某些官能化手性氮杂环丙烷衍生物的合成及其结构

手性元5-(R)-(1R,2S,5R)-孟氧基-3-溴-2(5H)-呋喃酮(3)与氮亲核试剂伯胺(4), 通过串联的不对称Michael加成/分子内亲核取代反应得到了具有两个新的手性中心的1R,5S-6-烷基-6-氮杂-2R-孟氧基-3-氧杂-4-氧代二环[3,1,0]己烷(5a～5d), 产率41%～51%, e.e.≥98%. 后者经LiAlH₄还原得到N-烷基-2,3-双(羟甲基)氮杂环丙烷(6a～6d), 产率66%～91%. 化合物5和6通过元素分析, IR, ¹H NMR, ¹³C NMR, MS以及X射线晶体分析, 测定了它们的化学结构及立体化学构型. 本文为N-烷基氮杂环丙烷类化合物的合成提供了一种有效途径.     

无膦钯催化Heck反应合成新型芳维A酸类化合物

考察了以二环己基胺作配体的无膦钯催化Heck反应条件, 建立起一种新型的无膦钯催化Heck反应体系. 应用该体系可高收率(72%～84%)、高立体选择性(83%～95%)合成二取代和三取代二苯烯类化合物. 以2,4,5-三甲氧基苯乙烯、α-细辛脑为原料, 合成了4个尚未见文献报道的新型二苯烯类芳维A酸甲酯(3a, 3b, 4a, 4b), 并且在温和的水解体系[LiOH, V(THF)∶V(H₂O)＝5∶1]下顺利得到了它们的水解产物芳维A酸(5a, 5b, 6a, 6b), 产物通过¹H NMR, ¹³C NMR, IR和MS进行了结构确认.     

含均三唑环的新型联苯四唑衍生物的合成及抗菌活性

通过4-芳基-5-(4-吡啶基)-1,2,4-三唑-3-硫醇(1)和2-三苯基甲基-5-(4′-溴甲基联苯-2-基)-四唑(5)反应, 制得一系列新的S-烷基化产物(6), S-烷基化产物在酸性条件下脱保护, 得到了14个未见文献报道的含1,2,4-三唑类联苯四唑(7a～7n)衍生物. 结构经元素分析, IR, NMR及FAB-MS确认. 对大肠杆菌、链球菌、枯草杆菌、金黄色葡萄球菌初步抑菌试验证明, 多数化合物表现了较好的抑菌活性.     

一种含有手性联萘“铰链”单元的环芳分子的设计、合成及表征

基于联萘衍生物手性构型高度稳定以及联萘结构中2个萘平面的两面角可以在一定范围内张合的特点, 分别以光学活性的(R)和(S)-2,2'-二乙炔基-1,1'-联萘为模板, 设计了一种含有8个“铰链”结构单元的新的环芳分子¾—(R,R,R,R,R,R,R,R)-3和(S,S,S,S,S,S,S,S)-3. 其合成路线涉及间苯基连接桥的链接, 保护基的脱去和控制导入以及分子间偶合等步骤. 用MS, IR, UV-Vis, ¹H和¹³C NMR以及元素分析等技术对中间体和目标化合物进行了结构表征. 测定并比较了2个目标化合物的比旋光度[α]_D和圆二色(CD)性质. 在CH₂Cl₂溶液中, 两个异构体(R,R,R,R,R,R,R,R)-3和(S,S,S,S,S,S,S,S)-3的[α]_D²⁵值分别为－911.8和＋908.6, 并且它们的CD谱表现出对称的镜像特征．这些实验结果清楚地反映了它们之间的对映异构关系.     

氟伐他汀钠的合成

以氟苯为起始原料,通过两步反应得N-(4-氟苯甲酰甲基)-N-(1-甲基乙基)苯胺(5);5在ZnCl2存在下环化得3-(4′-氟苯基)-1-(1′-甲基乙基)吲哚(6);6与3-N-甲基-N-苯基胺基丙烯醛发生Vilsmeier-Haauc反应得(E)-3-[3′-(4″-氟苯基)-1′-(1″-甲基乙基)吲哚-2′-基]-2-丙烯醛(8);8经缩合、还原、水解得氟伐他汀钠,总收率10.5%.     

