光学活性双氨基酸的合成

光学活性的双氨基酸作为一类非天然的氨基酸合成子, 在医药、农药和肽类合成中有着重要的作用. 评述了近年来关于光学活性双氨基酸合成的进展.     

光学活性化合物的工业合成

本文介绍了光学活性化合物研究现状及发展趋势。并从技术和经济角度论述了工业合成光学活性化合物的可能性     

配位交换色谱在α-氨基酸光学拆分上的应用

对以不对称配位树脂为固定相,利用配位变换色谱拆分DL-氨基酸的国内外进展,进行了扼要的综述。     

光学活性氰醇的合成研究进展

光学活性氰醇是合成大量医药、农药产品的重要中间体。本文介绍了通过生物或化学催化剂进行外消旋底物的拆分或前手性底物的不对称化来制备光学活性氰醇的方法,重点讨论了有较大发展前景的有机溶剂中脂肪酶催化氰醇酯的动力学拆分的方法。     

天然手性源在光学活性菊酸合成中的应用

概述了用天然手性源制取光学活性菊酸的近期进展.讨论了利用天然手性试剂、酶以及微生物等对外消旋菊酸进行拆分,以天然氨基酸等作为手性诱导试剂进行不对称合成以及利用萜、碳水化合物、酒石酸等分子中天然存在的立体结构进行骨架改造和选择性合成.     

光学活性α—羟基膦酸酯的合成

扼要综述了近年来关于光学活性α－羟基膦酸酯的新合成方法,介绍了有关的手性试剂和对称反应,参考文献３２篇。     

不对称转换在α—氨基酸拆分中的应用

本文综述了不对称转换在α－氨基酸拆分中的应用，参考文献１９篇。     

硅手性中心的光学活性硅烷的合成与应用研究进展

硅手性中心的光学活性硅烷的合成及应用是有机化学领域一项极具魅力但同时又颇具挑战性的课题。本文从两个方面介绍了近年来该领域的最新研究进展,包括过渡金属或酶催化的前手性硅烷官能团化和手性底物或辅基诱导合成手性硅烷,以及手性硅烷在有机合成中的应用。     

氨基酸氧化酶催化合成非天然手性氨基酸研究进展

<正>非天然手性氨基酸是已经上市的和正在研发的手性药物、手性农药和手性食品添加剂的关键中间体[1-2].随着相关产业的发展,非天然手性氨基酸的市场需求与日俱增.非天然手性氨基酸不能像天然L-氨基酸一样采用发酵法生产,主要制备方法包括化学法和生物法.化学法包括化学不对称合成法和化学拆分法.化学不对称合成法采用价格昂贵的手性源、手性助剂或手性金属催化剂.化学拆分法采用手性酸为拆分剂,经历与消旋氨基酸成盐、解     

β-甲基苯丙氨酸的合成与拆分

β-甲基苯丙氨酸是一种含有两个手性中心的非基本氨基酸,本文先合成外消旋的β-甲基苯丙氨酸的衍生物,再通过酶促拆分,得到四种光学纯的异构体。     

Enzymatic preparation of optically active silicon-containing amino acids and their application

Optically active 3-trimethyl silylalanine (TMS-Ala) was prepared by hydrolysis of N-acetyl-dl-TMS-Ala catalyzed by acylase I (aminoacylase; N-acylamino-acid amidohydrolase, EC3.5.1.14). Acylase I from porcine kidney (PKA) was found to be more effective than that from Aspergillus melleus in the preparation of l-TMS-Ala. Under the optimized conditions, optically pure l-TMS-Ala (>99% enantiomeric excess, ee) was obtained with a 72% yield. Furthermore, a highly optically pure d-TMS-Ala (96% ee) could also be obtained with a 76% yield by chemical hydrolysis of the residual substrate. Enzymatic synthesis of peptides containing TMS-Ala was also attempted in ethyl acetate. Benzyloxycarbonyl (Z)-l-TMS-Ala served as the substrate for thermolysin, whereas l-TMS-Ala-OMe was inactive as the amino component. In the case of inhibitory activity of dipeptides toward thermolysin, l-Leu-(l-TMS-Ala) was found to be a more potent inhibitor than l-Leu-l-Leu, which is known to be one of the most effective inhibitors of thermolysin among the dipeptides consisting of natural aminoacids.     

