5,6-二亚甲基二环[2.2.1]庚-2-醇的四种立体异构体的合成与构型

本文报道了手性桥环化合物5,6-二亚甲基二环[2.2.1]庚-2-醇的四种光学纯立体异构体的合成及其比旋光度[α]~D, 并通过它们之间的相互关系, 确定了它们的绝对构型.     

DL-苯丙氨酸-1-14C化学合成及酶促拆分

本文报道 DL-苯丙氨酸-1-(14)~C 的合成,并利用嗜热菌蛋白酶酶促拆分光学异构体。化学产率和放化产率一致,可达67%,标记化合物的放化纯度高于95%。     

酶催化拆分制备手性2-氯-1-(2,4-二氟苯基)乙醇及 光学活性抗真菌药物的合成

用Pseudomonas stutzeri脂肪酶催化转酯化反应动力学拆分外消旋体法制备高对映体纯的手性2-氯-1-(2,4-二氟苯基)乙醇, 得到95.8% ee值的(R)-异构体和94.5% ee值的(S)-异构体, 以此手性醇为关键中间体合成了4种具有抗真菌活性的光学活性化合物α-氯代苄氧基-β-(1-咪唑基)-2,4-二氟乙苯硝酸盐. 纸片扩散法测试体外抗真菌活性结果表明, 对各种念珠菌(Candida species) (R)-5a和(R)-5b具有与氟康唑相当的抗菌活性, 特别是对氟康唑耐药的烟曲霉菌(Aspergillus fumigatus), 5a, 5b及其两种光学活性异构体均有优异的抗菌活性, 而且(R)-异构体的活性明显高于(S)-异构体和外消旋体.     

2-芳基-4-甲基-2,3,4,5-四氢-(1,5)-苯并硫氮杂 的晶体结构研究

本文报道2-p-硝基-4-甲基-2,3,4,5-四氢-(1,5)-苯并硫氮杂 的两顺反式异构体的晶体结构. 顺式异构体属正交晶系, 空间群为反式异构体属单斜晶系, 空阒空间群为 , 晶胞参数:晶体结构由SHELXTL直接法程序解出, 用块矩最小二乘法修正, 最后的偏离因子:顺式异构体结构分析表明: 顺式异构体为类椅式构象, 反式异构体类扭船式构象. 这为进一步归纳这类化合物的结构特征和立体化学规律提了条件.     

Scobidiynediol的合成及绝对构型

本文报道了以光学活性乳酸为手性元对目标化合物的所有可能的四个异构体所进行的合成。根据合成样品与天然产物的核磁及旋光数据比较，标题化合物的相对及绝对构型都得以完全确立，其完整结构定为(2S,3S)-4,6-庚二炔-2,3-二醇。     

CycloSil-B手性柱分离2-氯丙酸酯光学异构体

采用气相色谱法在七(2,3-二-O-甲基-6-叔-丁基二甲基硅烷)-β-环糊精(CycloSil-B)手性色谱柱上分离2-氯丙酸酯光学异构体.考察了2-氯丙酸酯结构和柱温对分离效果影响;在光学异构体分离过程中对热力学参数的计算,探讨光学异构体分离过程的驱动力和手性识别机理.结果表明,随着2-氯丙酸酯的酯基团的链长增加、体积增大,2-氯丙酸酯光学异构体的分离因子(α)和分离度(RS)随之减小;2-氯丙酸正构醇酯光学异构体的分离因子对数(lnα)与酯基团的立体效应Taft Es常数之间具有较好的相关性.当柱温为86 ℃时其回归方程为: lnα＝0.03044-4.754(Es)6(r=0.9991).随着柱温升高,2-氯丙酸酯光学异构体的容量因子(k′)、分离因子(α)和分离度(RS)也随之减小;当柱温小于82 ℃时,2-氯丙酸甲酯和乙酯光学异构体的分离度(RS)大于1.5.2-氯丙酸正构醇酯光学异构体在CycloSil-B色谱柱上的分离过程是一个焓驱动过程并存在着焓熵补偿关系.β-环糊精衍生物表面与2-氯丙酸酯之间的相互作用在其分离过程中起了重要作用,特别是酯基团的大小对2-氯丙酸酯光学异构体的分离起着决定性作用.     