2-取代硫醚-5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑类化合物的合成、结构与体外抗癌活性

以天然产物没食子酸为原料经醚化、酯化、酰肼化、成盐、闭环、硫醚化六步反应合成了6个2-取代硫醚-5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑类衍生物, 釆用铟催化下水相合成目标化合物8, 具有反应条件温和, 合成收率高的特点; 用IR, ¹H NMR, ¹³C NMR和元素分析对各化合物进行了表征及结构确证, 并用X射线单晶衍射法测定了化合物8a [2-(2-氯-5-吡啶甲基)硫醚-5-(3,4,5-三甲氧基苯基)-1,3,4-噻二唑]的晶体结构, 采用MTT法进行了新化合物抑制PC3和BGC-823癌细胞体外试验, 结果表明在5μmol•L^－1浓度下化合物8e对PC3的抑制活性为55.71%. 化合物8b对BGC-823细胞抑制活性为66.21%.     

两种取代二茂铁基三甲基硅烷基氰醇醚的合成及晶体结构

通过两种取代的乙酰基二茂铁与三甲基氰硅烷的加成反应, 得到两种取代二茂铁基三甲基硅烷基氰醇醚的晶体: 1-(1-氰基-1-三甲基硅烷氧基乙烷基)二茂铁(1), 1,1'-二(1-氰基-1-三甲基硅烷氧基乙烷基)二茂铁(2), 用X射线单晶衍射、元素分析、红外光谱和核磁共振氢谱对分子结构进行了表征. 测试结果表明: 晶体1属正交晶系, Pbca空间群, a＝1.1995 nm, b＝1.2441 nm, c＝2.2183 nm, Z＝8, R₁＝0.0456, wR₂＝0.0880; 晶体2属正交晶系, Pna2(1)空间群, a＝2.0715 nm, b＝0.6440 nm, c＝1.8411 nm, Z＝4, R₁＝0.0485, wR₂＝0.0866. 晶体结构表明, 分子中都存在超共轭效应.     

利伐沙班关键杂质的合成

以对溴硝基苯为原料,经偶联、胺基保护、亲核取代、硝基还原、环氧开环、环合、脱保护和胺基酰化反应合成了利伐沙班的二胺杂质--5-氯-N-【【(5S)-2-氧代-3-｛4-［5-氯-噻吩-2-甲酸-N-(2-甲基氨基甲酰基甲氧基乙基)酰胺基］苯基｝-1,3-噁唑烷-5-基】甲基】-2-噻吩甲酰胺,其结构经¹H NMR, ¹³C NMR, DEPT135°, ¹H-¹HCOSY, HSQC, HMBC和MS（ESI）确证。     

不同氟取代基对苝酰亚胺电子迁移率的影响

利用空间电荷限制电流(SCLC)法测试了二种氟代苝酰亚胺的电子迁移率, 一种是N,N'-二(五氟代苯基)-3,4,9,10-苝四羧基二酰亚胺(1), 另一种是N,N'-二(1,1-二氢十五氟代辛基)-3,4,9,10-苝四羧基二酰亚胺(2). 结果发现, 化合物2的电子迁移率要比1高1～2个数量级. UV-Vis, XRD, SEM和AFM等表征手段证明, 这一现象可以用不同的氟取代基导致不同的聚集态结构来解释: 对于化合物1而言, 苯环平面与苝环平面之间存在大的夹角, 破坏了苝酰亚胺分子的平面性, 再加上刚性的氟代苯环大的空间位阻作用, 化合物1分子无法依靠相邻苝环之间的重叠排列而结晶, 只能无序堆积形成非晶膜; 与之相反, 在化合物2分子中苝环上的端基是柔性的锯齿状氟代烷基链, 空间位阻小, 化合物2分子能通过相邻苝环之间相互接近而形成的π-π偶合作用而结晶, 因此有利于电子在苝酰亚胺分子间的跳跃传输.     

