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1.
梁达文 《化学通报》1995,(12):26-27
柱色谱分离纯化茉莉醛梁达文(广西玉林高等师范专科学校化学系玉林537000)茉莉醛是一种广泛用于洗涤剂、化妆品和食品的重要香料 ̄[1-4]。利用苯甲醛与庚醛在碱性条件下合成的茉莉醛,其主要副产物庚醛自缩物(2-正戊基-2-壬烯醛)对茉莉醛的香气质量影...  相似文献   

2.
为合成某些芳香族有机化合物提供一种新途径,用色谱-质谱联用技术和质量色谱法研究了苯甲酸钐的热分解反应产物。其热分解产物溶入丙酮后有大量9,10-蒽醌析出,其丙酮溶液中还含有1,2-二苯甲酰基苯(25.6%)、苯甲酸(18.7%)、二苯酮(14.4%)、9-勿酮(8.2%)、9-苯甲勿(4.9%)、取苯(3.6%)、二苯甲烷(2.3%)、3-甲酰苯基联苯(2.1%)、二苯基乙二酮(1.9%)、4-甲  相似文献   

3.
用低价钛试剂(TiCl4-Zn)与3-氧代-1-(3′,4′-亚甲二氧苯基)-3-苯基丙基-1-丙二腈反应合成了非对映消旋体(1S,4R;1R,4S)和(1S,4S:1R,4R)2-氨基-3-氰基-1-苯基-4(3-4-亚甲二氧苯基)-2-环戊烯-1-醇,用X射线衍射分析确定了这两个异构体的相对构型。  相似文献   

4.
4,4'-偶氮二[4-氰基戊酰(对-二甲氨基)苯胺]作为引发剂的嵌段共聚物合成邱醒宇,魏峰,关宏宇,平学真(辽宁大学化学系,沈阳,110036)关键词4,4'-偶氮二[4-氰基戊酰(对-二甲氨基)苯胺],多官能团引发剂,自由基聚合70年代以来,陆续报...  相似文献   

5.
李慧义  罗淑荣 《色谱》1995,13(4):277-278
在高效硅胶薄层板上分离了牛蒡子中4种2,3-苄基丁内酯型木脂素──牛蒡甙元(I)、牛蒡素B(Ⅱ)、牛蒡酚A(Ⅲ)、牛蒡酚F(Ⅳ)。流动相为二氯甲烷-乙醚-甲醇-己烷(4:1:0.4:1),室温放置,自然显色。薄层扫描法定量,各木脂素的线性范围在0.451~4.608μg,回收率为99.90%~100.90%,并用此法测定了不同产地牛蒡子中木脂素的含量。方法简便、快速,样品用量少。  相似文献   

6.
含联苯核和取代基液晶聚甲亚胺醚的合成张其震,薛庆斌,李小放(山东大学化学系,济南,250100)关键词聚甲亚胺醚,相转移催化,双-(3-甲氧基-4-羟基苄叉)-4,4’-二亚胺基联苯,条带织构高分子液晶中聚酷胺和聚酯研究较多,聚甲亚胺醚研究较少,Wo...  相似文献   

7.
以1-甲基-3-乙基(4-氯)-5-哟唑甲作原料,经两步得到4-氨基-3-(1-甲基-3-乙基(4-氯)-5-吡唑基)-1,2,4-三唑-5-硫酮(3),3再与取代酸反应,得到一系列3(1-甲基-3-,乙基(-4-氯)-5-吡唑基)-6-取代均三并「3,4-b」-1,3,4-噻二唑(4,5,6),元素分析、HNMR、IR和MS确定了它们的结构,初步生侧结果表明,3具有植物生长调节活性,4b、4d、  相似文献   

