl-5,6,7,8-tetrahydro-3H-cycloheptimidazol-4-one (5), the synthetic intermediate compound of Pratosartan, was obtained selectively in the presence of n-Bu(4)NBr in toluene by using aqueous sodium hydroxide as a base. In this reaction, it was found that the concentration of the alkaline solution influences its regioselectivity. This selectivity was observed even for aldehyde and ester derivatives.  相似文献   

10.
以2,6-二氟苯腈与吗啉反应制得2-氟-6-吗啉-苯腈(1); 1与水合肼在N-甲基吡咯烷酮中通过环合反应制得3-氨基-4-吗啉-1H-吲唑(2); 2与不同羧酸经缩合反应合成了8个新型吲唑类化合物(4a~4h),其结构经1H NMR, IR和HR-ESI-MS表征。抗肿瘤活性测试结果表明:3,4,5-三甲氧基-氮-(4-吗啉-1H-吲唑-3-基)苯甲酰胺(4a)的抗肿瘤活性最好,对K-562, SMMC7721和T-47D肿瘤细胞有明显抑制作用,IC50分别为0.056 μmol·L-1, 0.062 μmol·L-1和0.078 μmol·L-1。  相似文献   

11.
Two new glycosides, named Firmacosides A and B, together with known fatty esters, batyl alcohol, Delta(5,20) sterol and sphingosine derivatives have been isolated from the soft coral Sinularia firma TIX-DUR. On the basis of spectroscopic analysis ((1)H-NMR, (13)C-NMR, (1)H-(1)H COSY, HMQC, HMBC and FAB-MS), Firmacoside A was established as hexadecanyl-1-O-alpha-D-arabinopyranosyloxy (1-->4)-alpha-D-arabinopyranosyloxy (1-->4)-alpha-D-arabinopyranoside (1), and firmacoside B was elucidated as docosanyl-1-O-alpha-D-arabinopyranosyloxy (1-->4)-3-O-acetyl-alpha-arabinopyranosyloxy (1-->4)-alpha-D-arabinopyranoside (2).  相似文献   

12.
吲哚和2,4-二氯嘧啶经偶联反应制得3-(2-氯嘧啶-4-基)-1H-吲哚(1); 1与CD3I 经取代反应制得3-(2-氯嘧啶-4-基)-1-(甲基-d3)-吲哚(2); 2经两步亲核取代反应制得N′-(2-二甲基氨基乙基)-2-甲氧基-N′-甲基-N-{[4-(1-(甲基-d3)吲哚-3-基)]嘧啶-2-基}-5-硝基苯-1,4-二胺(4); 4经还原反应后,与氯丙酰氯发生缩合反应合成了氘代AZD9291,总收率8.5%,其结构经1H NMR, 13C NMR和ESI-MS表征。  相似文献   

13.
N-(Pyren-1-ylmethyl)-(3R,4R)-4-(hydroxymethyl)pyrrolidin-3-ol was synthesised from (3R,4R)-4-(hydroxymethyl)pyrrolidin-3-ol and (3R,4S)-4-[(1S)-1,2-dihydroxyethyl] pyrrolidin-3-ol using alkylation with 1-(chloromethyl)pyrene or reductive amination with pyrene-1-carbaldehyde and NaCNBH3. The incorporation of N-(pyren-1-ylmethyl)azasugar moiety into oligodeoxynucleotides (ODN) as a bulge to form an intercalating nucleic acid (INA) induced a slight destabilization of INA-DNA duplex, whereas the INA-RNA duplex was strongly destabilized and 9 degrees C difference per modification in thermal stability between INA-DNA over INA-RNA duplexes was observed. The stabilization of a DNA three way junction (TWJ) was improved when the intercalator moiety was inserted into the junction region as a bulge.  相似文献   

14.
Phytochemical investigations from the roots of Cynanchum stauntonii led to obtain four new C_(21) steroidal glycosides(1–4) and one known compound stauntoside F(5). Their chemical structures were characterized by sophisticated analyses of IR, HRESI-TOF-MS, 1D, and 2D-NMR data, together with chemical methods, which showed interesting 13,14:14,15-disecopregnane-type skeleton or 14,15-secopregnane-type skeleton C_(21) steroidal glycosides. Among them, compound 1 was determined to be glaucogenin C 3-O-b-D-glucopyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-thevetopyranoside. Compound 2 was characterized to be hirundigenin 3-O-a-L-diginopyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-30-demethyl-thevetopyranoside. Compound 3 was identified to be(14S,16 S,20R)-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-oleandropyranoside.Compound 4 was identified to be(14S,16 S,20R)-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-Dthevetopyranoside. Among them, compound 2 was hirundigenin type C21 steroidal glycoside that existed in nature as epimers due to the presence of 14-hemiketal hydroxyl group in its structure. In addition, the anti-inflammatory and cardiomyocyte protective effects of compounds 1–4 were evaluated. We found that they exhibited significant protective effects on hypoxia/reoxygenation induced cardiomyocyte injury, but did not showed obvious anti-inflammatory function.  相似文献   