新型3,6-二取代-1,2,4-三唑[3,4-b]-1,3,4-噻二唑衍生物的合成、表征及生物活性

以4-氨基-5-[2-(4-氯苯氧甲基苯并咪唑)-1-亚甲基]-3-巯基-1,2,4-三唑(6)和不同的芳香酸为原料, 在三氯氧磷的作用下环化合成了17个新型3-[2-(4-氯苯氧甲基苯并咪唑)-1-亚甲基]-6-芳基-1,2,4-三唑[3,4-b]-1,3,4-噻二唑衍生物7. 利用IR, ¹H NMR和元素分析对新化合物6和7的结构进行了表征. 初步的生物活性实验结果表明, 化合物7a和7b在20 μg/mL时对大肠杆菌甲硫氨酰氨肽酶(EcMetAP1)具有较高的抑制活性, 抑制率分别为87.26%和82.62%, 化合物7f, 7h和7l具有中等的抑制活性. 化合物7a～7q在20 μg/mL时对细胞分裂周期(cdc25B)磷酸酯酶均具有抑制活性, 其中化合物7b, 7g和7i在5 μg/mL时仍具有很高的抑制活性, 抑制率分别为98.76%, 83.87%和90.57%. 杀菌、杀虫、除草和植物生长调节活性筛选测定实验结果表明, 所测试的目标化合物7d～7e, 7h～7m和7o～7q均无活性.     

Efficient synthesis of (-)-gamma-lycorane alkaloid by two Bu3SnH-mediated radical cyclisations

An asymmetric induction using (S)-1-arylethylamine-based chiral auxiliary and two Bu(3)SnH-mediated radical cyclisations have been developed for a total synthesis of (-)-gamma-lycorane (1). The first cyclisation proceeded in 5-endo-trig manner with moderate diastereoselectivtiy to give (3aR,7aR)-octahydroindol-2-one 6b as the major product using alpha-iodo-N-(6-oxocyclohexen-1-yl)-N-[(S)-1-phenylethyl] acetamide (5b). In the second cyclisation, the radical precursor 8 was used as substrate to construct the optically active lycorane skeleton 15 which was reduced using LiAlH4 into (-)-gamma-lycorane (1).     

C3-chiral tripodal amido complexes

A comprehensive study into the coordination chemistry of two C3-chiral tripodal amido ligands has been carried out. The amido ligands contain a trisilylmethane backbone and chiral peripheral substituents. The amine precursors. HC(SiMe2NH[(S)-1-phenylethyl]]3 (1) and HC[SiMe2NH[(R)-1-indanyl]]3 (2) were found to be in equilibrium in solution with the cyclic diamines HC[SiMe2N[(S)-1-phenylethyl]2](SiMe2NH-[(S)-1-phenylethyl]] (3) and HC[SiMe2NH[(R)-1-indanyl]][SiMe2NH[(R)-1-indanyl]) (4), which are generated upon ejection of one molecule of the chiral primary amine. Reaction of these equilibrium mixtures with three molar equivalents of butyllithium instantaneously gave the trilithium triamides HC[SiMe2N(Li)[(S)-1-phenylethyl]]3 (5) and HC[SiMe2N(Li)[(R)-1-indanyl]]3 (6), both of which were characterised by an X-ray diffraction study. Both lithium compounds possess a central heteroadamantane core, in which the two-coordinate Li atoms are additionally weakly solvated by the three aryl groups of the chiral peripheral substituents, the Li-C contacts being in the range of 2.65-2.73 A. Reaction of 5 and 6 with [TiCl4(thf)2] and ZrCl4 gave the corresponding amido complexes [TiCl-[HC[SiMe2N[(S)-1-phenylethyl]]3]] (7), [TiCl(HC[SiMe2N[(R)-1-indanyl]]3]] (8), [ZrCl[HC[SiMe2N[(S)-1-phenylethyl]]3]] (9) and [ZrCl[HC[SiMe2N[(R)-1-indanyl]]3]] (10), respectively. Of these, compound 7 was structurally characterised by X-ray structure analysis and was shown to possess a C3-symmetrical arrangement of the tripod ligand. The chiral anionic dinuclear complex [Li-(OEt2)4][Zr2Cl3[HC[SiMe2N[(S)-1-phenylethyl]]3]2] (11) was isolated from reaction mixtures leading to 9. An X-ray diffraction study established its dimeric structure, in which the chiral amido ligands cap the two metal centres, which are linked through three symmetrically arranged, bridging chloro ligands. Reaction of 9 and 10 with a series of alkyl Grignard and alkyllithium reagents yielded the corresponding alkylzirconium complexes. X-ray structure analyses of [Zr(CH3)[HC[SiMe2N[(S)-1-phenylethyl]]3]] (12) and [Zr(CH3)-[HC[SiMe2N)[(R)-1-indanyl]]3]] (20) established their detailed molecular arrangements. While the reaction of 12 with the aryl ketones PhC(O)R (R = CH = CHPh, iPr, Et) gave the corresponding C-O insertion products, which contain an additional chiral centre in the alkoxy group, with low stereoselectivity (0-40% de). The corresponding conversions with several aryl aldehydes yielded the alkoxo complexes with high stereoselectivity. Upon hydrolysis, the chiral alcohols were isolated and shown to have enantiomeric excesses between 68 and 82%. High stereodiscrimination was also observed in the insertion reactions of several chiral ketones and aldehydes. However, this was shown to originate primarily from the chirality of the substrate. In analogous experiments with carbonyl compounds, the ethyl- and butyl-zirconium analogues of 12 did not undergo CO insertion into the metal-alkyl bond. Instead, beta-elimination and formal insertion into the metal-hydride bond occurred. It was found that the elimination of the alkene was induced by     