8.
合成和表征了4种以四溴代邻苯二甲酸根阴离子(4Br-PHTH)桥联、以1,10-菲咯啉(phen),5-硝基-1,10-菲咯啉(NO_2-phen),2,2′-联吡啶(bpy)和4,4′-二甲基-2,2′-联吡啶(Me_2bpy)端接的双核钴(Ⅱ)配合物[Co_2(4Br-PHTH)(L)_4](ClO_4)(L=phen(l),NO_2-phen(2),bpy(3),Me_2bpy(4))。基于IR光谱、元素分析、电导测量等方法推定配合物具有四溴代邻苯二甲酸根桥联结构和Co(Ⅱ)离子具有畸变的八面体配位环境。进行了配合物变温磁化率(75~300K)的测定,其数据已用从自旋哈密顿符导出的磁方程拟合,求得交换参数J=-0.87cm~(-1)(1),-0.84cm~(-1)(2),-0.82cm~(-1)(3),-0.85cm~(-1)(4),表明金属离子间有弱的反铁磁性自旋交换相互作用。  相似文献   

9.
通过3-苄基-4-芳酰基-1,2,4-三唑-5-巯基负离子在2-甲磺酰基-5-苯基-1,3,4-E二唑环2-位上的亲核取代反应,制得13个新的(3-苄基-4-芳酰基-1,2,4-三唑-5-基)(5-苯基-1,3,4-E二唑-2-基)硫醚衍生物。经元素分析、IR、^1H NMR和MS裂解碎片分析确认结构。初步观察了它们在0.01%浓度时对大肠杆菌繁殖的抑制作用。  相似文献   

10.
刘波  朱有瑜 《分析化学》1995,23(8):945-948
合成了新试剂2-[2'-(4'-甲基-苯并噻唑)偶氮]-5-二甲氨基苯甲酸,并研究了其与钯(Ⅱ)的显色反应。实验表明,在50%乙醇介质中,该试剂与钯(Ⅱ)反应生成1:1络合物,其最大吸收波长为698nm,表观摩尔吸光系数为5.83×10^4L.mol^-1.cm^-1。  相似文献   

11.
N-(Ferrocenylmethyl)imidazole (3a), 1-(ferrocenylmethyl)-1,2,4-triazole (3b), 1,1'-bis[(1H-imidazol-1-yl)methyl]ferrocene (8a), 1,1'-bis([1H-(2-methyl)imidazol-1-yl]methyl]ferrocene (8b), and 1,1'-bis[(1H-1,2,4-triazol-1-yl)methyl]ferrocene (8c) were synthesized in moderate yields. These compounds were quaternized with methyl iodide to form 1-(ferrocenylmethyl)-3-methylimidazolium iodide (4a), 1-(ferrocenylmethyl)-4-methyl-1,2,4-triazolium iodide (4b), 1,1'-bis([1-(2,3-dimethyl)imidazolium]methyl)ferrocene diiodide (9b), and 1,1'-bis([1-(4-methyl)-1,2,4-triazolium]methyl)ferrocene diiodide (9c), respectively, in excellent yields. Compounds 4a, 4b, 9b, and 9c were metathesized with bis(trifluoromethanesulfonyl)amide to give high yields of 5a, 5b, 10b, and 10c. With potassium hexafluorophosphate, 9b forms 10d. Salts 5a, 5b, and 10c are the first room-temperature ionic liquids with cations containing an organometallic moiety that exhibit T(g) values well below room temperature, i.e., -32, -16, and -11 degrees C. The compounds were characterized by (1)H, (19)F, and (13)C NMR, MS, and elemental analyses. T(g) values and melting points were determined by DSC. T(d) values (5% weight loss temperature) were recorded by TGA. X-ray single-crystal structures show that 9c and 10d crystallize in the triclinic space group P.  相似文献   

