共查询到19条相似文献,搜索用时 312 毫秒
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以8-羟基喹啉为原料,通过Reimer-Tiemann反应合成了5-甲酰基-8-羟基喹啉(收率15.0%)和7-甲酰基-8-羟基喹啉(收率21.5%),其结构经1HNMR和IR表征。 相似文献
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以2,4,6-三羟基苯乙酮和2,6-二羟基苯乙酮为原料, 分别通过甲基保护酚羟基、 苯甲酰氯酰化、 Bake-Venkataraman重排、 异戊烯基化、 酸催化关环及EtSLi脱去甲基等6步反应, 以高收率完成了天然5,7-二羟基-3-异戊烯基黄酮(1a, 收率80.6%)和5-羟基-3-异戊烯基黄酮(1b, 收率84.9%)的全合成, 所有化合物均经 1H NMR 和 13C NMR表征确定. 通过密度泛函理论方法对目标产物(1a和1b)的生物活性进行了预测. 结果表明, 3位异戊烯基侧链的存在能大大增强化合物相应的生物活性, 而且是化合物生物活性增强必需的取代基. 另外, 目标产物1a的生物活性高于产物1b, 归因于黄酮类化合物分子中A环上的7-OH属增效基团, 起到增强生物活性的作用, 化合物1a分子中A环上有7-OH, 而化合物1b分子中则无该基团. 本合成方法对其它3-烃基黄酮类天然化合物的合成具有潜在的适用性, 所预测的生物活性结果为3-烃基黄酮类化合物的构效关系研究奠定了基础. 相似文献
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以苯胺为原料,经重氮化、偶合、还原得到4-羟基-5-乙氧基苯胺。合成中,通过保险粉还原偶氮化合物的方法在芳香环上引进氨基,不仅产物收率高(总收率86%,较文献提高了26.3%),而且还原产物容易分离,粗品纯度可达95%。本合成路线中间体均不经提纯,且氨基的引入中避免了贵金属的加氢还原,是一条适合大规模生产4-羟基-5-乙氧基苯胺的新合成工艺路线。 相似文献
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以2,4-二羟基二苯甲酮、4-羟基苯乙酮(HAP)为原料分别和环氧氯丙烷反应,经微波辐照合成了两种反应性紫外线吸收剂2-羟基-4-缩水甘油醚基二苯甲酮(HEPBP)和4-缩水甘油醚基苯乙酮(EPAP)。结构采用红外光谱、核磁和质谱表征。最佳合成条件为:n(羟基芳香酮)∶n(环氧氯丙烷)=1∶3,微波功率400W,于90℃反应15min,收率分别是52.6%和58.3%。与常规合成方法比较,微波合成法能降低反应温度、大大地缩短反应时间。产物中环氧丙烷基团的引入能明显改善芳香酮类紫外线吸收剂的紫外吸收性能。 相似文献
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以商业化易得的具有碱性氮原子的手性药物为有机催化剂,用于催化β-酮酸酯不对称α-羟基化反应,发现以噻吗洛尔或普萘洛尔为催化剂,反应对映选择性分别可达32%和18%.对噻吗洛尔和普萘洛尔进行结构修饰,合成了12个洛尔药物类似物,并考察了其催化效果,发现在优化的反应条件下,以30mol%(R)-1-叔丁胺基-3-(2-萘氧基)-2-丙醇(7f)为催化剂,20mol%β-环糊精为助催化剂,叔丁基过氧化氢为氧化剂,正己烷为溶剂,反应对映选择性最高可达57%,收率92%.不对称α-羟基化产物(S)-5-氯-2-羟基-1-茚酮-2-甲酸甲酯(2a)在乙酸乙酯中一次重结晶后,对映体光学纯度可达99%,收率68%. 相似文献
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Viviana Heguaburu Hugo do Carmo Florencia Parpal María Eugenia Amorós Andrés González 《Tetrahedron letters》2017,58(18):1738-1741
The synthesis of 3-hydroxy-2-hexanone and 2,3-hexanediol, two components of the aggregation pheromone of several cerambycid species, is disclosed in here. Starting from 2-hexanone, through an α-hydroxylation using (diacetoxyiodo)benzene, 3-hydroxy-2-hexanone is obtained in good yield. Further reduction of this compound, gives 2,3-hexanediol in excellent yield. A study of the α-hydroxylation reaction of several alkylketones using an hypervalent iodine reagent is also disclosed in here. The synthesis of optically active compounds (R)- and (S)-3-hydroxy-2-hexanone was achieved starting from 2-hexanone with nitrosobenzene and l- and d-proline respectively, in several reaction media. 相似文献
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Summary The synthesis of some 5-cyano-4-hydroxy-2-pyridone derivatives (3 a–c) by condensation of 3-aminocrotononitrile (1) with substituted diethylmalonates (2 a–c) is described. Reaction of3 a with phosphorus oxychloride yields 4,6-dichloro-3-pyridinecarbonitrile (7 a), which reacts with various nucleophiles to give substituted 3-pyridinecarbonitriles (8–10).See ref. [1] 相似文献
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报道了2-氨基-6-氟-9-(4-羟基-3-羟甲基丁基)嘌呤(1)的合成, 通过对起始原料2-氨基-6-氯-9-(4-乙酰氧基-3-乙酰氧甲基丁基)嘌呤(2)水解脱去乙酰基, 得到2-氨基-6-氯-9-(4-羟基-3-羟甲基丁基)嘌呤(3). 化合物3与三甲胺乙醇溶液在混合溶剂[V(THF)∶V(DMF)=3∶1]中反应得到相应的氯化铵盐4, 然后与KF在DMF溶剂中反应, 得到化合物1. 产品经UV-vis, IR, 1H NMR, 19F NMR和MS表征. 考察了反应温度、氟化试剂等因素对氟化反应的影响, 为6位含氟的嘌呤核苷类化合物的合成提供了一种直接、简易的新方法. 相似文献