Application of N-(ω-bromoalkyl)tetrazoles for the preparation of bitopic ligands containing pyridylazole chelators or azole rings as building blocks for iron(II) spin crossover polymeric materials

1-(3-Bromopropyl)tetrazole, 2-(3-bromopropyl)tetrazole, 1-(4-bromobutyl)tetrazole, and 2-(4-bromobutyl)tetrazole were synthesized with the aim to prepare flexible bitopic ligands contaning 1- or 2-substituted tetrazole ring linked through 1,3-propylene or 1,4-butylene spacer with pyridylazole or azole unit. Twenty-six novel ligands i.e., α-(pyridylazolyl)-ω-(tetrazolyl)alkanes, α-(tetrazolyl)-ω-(1,2,3-triazolyl)alkanes, and α-(tetrazol-1-yl)-ω-(tetrazol-2-yl)alkanes were prepared by an alkylation of sodium salts of 5-(2-pyridyl)tetrazole, 3-(2-pyridyl)-1,2,4-triazole, 3-(2-pyridyl)pyrazole, 1,2,3-triazole, and 1,2,3,4-tetrazole with N-(ω-bromoalkyl)tetrazoles. An alkylation of 5-(2-pyridyl)tetrazole, 1,2,3,4-tetrazole, and 1,2,3-triazole afforded both N1- and N2-regioisomer whereas in the case of 3-(2-pyridyl)-1,2,4-triazole and 3-(2-pyridyl)pyrazole only N1 isomers were isolated. The positions of alkylation were confirmed by X-ray diffraction studies of 1-(5-(2-pyridyl)tetrazol-2-yl)-4-(tetrazol-1-yl)butane, 1-(3-(2-pyridyl)-1,2,4-triazol-1-yl)-4-(tetrazol-2-yl)butane, 1-(3-(2-pyridyl)pyrazol-1-yl)-4-(tetrazol-1-yl)butane, and 1-(tetrazol-1-yl)-4-(1,2,3-triazol-1-yl)butane. Preliminary investigations of magnetic properties of iron(II) complex with 1-(3-(2-pyridyl)-1,2,4-triazol-1-yl)-4-(tetrazol-1-yl)butane revealed that obtained product exhibit thermally induced spin transition accompanied by the thermochromic effect.     

Chemical constituents of malagasy liverworts, part V: prenyl bibenzyls and clerodane diterpenoids with nitric oxide inhibitory activity from Radula appressa and Thysananthus spathulistipus

3Beta,4beta:15,16-diepoxy-13(16),14-clerodadiene (1) and a new clerodane diterpenoid designated thysaspathone (2) were isolated from the liverwort Thysananthus spathulistipus, while Radula appressa produced radulannin A (3), radulannin L (4), 2-geranyl-3,5-dihydroxybibenzyl (5), 2(S)-2-methyl-2-(4-methyl-3-pentenyl)-7-hydroxy-5-(2-phenylethyl) chromene (o-cannabichromene) (6), 6-hydroxy-4-(2-phenylethyl) benzofuran (7), and o-cannabicyclol (8). All of the isolated compounds inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and the greatest inhibition was attributed to compound 5, with an IC50 value of 4.5 microM.     