N-(6-甲基-2-亚甲基吡啶)-( )-樟脑亚胺体系的不对称烷基化反应

目前,不对称合成光学活性化合物取得了较大进展,不对称合成α-氨基酸、β-氨基醇、α-取代苄胺的报道很多。但是,不对称合成生物碱类物质——α-取代氨甲基吡啶类化合物还未见文献报道,而此类化合物有潜在的应用前景。为此,我们以( )-樟脑为手性试剂     

甾体不对称合成的研究——新光学活性合成原——(2R,3S)-( )-2-乙基-2-(3′-羰基-4′-烯)-戊基-3-乙酰氧基-环戊酮的合成

本文报道一个新的可以广泛应用于甾体全合成的光学活性合成原6的合成.从2-乙基-1,3-环戊二酮 8与 γ-羰基亚砜 12b反应所得之对称三酮 9b经啤酒酵母菌不对称还原得到(2R,3S)-(—)-羟基化合物14,从(2R,3S)-(—)-14所得的(2R,3S)-( )-16的甲磺酸酯或对一甲苯磺酸酯用三乙胺消除即得目的物(2R,3S)-( )-6.微生物不对称还原产生的14的绝对构型是把它转变成已知化合物(2R,3S)-( )-17而得到证明的。     

4-(3-羟基丁氧基)-2-丁醇光学异构体的合成

以廉价易得的(R/S)-3-羟基丁酸甲酯(4a/4b)为起始原料,经过5步反应,以44%~50%的总收率合成了4-(3-羟基丁氧基)-2-丁醇光学异构体1a~1c,为相应的手性新药的开发提供了新途径.     

1-{[2-(1,3-二苯基-1H-萘[1,2-e][1,3]-2-噁嗪基)环己氨基]-苯基-甲基}-2-萘酚的合成与晶体学表征

具有光学活性的1,2-二氨基环己烷及其衍生物作为手性辅剂或手性配体被广泛地用在催化不对称合成中[1-3].最近,我们在无溶剂的条件下,利用(1R,2R)-1,2-二氨基环己烷与2-萘酚、苯甲醛反应一锅法合成手性配体1的过程中,没有得到目标化合物1,得到了一种新的1,2-二氨基环己烷衍生物2.经元素分析,IR,1H NMR,13C NMR,MS以及X射线单晶衍射,确定了2的结构,结果表明2中含有五个手性中心.本文报道2的合成与晶体学表征(Scheme 1).     

Synthesis of chlorinated 2-(aminomethyl)- and 2-(alkoxymethyl)pyrroles

The synthesis of chlorinated 2-(hydroxymethyl)-, 2-(alkoxymethyl)- and 2-(aminomethyl)pyrroles via aromatization of 2-aryl-3,3-dichloro-5-(bromomethyl)pyrrolines and via reduction of 2-formyl- and 2-cyanopyrroles is described. The former methodology also provided new 2-[(alkyl- or phenylamino)methyl]pyrroles and a 2-(phosphonomethyl)pyrrole. Halogenated and methylene-spaced functionalized pyrroles are of particular interest for their pronounced physiological activities.     

1-(Fluoren-2-yl)-2-(2-azafluoren-3-yl)ethene and 1-(fluoren-2-yl)-2-(2H,2-methylindeno[2,3-c]pyridine)ethene

Condensation of 3-methyl-2-azafluorene with 2-formylfluorene results in the formation of a compound containing a polyconjugated system and two acidic CH centers, namely, 1-(fluoren-2-yl)-2-(2-azafluoren-3-yl)ethene. The conversions of this compound upon treatment with alkali have been studied by electronic absorption spectroscopy. The methyl iodide derivative of this base was used as an intermediate in the preparation of a pseudo-azulene, 1-(fluoren-2-yl)-2-(2H, 2-methylindeno[2,3-c]pyridine)ethene.Translated from Khimiya Geterotsiklicheskikh Soedinenii No. 5, pp. 657–659, May, 1987.     

Preparation,molecular structures,and characteristic properties of (E)-1-(2-furyl)- and (E)-1-(2-thienyl)-2-(3-guaiazulenyl)ethylenes and (E)-1-(3-furyl)- and (E)-1-(3-thienyl)-2-(3-guaiazulenyl)ethylenes