15.
(1→4)-α- and (1→4)-β-D-linked glucosidic oligosaccharide chains were generated by the Monte Carlo method, and the scattering from the systems composed of simulated chains was calculated to compare with the results of small-angle X-ray scattering from the oligosaccharides in aqueous solution. By extending the simulation to a longer chain, a single chain conformation of (1→4)-α- and (1→4)-β-D-linked polysaccharides was evaluated. On the basis of the simulation, the suprastructure of (1→4)-α- and (1→4)-β-D-linked polysaccharides and their gel formation mechanism were discussed in some detail by analyzing the small-angle X-ray scattering from the aqueous solutions of (1→4)-α- and (1→4)-β-D-linked polysaccharides.  相似文献   

16.
枸杞子糖缀合物LbGp4糖链的结构及其免疫活性的研究   总被引:3,自引:0,他引:3  
枸杞子糖缀合物LbGp4经β--消除、柱层析分离后得到一条分子量高达180800的分支多糖化合物LbGp4-OL.LbGp4-OL糖基组成为n(Rha):n(Ara):n(Gal)=0.05:1.33:1.根据甲基化、部分酸水解及1HNMR、13CNMR分析,确定了其主要的结构,并对LbGp4和LbGp4-OL的免疫活性进行了研究.  相似文献   

17.
微波辐射下2-[4-二-(4-氟苯)甲基]哌嗪乙酰腙化合物的合成   总被引:3,自引:0,他引:3  
李清寒  赵志刚 《有机化学》2009,29(1):119-122
微波辐射条件下, 以丙酮作溶剂, 1-[二-(4-氟苯)甲基]哌嗪与氯乙酸乙酯反应得到2-[二-(4-氟苯)甲基]哌嗪乙酸乙酯(1), 1与水合肼在微波辐射条件下反应得到2-[二-(4-氟苯)甲基]哌嗪乙酰肼(2), 进一步在微波辐射条件下由2-[二- (4-氟苯)甲基]哌嗪乙酰肼(2)与取代芳香醛反应制得目标化合物3a~3f. 合成的6个目标化合物通过熔点测定和质谱、红外光谱、核磁共振氢谱分析、元素分析对其结构进行确证.  相似文献   

18.
Poly(aryl ether ketone)s are a category of high performance engineering thermoplastics characterized by high glass transition temperature and excellent thermooxidative stability. And they have important applications in electronic, electric, aircraft and aerospace industries1~3. Considerable efforts have been made towards the improvement of solubility or processability of poly(aryl ether ketone)s4,5. In our work, a novel bis(phthalazinone) monomer 1 4, 4-biphenyl-bis[4-phthalazin-1(2H)-one] …  相似文献   

19.
Soluble aromatic polyamides containing phthalazinone moieties were prepared. Those polymers were obtained from the solution polymerization of a new diacid containing phthalazinone moieties with various diamines. The new monomer, 2-(4-carboxyphenyl)-4-(4-carboxyphenoxy)phenyl-1(2H)phthalazinone(Ⅳ) was synthesized in a two-step reaction sequence. 2-(4-Cyanophenyl)-4-(4-cyanophenoxy)phenyl-1(2H)phthalazinone (Ⅲ) was prepared via the condensation reaction of 4-(4-hydroxyphenyl)-1(2H)phthalazinone (Ⅰ) with p-chlorobenzonitrile (Ⅱ). After (Ⅲ) was hydrolyzed, (Ⅳ) was acquired. The synthesized polyamides were characterized by means of viscosimetry, DSC, FT-IR, 1H NMR and EA. The polyamides have a high glass transition temperature which can be as high as 316 ℃. The polyamides also have good solubilities in some organic solvents.  相似文献   

20.
付桂云  魏梅红  盛寿日  姜建文 《应用化学》2010,27(12):1478-1480
在碘化亚铜、四丁基溴化铵和磷酸钾存在下,9,9-二(4-羟基苯基)呫吨(1)和4-甲基碘苯(2)于N,N-二甲基甲酰胺溶剂中发生Ullmann偶联反应,加热回流反应24 h,以95%的产率合成了中间体--9,9-二[4-(4-甲基苯氧基)苯基]呫吨(3),继而加入催化量的N-溴代丁二酰亚胺并在光照条件下,将中间体3氧化得到一种新型芳香族二羧酸--9,9-二[4-(4-羧基苯氧基)苯基]呫吨(4),其产率为84%,二步反应总收率为79.8%。 目标化合物4经1H NMR、13C NMR、IR和元素分析测试技术确定了其结构。 该法具有原料易得,操作简单,反应条件温和,收率高等优点。  相似文献   

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