质体醌类似物的合成研究I.不同侧链的质体醌类似物

本文通过对2,3-二甲基-1,4苯醌与脂肪酸在过硫酸铵及硝酸银作用下发生自由基烷基化反应,合成了九种新的具有不同长短测链的质体醌类似物.其结构已经IR,UV,^1H NMR和MS证实.     

质体醌类化合物的合成研究

醌环的取代基对醌类化合物进行光合作用的电子传递过程有很大影响. 我们设想若能在保持与醌环上的甲基相近体积的条件下, 将其中一个甲基换成氯原子, 这样, 这类化合物醌环上的电子密度显然会低于质体醌, 从而进一步研究它们在光合作用中的作用, 有助于进一步阐明光合作用机制, 以3-氯-2-甲基苯胺为原料, 经氧化, 自由烷基化反应, 合成了十六个具有不同长侧链结构的质体醌类似物.     

库仑滴定剂醌

将氢醌在0.5-10N硫酸介质及鉑阳极上电解产生醌可以作为库仑滴定剂。氢醌氧化的电流-电极电势曲线说明电流效率易接近100%,实验也证明此点。用电生醌分别进行毫克量亚钛和二价钒的库仑滴定,误差为千分之几。用小型锌汞齐还原器可将四价或五价钒定量还原到二价,迅速方便。铬、鉬干扰钒的测定,而锰、钛不干扰。     

西地那非类似物的合成

报道了一种合成西地那非类似物的新方法。以邻丙氧基苯甲酸为原料,经5步反应制得西地那非类似物的关键中间体--硫代西地那非氯{1-甲基-3-丙基-5-(2-丙氧基-5-氯磺酰苯基)-1,6-二氢-7H-吡唑并［4,3-d］嘧啶-7-硫酮}(7); 7与哌嗪衍生物反应合成了4个新型的西地那非类似物,收率72.3%~80.9%,纯度99.0%,其结构经¹H NMR和ESI-MS表征。     

茉莉酮酸甲酯类似物的新方法

茉莉酮酸甲酯是茉莉花的主香成份。本文报道了另一类茉莉酮酸甲酯的类似物2-烃基-3-氧-环戊基-乙酸甲酯, 2-亚苄基-3-氧-环戊基-乙酸甲酯, 和2-(1-羟基-戊基)-3-氧-环戊基-乙酸甲酯, 及其合成的新方法。     

氯丙嗪裂环类似物的合成

对-氯苯基β-氯乙基硫醚与苯胺作用生成N-(β-对-氯苯硫乙基)-苯胺,而通过Gabriel合成法生成对-氯苯基β-氨乙基硫醚。此二化合物分别用β-氯丙酰氯酰化后再与各种仲胺缩合,各生成一系列的β-二烷氨基丙酰基衍生物。将这些化合物用氢化铝锂还原,得到一系列的γ-二烷氨基丙基衍生物(氯丙嗪的裂环类似物)。药理试验结果表明裂环后失去安神作用,但仍保留抗组织胺作用。其中尚有具很强局部麻醉作用者。对-氯苯基β-氯乙基硫醚、对-氯苯基β-氯乙基碸分别与各种仲胺作用,制成一系列对-氯苯基β-二烷氨基乙基硫醚和对-氯苯基β-二烷氨基乙基碸,其中有具抗组织胺作用者。     

鱼腥藻毒素类似物的合成研究

托品酮为原料经过八步和十步反应合成了一类新的双环生物碱, 3-甲氧羰基-4-甲基-9-氮杂双环[4.2.1]壬-3-烯和3-乙酰基-4-甲基-9-氮杂双环[4.2.1]壬-3-烯。合成的关键步骤是环烯醇磷酸酯与二甲基铜锂的加成-消除反应, 在低温下可以达到高的选择性, 脱N-甲基反应采用氯甲酸2, 2, 2-三氯乙基酯在温和条件下进行。     