Wittig reactions of 2-furaldehyde (20) [and thiophene-2-carbaldehyde (21)] with (3-guaiazulenylmethyl)triphenylphosphonium bromide (19) in ethanol containing NaOEt at 25 °C for 24 h under argon give (E)-1-(2-furyl)-2-(3-guaiazulenyl)ethylene (22E) and (E)-1-(2-thienyl)-2-(3-guaiazulenyl)ethylene (23E) in 53 and 36% yields. Similarly, Wittig reactions of 3-furaldehyde (29) [and thiophene-3-carbaldehyde (30)] with 19 under the same reaction conditions as for 20 and 21 afford (E)-1-(3-furyl)-2-(3-guaiazulenyl)ethylene (31E) and (E)-1-(3-thienyl)-2-(3-guaiazulenyl)ethylene (32E) in 32 and 46% yields. Molecular structures and characteristic properties as well as preparation of the title E (i.e., one of the geometrical isomers) forms, with a view to comparative study, are reported. Moreover, reactions of those conjugated π-electron systems with TCNE (=tetracyanoethylene) in benzene [and in DMF (=N,N-dimethylformamide)] at 25 °C for 24 h under argon yield unique products, possessing interesting molecular structures, respectively, whose characteristic properties and crystal structures are documented, also.     

An equilibrium analysis of the aqueous H+-MoO4(2-)-(HP)O(3)2- and H+-MoO4(2-)-(HP)O(3)2--HPO4(2-) systems

The speciation in the phosphitomolybdate system, H+-MoO4(2-)-(HP)O(3)2-, has been determined from combined potentiometric and 31P NMR measurements in 0.600 M Na(Cl) medium at 298(1) K. Potentiometric titration data were collected in the ranges 2.5<-log[H+]<6.2, 40.0相似文献   

Synthesis and properties of 2-(2-furyl)-and 2-(2-Thienyl)-1,3-benzoxazoles

Condensation of o-aminophenol with furoyl and thenoyl chlorides in 1-methylpyrrolidin-2-one gave, respectively, 2-(2-furyl)- and 2-(2-thienyl)-1,3-benzoxazoles in which the furan and thiophene rings showed no acidophobic properties. Reactions of 2-(2-furyl)- and 2-(2-thienyl)-1,3-benzoxazoles with electrophilic reagents (acylation, bromination, nitration, and sulfonation) afforded products of hydrogen replacement in both hetaryl and benzene rings, depending on the conditions.     

Synthesis and Crystal Structure of（E）-Ethyl 2-（5-（3-methyl-2-butenyloxy）-2-（3-（4-（3-methyl-2-butenyloxy）phenyl）acryloyl）phenoxy）acetate

The title compound,(E)-ethyl 2-(5-(3-methyl-2-butenyloxy)-2-(3-(4-(3-methyl-2-butenyloxy)phenyl) acryloyl) phenoxy)acetate(1),has been synthesized and characterized by FT-IR and 1H-NMR spectroscopy,ESI-MS,and X-ray single-crystal diffraction.FT-IR,1H-NMR and ESI-MS confirm the functional groups,particularly the ethyl groups in the ester moiety,of the compound.The single-crystal X-ray diffraction has revealed a monoclinic structure,space group P21/n with a = 14.6832(14),b = 7.7581(7),c = 23.075(2),β = 101.670(2)o,V = 2574.2(4) ?3,Z = 4,Dc = 1.235 g/cm,μ = 0.085 mm-1,and F(000) = 1024.The skeleton of chalcone in the molecular structure is coplanar.     

1-(Triorganylsilyl)-2-(triethoxysilyl)ethanes

Conclusions The conditions were found for the hydrosilylation of CH₂=CHSi(OC₂H₅)₃ with triorganylsilanes in the presence of H₂PtCl₆ · 6H₂O in isopropanol, which assured a high yield (>90%) of the 1-(triorganylsilyl)-2-(tri-ethoxysilyl)ethanes. These conditions were used to synthesize 27 new 1-(triorganylsilyl)-2-(triethoxysilyl)-ethanes.The addition of (C₂H₅O)₃SiH to (CH₂=CHSi(CH₃)₃ in the presence of the same catalyst gave 1-(trimethyl-silyl)-2-(triethoxysilyl)ethane in 98.6% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1622–1625, July, 1976.     

苯乙烯基氮氧杂芳烃间的交叉光二聚反应

用中压汞灯(λ > 300 nm)照射4-苯乙烯基吡啶、2-苯乙烯基苯并噁唑和5-苯基-2-苯乙烯基噁唑三种杂芳基乙烯单体中任意两种的硫酸水溶液，得到三种交叉二聚体.用高效液相色谱跟踪研究了交叉光二聚反应，发现每组反应生成三种光二聚体，其中二种为单体自身的光二聚体，而另外一种是两种不同单体的交叉光二聚体.交叉二聚体通过柱色谱分离得到，其顺式头对尾结构经紫外、红外、氢谱、碳谱和元素分析确定.用紫外光谱和高效液相色谱跟踪研究了交叉光二聚体的稀溶液在低压汞灯（λmax=254 nm）照射下的光解反应.研究发现交叉二聚体能够彻底发生光解，首先生成原来的反式单体，所生成的反式单体容易发生异构化而生成顺式单体，最终建立起反顺异构化平衡.     

