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以生物质来源的对甲氧基苯甲醛(大茴香醛)为原料,经还原反应制备得到对甲氧基苄醇,经氯代反应制备得到对甲氧基氯苄,再与乙酰乙酸乙酯经取代反应制备得到2-乙酰基-3-(4-甲氧基苯基)丙酸乙酯,再经串联的水解、脱羧反应制备得到4-(4-甲氧基苯基)-2-丁酮,最后经脱甲基反应制备得到4-对羟基苯基-2-丁酮,总收率为60.7%。具有路线简捷、易于操作、环境友好、收率高等优点。 相似文献
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黄酮类化合物研究(Ⅷ)——7-取代黄酮及2'''',4-二羟基-3-甲氧基-4''''-取代查尔酮的合成 总被引:1,自引:0,他引:1
3,4′,7-三羟基黄酮和3,3′,4′,7-四羟基黄酮是中草药舒冠通糖浆的主要成份,该药对冠心病、心绞痛、胸闷有一定疗效。为系统研究黄酮类化合物的构效关系,我们在前文基础上又合成了5个新的4′-羟基-7-取代黄酮及5个3′-甲氧基-4′-羟基-7-取代黄酮。在此过程中,又合成了4个新的2′,4-二羟基-3-甲氧基-4′-取代查尔酮。其合成路线如下: 相似文献
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最近,7α-羟基-DHEA已经作为在人的脂肪基质细胞的作用下DHEA代谢的主要产物分离出来[1],并且在人的前列腺组织中也发现了3-β甾体的7-羟基化反应.在活体内将标记的5α-雄甾-3β,17β-二醇注射到人体内结果可以在尿内发现7-羟基化代谢物[2].研究表明7-羟基化的甾体可以提高老鼠的免疫能力,也具有抗糖(肾上腺)皮质激素的作用[3].DHEA在用Fusarium sp.进行生物转化时得到的产物是7α-羟基衍生物,在用Rhizopus sp.进行反应时得到的是7α-OH-DHEA,7β-OH-DHEA和3β-羟基-5-雄甾,7,17-二酮的混合物.Culmorum对5-烯类甾体的羟基化反应主要发生在7α位.Morfin等研究了Fusarium moniliform的DHEA诱导7α-羟基化酶对具有重要的药理作用的3-羟基甾体的转化性,DHEA几乎全部被7α-羟基化,而PREG,EPIA和ESTR只是部分地转化成其7α-羟基衍生物,因而也发生了其它未定位置上的羟基化反应以及将C-17或C-20上羰基还原成醇,这种酶不能转化胆甾醇. 相似文献
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通过5-甲基-7-甲氧基异黄酮与盐酸羟胺的缩合制得中间产物4-苯基-5-(2-羟基-4-甲氧基-6-甲基苯基)异恶唑,然后经过光异构化反应合成了4-甲氧基-6-甲基-7a-苯基苯并吡喃并[2,3-b]氮丙啶-7-酮,并采用IR,NMR,HRMS和单晶X-衍射分析对其结构进行了表征.单晶X-衍射分析结果表明:标题化合物属于单斜晶系,空间群P2(1)/n.在其晶体结构中,存在着氢键及芳香堆积作用,这些作用将标题化合物分子组装成了三维网络结构. 相似文献
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在DMSO/I2的氧化作用下,由2′,4′-二氢-6′-甲氧基-3′,5′-二甲基查耳酮可合成一种全新结构的黄酮:7-羟基-5-甲氧基-6,8-二甲基黄酮(产率91%),而在HCl/MeOH作用下则得到了两种黄烷酮:7-羟基-5-甲氧基-6,8-二甲基黄烷酮(产率70%)和5,7-二羟基-6,8-二甲基黄烷酮(产率20%)。 相似文献
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新显色剂二甲氧基羟基苯基荧光酮光度法测定钼的研究 总被引:3,自引:0,他引:3
在表面活性剂存在下,利用2,3,7-三羟基荧光酮类试剂与钼形成配合物的显色反应灵敏度较高,选择性较好,因此该类试剂是光度法测定钼的一类重要显色剂。目前已报道有水杨基荧光酮、苯基荧光酮、二溴苯基荧光酮、二溴羟基苯基荧光酮、邻羟基萘基荧光酮等。为进一步研究这类试剂并提高其分析性能,本文合成了荧光酮试剂——二甲氧基羟基苯基荧光酮(DMH-PF),学名是2,3,7-三羟基-9-(3,5-二甲氧基-4-羟基)苯基荧光酮,其结构式为 相似文献
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以胆固醇为原料,经酰化、氧化、还原、水解以及消除等5步反应合成维生素D3原7-脱氢胆固醇,总收率42%,其结构经1H NMR和13C NMR确证。研究了酰化反应、氧化反应、还原反应和消除反应条件对收率的影响。 相似文献
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M. S. Frasinyuk A. V. Turov V. I. Vinogradova V. P. Khilya 《Chemistry of Natural Compounds》2007,43(3):285-290
8-Aminomethyl derivatives of 7-hydroxychromones were prepared by reaction of methylene-bis-cytisine with substituted 7-hydroxychromones.