新型氮蒽酮类似物的合成

以2-氯苯甲酸和1-氨基萘为原料制备了7-氯苯并吖啶(3);3分别与吗啉,N-甲基哌嗪,金刚烷胺,2,4-二甲基-6-巯基咪唑,N,N-二甲基乙二胺和5-氨基-3-巯基-1,2,4-三氮唑反应,合成了6个新型的氮蒽酮类似物,其结构经1H NMR和IR表征。     

醌型木素模型物的光学特性

为探索醌型木素化学结构与颜色的关系,以五种醌型木素模型物2-甲氧基-1,4-苯醌(I)、1,2-苯醌(II)、4-亚烯丙基-2-甲氧基-2,5-环己二烯酮(亚甲基醌)(III)、5-甲氧基-1,4-苯醌-2-氧负离子(IV)和5-甲基-1,4-苯醌-2-氧负离子(V)作为纸浆中醌型木素发色体的代表,在B3LYP/6-311++G(2d,p)水平上获得了它们在乙醇中的稳定基态构型,采用含时密度泛函理论(TD-DFT)在同等水平上计算了其在乙醇溶液中的电子光谱,并分析了它们在可见光范围内的吸收.结果发现:五种模型物在可见光范围内的吸收均源于电子的π→π*跃迁,它们的最大吸收波长顺序依次为IIIIIIIVV,吸光系数顺序依次为IVIVIIIII;漂白过程中生成的醌氧负离子以及邻醌类模型物具有中等大小的吸光系数(ε=1978-3197),吸收波长较长(445.47-552.36 nm),是漂白后纸浆具有颜色的重要原因.对醌类模型物吸收波长较小(414.91 nm),吸光系数大小为中等(ε=2094),亚甲基醌类模型物虽然吸光系数大(ε=31935),但吸收波长较小(407.90 nm),二者对漂白后纸浆的颜色影响较小.     

倍半萜EnglerinA及其类似物的合成

2008年从东非大戟科属植物Phyllanthus engleri 中分离的吉玛烷型倍半萜(-)-englerin A对6种肾脏癌细胞展示了非常好的抑制活性(GI₅₀:1-87nm),甚至比紫杉醇的抗癌活性高1-2个数量级。这类倍半萜因其结构特点和显著的抗癌活性引起了有机化学界的广泛关注, 短短几年之内,就有多条全合成路线先后被报道。本文主要综述了(-)-englerin A及其类似物的合成进展,按照各个研究小组运用的关键策略加以分类,来阐述他们各自的合成特点。     

Preparation of 2,3- and 2,5-dihydropyrazine 1,4-dioxides from 2-hydroxyamino-2-methylpropanal oxime and some of their properties

3-Hydroxy-2,3-dihydropyrazine 1,4-dioxide derivatives were obtained by condensation of 2-hydroxyamino-2-methylpropanal oxime with glyoxal, diacetyl, and 1,2-cyclohexanedione in water, and 3-methoxy-2,3-dihydropyrazine 1,4-dioxide was obtained by condensation with diacetyl in methanol. 2,5-Dihydropyrazine 1,4-dioxide is formed when 2-hydroxyamino-2-methylpropanal oxime is heated in a solution of acetone and dilute hydrochloridic acid. The reduction of 3-hydroxy- and 3-methoxy-2,3-dihydropyrazine 1,4-dioxides and 2,5-dihydropyrazine 1,4-dioxide leads to 1,4-dihydroxypiperazines, and the bromination of 3-methoxy-2,3-dihydropyrazine 1,4-dioxide gives 5,6-bis(bromomethyl)-3-methoxy-2,3-dihydropyrazine 1,4-dioxide. 1,4-Dihydroxy-2,5-piperazinedione was obtained by oxidation of 2,5-dihydropyrazine 1,4-dioxide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1414–1418, October, 1983.     