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Shuyin Liu Guihua Xiong Fengxi Li Shushu Wei Zhi Wang 《Green Chemistry Letters and Reviews》2016,9(4):190-195
(S)-3-hydroxy-3-(2-thienyl) propanenitrile, which is the key chiral building block for the synthesis of (S)-duloxetine, was successfully prepared via enantioselective transesterification catalyzed by lipase under ultrasound irradiation. Compared with conventional shaking, the enzyme activity and enantioselectivity were dramatically enhanced under ultrasound irradiation. Under optimum reaction conditions (solvent: n-hexane, ultrasound power: 150?W, aw: 0.33, temperature: 40°C), Pseudomonas sp. lipase exhibited an excellent catalytic performance (enzyme activity: 81.5?μmol?g?1?min?1, E-value: 65.4). The reaction achieved its equilibrium in approximately 7?h with a conversion of 53.9% and high enantiopurity (99% ee) of (S)-3-hydroxy-3-(2-thienyl) propanenitrile could be obtained. 相似文献
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An efficient synthetic route to muurolane type sesquiterpenes starting from (R)-carvone, employing allylic diazene rearrangement and the ring closing methesis (RCM) reaction as key steps, is described. The first asymmetric total synthesis of (-)-10α- hydroxy-4-muurolen-3-one 11 and (-)-10β-hydroxy-4-muurolen-3-one C was accomplished. Through the total synthesis, the absolute configurations of the natural products A, B and C were established. 相似文献
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A convenient large scale synthesis of 2-hydroxy-3-pinanone from readily available α-pinene has been developed. This two step method involves the diastereoselective dihydroxylation of α-pinene and subsequent oxidation of pinanediol to the hydroxyketone. The key advantages of this method, which allows access to large quantities of this important chiral auxiliary, are high yield and ease of operation. 相似文献
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A synthesis of methyl 2-hydroxy-4-oxo-4-(substituted phenyl)butanoates has been accomplished using Friedel-Crafts acylation of substituted benzenes with 2-acetoxybutanoyl chloride.The key feature of this strategy is that various 4-arylbutanoates can be obtained conveniently,which are important intermediates for the synthesis of biologically active compounds including ACE inhibitors. 相似文献
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Bade Thirupaiah 《合成通讯》2014,44(4):513-519
A one-pot procedure has been developed for the synthesis of substituted 2,3-dihydro-2-(6-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7H-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazin-3-yl)phthalazine-1,4-diones by reaction of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and phthalic anhydrides in acetic acid medium. Similarly, a one-pot, three-component synthetic procedure has been developed for substituted 3-[3-(N1-benzylidene-hydrazino)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-4-hydroxy-6-methyl-pyran-2-ones from 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and various aromatic aldehydes in absolute ethanol and a few drops of glacial acetic acid.
[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献