The structures of the synthesized compounds were investigated using NMR spectroscopy.
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Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 237–241, May–June, 2007. 相似文献
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Tadanobu Sawada Hiroyuki Ishii Yoshitomo Aoyama Toyotoshi Ueda Junji Aoki Minoru Takekawa 《合成通讯》2013,43(6):784-793
7H-Naphtho[1,8-gh]quinolin-7-one was prepared by the glycerol condensation of 3-aminophenalenone in good yields. This method provides a new and convenient synthesis of the compound. NMR spectra of its related compounds were measured, and the rapid interchange between two equivalent α-enone structures was found, which is well known as the phenomenon for the formation of carboxylic acid dimer or hydrogen difluoride ion. 相似文献
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Min Jung Lee Nirmal K. Shee Jung-In Son Subramanian Karthikeyan Kwang-Hwan Jhee 《Supramolecular chemistry》2019,31(6):369-376
Supramolecular complexation of two bio-thiols, homocysteine (Hcys) and cysteine (Cys), by cucurbit[7]uril (CB[7]) has been fully investigated by 1H NMR spectroscopy, mass spectrometry, isothermal titration calorimetry, and the results were further verified with computational investigations. NMR titration experimental results obviously indicate that the binding stoichiometry of CB[7] to Hcys is 1:1 and to Cys is 1:2 in aqueous solution. The binding constants and thermodynamic parameters associated with the complexation between CB[7] and the bio-thiols were determined by isothermal titration calorimetry. The energy-minimized structures of the supramolecular complexes of CB[7] with Hcys and Cys were determined and provide good agreement with the experimental results. The CB[7] cavity is sufficient to include the two Cys, but is unable to accommodate two Hcys due to steric hindrance. The differing binding abilities of Hcys and Cys in aqueous solution towards CB[7] host may lead to discriminate them. 相似文献
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1INTRODUCTION Puerarin(4?,7-dihydroxy-8-β-D-glucosylisoflavo ne),whose chemical structure is shown in Fig.1,is a C-glycoside compound.It is present in a large amount of active components of Puerariae radix,a com-monly used Chinese herb,which exerts sedative and antipyretic actions and is often used to treat influ-enza,wrist stiffness and headache[1].A number of investigations were carried out internationally to iden-tify the physiological activities of puerarin such as antiproliferative… 相似文献
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LI Yu-feng BU Qing-min QIAN Yi PAN Yi LI Jian-xin HUANG Le-qun ZHU Hong-jun . School of Science Nanjing University of Technology Nanjing P. R. China 《高等学校化学研究》2008,24(5):557-560
Several borohydride reagents: sodium borohydride, sodium cyanoborohydride, soudium acetoxyborohydride and soudium triacetoxyborohydride were screened, respectively, for the reduction of 7-demethylsinomenine, which was an α,β-dicarbonyl compound derived from sinomenine. Highly regio-and stereo-selectivity was acquired when sodium cyanoborohydride or NaBH(OAc)3 was used. The product was structurally confirmed as 7R configuration by NMR, X-ray crystal diffraction analysis. Some preliminary discussion was also made on the mechanism of the selective reduction. 相似文献
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A series of novel 7′-azaindirubin (1a-g) and 7-azaindirubin (2a, 2c, 2e and 2f) derivatives were designed and synthesized. Their structures were characterized by 1H NMR and MS spectroscopy as well as by elemental analysis. Their inhibitory properties against CDK2/cylinA were evaluated in vitro. In contrast to indirubin, some of the described azaindirubins emerged as potent inhibitors of CDK2/cylinA and compound 2b had more potent activity. Biological tests also showed that nitrogen atom at 7-position of azaindirubin was more beneficial to enhance the kinase inhibitory activity. 相似文献