Head-to-head polymers. XV. A facile synthesis of 2,3-disubstituted succinates and butanediols-1,4

A synthetic approach that makes symmetrically 2,3-dialkyl-substituted succinates and compounds prepared from 2,3-dialkyl-substituted succinates easily available has been developed. Coupling of α-bromoalkanoic esters with a zinc/copper couple produced in about 40% yield 2,3-disubstituted succinates which were reduced with LiAlH₄ to 2,3-disubstituted butanediols-1,4 in nearly quantitative yields. Some 2,3-disubstituted butanediols-1,4 were cyclodehydrated under reduced pressure with KHSO₄ to 3,4-disubstituted tetrahydrofurans or acetylated and the diacetyl compounds pyrolyzed at 525°C to 2,3 disubstituted butadienes-1,3. The length of the alkyl chains of the 2,3-dialkylsuccinates and consequently the 2,3-dialkylbutanediols-1,4 ranged from C₂ to C₁₆. 2,3-Disubstituted butanediols-1,4, 2,3-disubstituted butadienes-1,3, and 3,4-disubstituted tetrahydrofurans are interesting monomers for polymerization experiments.     

Investigation of nitrogen- and sulfur-containing heterocyclic compounds

The halogenation of 2,3-dimethylpyrazino[2,3-b][1,4]thiazin-6-one with bromine or 1 mole of sulfuryl chloride gives 7-bromo-and 7-chloropyrazino[2,3-b][1,4]thiazin-6-ones, while 2 moles of sulfuryl chloride give 7,7-dichloropyrazino[2,3-b][1,4]thiazin-6-one. A number of 7-amino-and 7,7-diaminopyrazino[2,3-b][1,4]thiazin-6-ones were obtained by the reaction of the appropriate halo derivatives with amines. Some of the pyrazino[2,3-b][1,4]thiazin-6-one derivatives inhibit the growth of interweavable tumors in animals.See [3] for communication XX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1498–1501, November, 1971.     

Derivatives of 1,1,2,2-tetraaminoethane: II. Condensation of 4,5-diacetoxy-1,3-diacetylimidazolidine and 2,3-diacetoxy-1,4-diacetylpiperazine with nitrogen-containing nucleophiles

Reactions of 4,5-diacetoxy-1,3-diacetylimidazolidine and 2,3-diacetoxy-1,4-diacetylpiperazine with acetamide and ethyl carbamate gave 1,3-diacetyl-4,5-bis(acetylamino)imidazolidine, 1,4-diacetyl-2,3-bis(acetylamino)piperazine, 1,3-diacetyl-4,5-bis(ethoxycarbonylamino)imidazolidine, and 1,4-diacetyl-2,3-bis(ethoxycarbonylamino)piperazine, respectively. Condensation products of 4,5-diacetoxy-1,3-diacetylimidazolidine and 2,3-diacetoxy-1,4-diacetylpiperazine with urea, furazan-3,4-diamine, and 4-phenylfurazan-3-amine were isolated.     

Synthesis of condensed quinoxalines. Part II

A novel efficient synthesis of fluorescent, fused quinoxalines was achieved. 7-Triazolyl-1,4-dioxino[2,3-b]-quinoxalines were synthesized by the diazotisation of 7-amino-1,4-dioxino[2,3-b]quinoxaline and coupling with selected aromatic amines followed by air oxidation. Diazotised aryl amines were coupled with 7-amino-1,4-dioxino[2,3-b]quinoxalines followed by subsequent air oxidation afforded 1,4-dioxino[2,3-b]quinoxalino-[6,5-d]1,2,3-triazoles. 7-Amino-1,4-dioxino[2,3-b]quinoxaline was condensed with conjugated enol ethers followed by cyclization in dowtherm resulted in 1,4-dioxino[2,3-b]quinoxalino[6,5-b]pyridines.     

Amination of naphthoquinones with azidotrimethylsilane

A new method for the synthesis of aminonaphthoquinones from 1,2- or 1,4-naphthoquinones and azidotrimethylsilane is described. In a similar manner 2,3-epoxy-2,3-dihydro-1,4-naphthoquinone was transformed into 2-amino-3-hydroxy-1,4-naphthoquinone. The mechanism of these transformations and the formation of by-products are discussed.