Four new 2-(2-phenylethyl)chromone derivatives from withered wood of Aquilaria sinensis

Four new chromone derivatives, 5-hydroxy-6-methoxy-2-(2-phenylethyl)chromone (1), 6-hydroxy-2-(2-hydroxy-2-phenylethyl)chromone (2), 8-chloro-2-(2-phenylethyl)-5,6,7-trihydroxy-5,6,7,8-tetrahydrochromone (3), 6,7-dihydroxy-2-(2-phenylethyl)-5,6,7,8-tetrahydrochromone (4) were isolated from the MeOH extract of withered wood of Aquilaria sinensis, together with seven known constituents of agarwood.     

Synthesis and crystal structure of optically active 2-[benzyl(phenyl)amino]ethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2,6-dim ethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate (NZ-105).

(S)-2-[Benzyl(phenyl)amino]ethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2, 6-dimethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate ((S)-NZ-105) and R isomer were synthesized through the fractional crystallization of (S)-2-Methoxy-2-phenylethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2, 6-dimethyl-4-(3-nitrophenyl)-3-pyridinecarboxylate. Calcium antagonism activity was found to reside in the S isomer from single crystal X-ray diffraction analysis.     

Synthesis of N-methyl-N-[(1S)-1-[(3R)-pyrrolidin-3-yl]ethyl]amine

N-Methyl-N-[(1S)-1-[(3R)-pyrrolidin-3-yl]ethyl]amine (1)(1) is a key intermediate in the preparation of premafloxacin (2), which was under development as an antibiotic for use against pathogens of veterinary importance. This paper describes the development of a practical, efficient, and stereoselective process for the preparation of 1 from isobutyl (3S)-3-[methyl[(1S)-1-phenylethyl]amino]butanoate (5c). The key steps in the synthetic sequence are an asymmetric Michael addition, which yields 5c, and a stereoselective alkylation, which yields (3S,4S)-3-allyl-1,4-dimethylazetidin-2-one (17).     

Synthesis and structures of 5-(pyridyl)tetrazole complexes of Mn(II)

New Mn(II) complexes containing 5-(2-pyridyl)tetrazole, 5-(3-cyano-4-pyridyl)tetrazole or 5-(4-pyridyl)tetrazole ligands are described. The complexes are prepared by reaction of the corresponding cyanopyridines with sodium azide in the presence of Mn(II) salts. All the complexes have been characterized by X-ray crystallography, which reveals that 5-(pyridyl)tetrazole ligands can coordinate to Mn through either type of nitrogen atom in the tetrazole residue or via the pyridyl group. In the solid state, extended 2D and 3D structures are produced through networks of hydrogen bonding (involving water molecules and the tetrazolate residue). Acidification of the complexes produces the corresponding free 5-(pyridyl)-1H-tetrazole.     

Six new 2-(2-phenylethyl)chromones from Agarwood

Six new chromones, 6-methoxy-2-[2-(3-methoxy-4-hydroxyphenyl)ethyllchromone (2), 6,8-dihydroxy-2-(2-phenylethyl)chromone (3), 6-hydroxy-2-[2-(4-hydroxyphenyl)ethyl]chromone (4), 6-hydroxy-2-[2-(2-hydroxyphenyl)ethyl]chromone (5), 7-hydroxy-2-(2-phenylethyl)chromone (6), and 6-hydroxy-7-methoxy-2-(2-phenylethyl)chromone (7) were isolated from the ether extract of agarwood in addition to a known compound, 2-(2-phenylethyl)chromone or flidersiachromone (1). Their structures were determined by spectroscopic methods including UV, IR, and NMR spectral data and comparisons with the calculated values using the hydroxyl and methoxyl substituent increments of the chromone ring.     

Cyclisation of (R)- and (S)-N-allyl-N-(1-phenylethyl) methoxycarbonylacetamide mediated by Mn(III): Preparation and structural assignment of 3-aza-2-oxobicyclo[3.1.0]hexanes

(R)- and (S)-N-allyl-N-(1-phenylethyl)methoxycarbonylacetamide, 5 and 6, underwent oxidative cyclisation mediated by Mn(III), to give easily separable diastereomeric mixtures of 3-aza-2-oxobicyclo[3.1.0]hexanes 8a,b and 9a,b, respectively, whose structures were assigned on the basis of ¹H NMR spectra and then confirmed by X-ray diffraction analysis of the derivatives 11b and 14.