12.
Terminalia catappa L. (tropical almond) is a nutritious fruit found mainly in the tropics. This study is aimed to establish the naturally biotransformed molecules and identify the probiotic agents facilitating the fermentation. The aqueous extracts from both the unfermented and fermented T. catappa nuts were subjected to gas chromatography/mass spectrometry (GC/MS) analysis. Syringol (6.03%), glutamine (1.71%), methyl laurate (1.79%), methyl palmitate (1.53%), palmitic acid (5.20%), palmitoleic acid (2.80%), and methyl oleate (2.97%) were detected in the unfermented nuts of the T. catappa. Additionally, two of these natural compounds (palmitic acid (4.19%) and palmitoleic acid (1.48%)) survived the fermentation process to emerge in the fermented seeds. The other natural compounds were biotransformed into 2,3-butanediol (1.81%), butyric acid (16.20%), propane-1,3-diol (19.66%), neoheptanol (2.89%), 2-piperidinone (6.63%), palmitoleic acid (1.18%), formamide, n-(p-hydroxyphenethyl)- (2.80%), and cis-vaccenic acid (1.69%) that newly emerged in the fermented seeds. The phytochemical compounds are likely carbon sources for the organisms facilitating the biotransformed molecules and product production. Four (4) potential probiotic bacteria strains, namely, Probt B1a, Probt B2a, Probt B4a, and Probt B4b, were isolated from the fermented nut. Enterococcus faecum, and Enterococcus faecalis were the organisms identified as driving the fermentation of the seeds. All strains were gram-positive, catalase-negative, and non-hemolytic, which suggests their harmless nature. N-(p-hydroxyphenethyl)-) was associated with fermentation for the first time, and neoheptanol was discovered as the main alcoholic molecule formed during the fermentation of the seeds. This fermentation is a handy tool for bio-transforming compounds in raw food sources into compounds with nutritious and therapeutic potentials.  相似文献   

13.
Four new aromatic allenic ethers, (7E)-3-(4-buta-2,3-dienyloxy-3-methoxy-phenyl)-acrylic acid methyl ester (1), (7E)-3-[4-(4-buta-2,3-dienyloxy-benzyloxy)-phenyl]-acrylic acid methyl ester (2), 4-(4-buta-2,3-dienyloxy-benzyloxy)-benzoic acid methyl ester (3), (7E)-3-[4-(4-buta-2,3- dienyloxy-benzyloxy)-3-methoxy-phenyl]-acrylic acid methyl ester (4) were isolated from the fungus Xylaria sp. No. 2508. The structures of those compounds were determined by analysis of spectroscopic data, mainly 2D NMR experiments.  相似文献   

14.
4-Amino-5-(pyridin-3-yl)-4H-l,2,4-triazole-3-thiol 1 were condensed with 2-bromo-l-(substituted phenyl)ethanone to give pyridinyltriazolothiadiazines 2a-c, which were quaternarized with methyl iodide and oxidized with 30 % hydrogen peroxide to afford the corresponding methyl pyridinium salts 3a-c and pyridine- 1 -oxides 4a-c, respectively. The redtiction of compounds 3 and 4 with NaBH4 in methanol produced the target compounds 1-methyl- 1.2.5.6-tetrahydropyridin-3-yl)-6-aryl-s-triazolothiadiazines 5a-c and 3-( l-hydroxyl- 1, 2, 5, 6-tetrahydropyridin -3-yl)-6-aryl-s-triazolothiadiazines 6a-c, respectively. The endothelium vascular relaxing activity of the target compounds was screened.  相似文献   

15.
Many 2-[[(4-fluoroalkoxy-2-pyridyl)methyl]sulfinyl]-1H-benzimidazoles were synthesized and tested for anti-secretory, antiulcer, and cytoprotective activities. Most of these compounds were superior to omeprazole in anti-secretory and antiulcer potencies, and especially in protecting the gastric mucosa from ethanol-induced damage. Among these compounds, 2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridyl]methyl]sulfinyl] - 1H-benzimidazole, AG-1749 (lansoprazole) (6f), was selected for further development and clinical evaluation.  相似文献   