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Aminierung von Naphthochinonen mit Azidotrimethylsilan

Zusammenfassung Eine neue Methode zur Herstellung von Aminonaphthochinonen aus 1,2- oder 1,4-Naphthochinonen und Azidotrimethylsilan wird beschrieben. In analoger Weise wurde 2,3-Epoxy-2,3-dihydro-1,4-naphthochinon in 2-Amino-3-hydroxy-1,4-naphthochinon umgewandelt. Eine mechanistische Deutung dieser Umsetzung und die Bildung von Nebenprodukten wird diskutiert.

     

Synthesis of Mixed Aryl 2,3-Diarylsulphanyl-1,4-naphthoquinones

The reaction of 2-arylsulphanyl-1,4-napththoquinone with aromatic thiols and sodium dithionate leads to bis-2,3-(arylsulphanyl)naphthalene-1,4-diols in high yield. Corresponding oxidized products, namely 2,3-diarylsulphanyl-1,4-naphthoquinones, are prepared in near quantitative yield by a copper(II)-catalyzed aerial oxidation reaction of bis-2,3-(arylsulphanyl)naphthalene-1,4-diols under mild condition.     

Reaction of 2-bromomethyl-1,3-thiaselenole with thiourea: en route to the first representatives of 2-(organylsulfanyl)-2,3-dihydro-1,4-thiaselenines

The regioselective reaction of 2-bromomethyl-1,3-thiaselenole 1 with thiourea is accompanied by rearrangement, expanding the ring to afford the corresponding six-membered isothiuronium salt, 2-[amino(imino)methyl]sulfanyl-2,3-dihydro-1,4-thiaselenine hydrobromide 2, a synthon of the 2,3-dihydro-1,4-thiaselenin-2-ylthiolate anion. The latter was used for the synthesis of the first representatives of 2-(organylsulfanyl)-2,3-dihydro-1,4-thiaselenines 3a–g, bis(2,3-dihydro-1,4-thiaselenin-2-yl) disulfide 5 and 1,6-bis(2,3-dihydro-1,4-thiaselenin-2-ylsulfanyl)hexane 6.     

两种含杂环的氨基萘醌化合物的合成

以2,3-二氯-1,4-萘醌为主要原料,分别与吗啡啉和糠胺在一定条件下反应生成2种含杂环的氨基萘醌类化合物。2,3-二氯-1,4-萘醌与吗啡啉及2,3-二氯-1,4-萘醌与糠胺物质的量比均为1∶2,反应温度为60℃,溶剂为乙醇。2,3-二氯-1,4-萘醌与吗啡啉反应时间为1 h,产物2-氯-3-吗啡啉基萘-1,4-二酮(a)收率为93.5%;2,3-二氯-1,4-萘醌与糠胺反应时间为4 h,产物N~2,N~3-二(2-呋喃甲基)-1,4-二((2-呋喃甲基)亚胺)-1,4-二氢化萘-2,3-二氯化铵(d)收率为46.7%。对产物进行IR、Uv、MS和H-NMR等分析表征。     

Reactions of 1,2-diaza-1,3-dienes with thiol derivatives: a versatile construction of nitrogen/sulfur containing heterocycles

The synthesis of substituted 2,3-dihydro-1,4-thiazines, fused cycloalkyl-1,4-thiazines, 1,4-benzothiazines and fused cycloalkyl-1,4-benzothiazines by 1,4-addition of 1,2-aminothiols to 1,2-diaza-1,3-dienes bearing carboxylate, carboxamide, or phosphorylated groups and subsequent internal heterocyclization is described. The reaction of carboxylated 1,2-diaza-1,3-butadienes with 2-(butylamino)ethanethiol affords 1,4-thiazinan-3-ones. The solid-phase reaction of polymer-bound 1,2-diaza-1,3-butadienes with 1,2-aminothiols produces 2,3-dihydro-1,4-thiazines and 1,4-benzothiazines.