Synthesis of 2-(2-methoxyethyl)- and 2-(2-thiomethoxyethyl)-aniline and related compounds

Summary 2-(2-Nitrophenyl)-ethanol (2) was methylated with dimethyl sulfate to give 2-(2-methoxyethyl)-1-nitrobenzene (3a) which then was reduced with hydrazine hydrate in the presence ofRaney nickel to 2-(2-methoxyethyl)-aniline (1a). Compound1a can be transformed into the N-monosilylated derivative4 by lithiation withn-butyllithium and subsequent reaction with chlorotrimethylsilane. Reaction of2 withp-toluenesulfonyl chloride yields 2-(2-nitrophenyl)-ethylp-toluenesulfonate (5), which reacts with sodium thiomethoxide to give 2-(2-nitrophenyl)-ethylp-toluenesulfonate (5), which reacts with sodium thiomethoxide to give 2-(2-thiomethoxyethyl)-1-nitrobenzene (3b).3b was reduced with hydrazine hydrate in the presence ofRaney nickel to yield 2-(2-thiomethoxyethyl)-aniline (1b). Ethyl (2-nitrophenyl)-acetate (6) could be dimethylated with methyl iodide in the presence of potassiumtert-butoxide and 18-crown-6 to give ethyl 2-methyl-2-(2-nitrophenyl)-propionate (7). Reduction of7 with lithium borohydride yields 2,3-dihydro-3,3-dimethyl-1H-indole (9) and 2-[(1-hydroxy-2-methyl)-2-propyl]-aniline (10).

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Synthese von 2-(2-Methoxyethyl)- und 2-(2-Thiomethoxyethyl)-anilin und verwandten Verbindungen

Zusammenfassung 2-(2-Nitrophenyl)-ethanol (2) wurde mit Dimethylsulfat zu 2-(2-Methoxyethyl)-1-nitrobenzol (3a) methyliert, das sich mit Hydrazinhydrat in Gegenwart vonRaney-Nickel zu 2-(2-Methoxyethyl)-anilin (1a) reduzieren läßt. Verbindung1a kann durch Metallierung mitn-Butyllithium und anschließende Reaktion mit Chlortrimethylsilan in dasN-monosilylierte Derivat4 umgewandelt werden. Reaktion von2 mitp-Toluolsulfonylchlorid ergab 2-(2-Nitrophenyl)-ethyl-p-Toluolsulfonat (5), das mit Natriumthiomethanolat zu 1-Nitro-2-(2-thiomethoxyethyl)-benzol (3b) reagiert.3b wurde mit Hydrazinhydrat in Gegenwart vonRaney-Nickel zu 2-(2-Thiomethoxyethyl)-anilin (1b) reduziert. Ethyl-2-(nitrophenyl)-acetat (6) kann mit Methyliodid in Gegenwart von Kalium-tert-butoxid und 18-Krone-6 zu Ethyl-2-methyl-2-(2-nitrophenyl)-propionat (7) dimethyliert werden. Reduktion von7 mit Lithiumborhydrid lieferte 2,3-Dihydro-3,3-dimethyl-1H-indol (9) und 2-[(1-Hydroxy-2-methyl)-2-propyl]-anilin (10).

     

Bioanalysis of (E)-5-(2-bromovinyl)-2'-deoxyuridine

(E)-5-(2-Bromovinyl)-2'-deoxyuridine is an antiviral drug that is experimentally used for modulation of the antitumour effect of fluoropyrimidines, such as ftorafur and 5-fluorouracil. The isolation of the analyte, in the presence of 5-fluorouracil, from the matrix is performed either by means of a simple protein precipitation (plasma) or by means of a liquid-liquid extraction with ethyl acetate (urine). Following pretreatment, the analyte is analysed by reversed-phase chromatography and quantified by absorbance detection at 307 nm. The minimum detectable concentration in plasma and urine samples is ca. 6 ng/ml. The recovery after deproteination of plasma samples is 75%, while after liquid-liquid extraction of urine the recovery amounts 92%. The degree of protein binding of the analyte, measured by ultrafiltration, is found to be 97%. These data allow the bioanalysis of (E)-5-(2-bromovinyl)-2'-deoxyuridine for pharmacokinetic studies.