16.
The flowers and leaves of Trifolium repens L. (Fabaceae) were subjected to phytochemical investigation in order to identify their major chemical constituents and to evaluate in?vitro antioxidant activity of the isolated compounds against DPPH˙. A total of 12 flavonoids, pterocarpan and methyl caffeate were isolated, then characterised by UV, MS, NMR spectroscopy and identified as quercetin and kaempferol 3-O-(6″-α-rhamnopyranosyl-2″-β-xylopyranosyl)-β-galactopyranosides (1, 2), kaempferol 3-O-(2″,6″-α-dirhamnopyranosyl)-β-galactopyranoside, mauritianin (3), quercetin and kaempferol 3-O-(2″-β-xylopyranosyl)-β-galactopyranosides (4, 5), kaempferol and quercetin 3-O-β-(6″-O-acetyl)-galactopyranosides (6, 7), trifolin (8), hyperoside (9), myricetin 3-O-β-galactopyranoside (10), quercetin (11), ononin (12), medicarpin 3-O-β-glucopyranoside (13) and methyl caffeate (14). Mauritianin, ononin, pterocarpan and methyl caffeate have been reported in this plant for the first time. The compounds 4, 7, 9, 10, and 11 were tested for their antioxidant effect against DPPH˙. All studied compounds were found to have potent activity, but the most effective in the test were compounds 9, 10 and 11 (EC(50) values in the range 7.51-9.52?μM).  相似文献   

17.
A new diphenyl ether methyl 2-(2-formyl-3-hydroxy-5-methylphenoxy)-5-hydroxy-3-methoxybenzoate (3), together with four known compounds, asterric acid (1), methyl asterrate (2), 9(Z),12(Z)-nonadecadienoic acid (4) and orsellinic acid (5), were isolated from the Phoma sp. strain SHZK-2, which was isolated from a polluted environment in southern China. The structures of these compounds were determined by spectroscopic methods. Cytotoxicities of compounds against HEPG2 cell and Raji cell lines were preliminarily evaluated by the MTT method.  相似文献   

18.
Crystal structures have been determined of methyl trans-1-hydroxy-6-nitro-3-oxobicyclo[4.4.0]decane-2-carboxylate ( 19 ), cis-3-methyl-6-nitro-2-oxabicyclo[4.4.0]decan-1-ol ( 2 ), cis-7-hydroxy-1-nitrobicyclo[5.4.0]undecan-9-one ( 13 ), and the medium-ring compounds 2-acetyl-4-nitrocyclooctanone ( 9 ), methyl 5-nitro-2-oxocyclooctane-carboxylate ( 4 ), 2-acetyl-4-nitrocyclononanone ( 11 ), 2-acetyl-4-nitrocyclodecanone ( 15 ), benzyl 5-nitro-2,11-dioxocycloundecanecarboxylate ( 24 ), methyl 5-nitro-2,12-dioxocyclododecanecarboxylate ( 21 ), and 8-nitro-11-oxo-13-tridecanolide ( 7 ), which are intermediates, side products, or end products of the ‘Zip’ ring-enlargement reaction. The conformations of most of the medium-ring compounds are very similar to equal-sized ring compounds previously determine by other authors.  相似文献   

19.
The methanol extract of the seeds of Phytolacca americana was reinvestigated to yield three new 1,4-benzodioxane-type compounds, americanoic acid methyl ester (1), isoamericanoic acid A methyl ester (2), and 9'-O-methylamericanol A (3) along with the previously isolated neolignans 6-9. The structures of 1-3 were characterized by 2D NMR and long-range selective proton-decoupling (LSPD) techniques. The neuritogenic effects of compounds 1-3, and dicarboxilic acids 4 and 5, which had been previously synthesized with horseradish peroxidase-catalyzed oxidative coupling of caffeic acid, were examined in primary cultured rat cortical neurons. Americanoic acid A methyl ester (1) exhibited neurite outgrowth-promoting activity at concentration of 0.01-1.0 microM, whereas dicarboxilic acids 4 and 5 were found to induce neuritogenesis dose dependently at the concentrations from 0.1 microM to 10 microM.  相似文献   

20.
The metabolites of 1-[bis(4-fluorophenyl)methyl]-4-(2,3,4-trimethoxybenzyl)piperazine dihydrochloride (KB-2796, 1), a cerebral vasodilator, and related compounds were synthesized to confirm the proposed structures. The structures of the metabolites (3-5) in rats were identified by means of synthesis of the authentic compounds.  相似文献   

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