N-二异丙氧磷酰化氨基酸的合成

以亚磷酸二异丙酯为磷酰化试剂、次氯酸钠为氯代试剂首次对20种常见的α-氨基酸进行了磷酰化.通过添加适量四丁基溴化铵为相转移催化剂,使用过量的亚磷酸二异丙酯以补偿其在强碱环境中的水解,从而提高了反应产率.所得产物经核磁共振谱、红外光谱和质谱鉴定结构并分析总结了该类化合物的谱图特征规律.     

Synthesis and properties of optically active amino acid based polyacetylenes bearing eugenol and fluorene moieties

Novel optically active amino acid based polyacetylenes bearing eugenol and fluorene moieties were synthesized, and their properties, including chiroptical ones, were analyzed. N‐[1‐(3,4‐Dimethoxyphenyl)‐2‐propyloxycarbonyl]‐L ‐alanine N′‐propargylamide ( 1 ), N‐[1‐(3,4‐dimethoxyphenyl)‐2‐propyloxycarbonyl]‐L ‐alanine propargyl ester ( 2 ), N‐(9‐fluorenylmethoxycarbonyl)‐L ‐alanine N′‐propargylamide ( 3 ), and N‐(9‐fluorenylmethoxycarbonyl)‐L ‐alanine propargyl ester ( 4 ) were polymerized with a rhodium‐zwitterion catalyst in tetrahydrofuran to afford the corresponding polymers with moderate molecular weights ranging from 10,800 to 17,300 in good yields. Because of the large specific rotation and circular dichroism (CD) signal, it was concluded that the poly(N‐propargylamide)s [poly( 1 ) and poly( 3 )] took a helical structure with a predominantly one‐handed screw sense. The solvent and temperature could tune the helical structure of poly( 1 ). On the other hand, the poly(propargyl ester)s [poly( 2 ) and poly( 4 )] exhibited only small specific rotations and CD signals. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 810–819, 2006     

Synthesis of optically active amino acids during asymmetric phase-transfer catalysis

Conclusions Asymmetric alkylation of the amino acid fragment of Ni²⁺ complexes of the Schiff bases of glycine with N-(2-pyridinecarbonyl)-o-aminobenzophenone and of alanine with N-(2-pyridinecarbonyl)-o-aminobenzaldehyde has been carried out under phase-transfer conditions using N-benzylcinchonidinium chloride as the chiral phase-transfer catalyst.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 631–635, March, 1989.     

Syntheses and radical polymerizations of optically active (meth)acrylamides having amino acid moieties

Syntheses and radical polymerizations of several (meth)acrylamides having L -amino acid moieties were examined. The monomers were prepared by the reactions of L -amino acid ester hydrochlorides with (meth)acryloyl chloride in the presence of triethylamine in satisfactory yields. Radical polymerizations of the monomers were carried out in the presence of AIBN (1 mol %) in bulk and in several solvents to afford the corresponding polymers in satisfactory yield. The glass transition temperatures and specific rotations of the polymers depended on the substituents of the L -amino acid moieties. Nearly the same specific rotations were observed for the monomers and the model compounds of the polymer units, N-pivaloyl amino acid methyl esters. On the contrary, the specific rotations of the polymers shifted to the negative direction in ca. 30°. The interaction between the polymer side chains might affect the changes in the specific rotations from monomers to polymers. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2619–2629, 1997     

(S)-2-芳基丙酸不对称合成研究进展

对(S)-2-芳基丙酸类非甾体抗炎药光学纯品的不对称合成方法进行了总结和概述，从中反映近年不对称合成中新概念、新方法和新技术的应用。     

Polycondensations of dicarboxylic acids and diols derived from optically active amino alcohols

Polycondensations of dicarboxylic acids with diols having amide moieties derived from optically active amino alcohols were carried out. Polymers with M _ns 8,700–17,400 were obtained by the polycondensations using 1.2 eq. of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC·HCl) in DMF at room temperature for 8 h in satisfactory yields. The T_g of the polymer rose with decrease of the methylene chain length of the dicarboxylic acid. In the T_gs of the polymers from L-leucinol, even-odd effect was observed with increase of the methylene chain length of the dicarboxylic acid. The molecular rotation values of the polymers were constant except for the polymer from succinic acid, which showed the negatively largest one. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2925–2934, 1997     

Silicon amino acids

The existence and gas phase stability of silicon analogues of three natural amino acids (i.e., silicon glycine, silicon alanine, and silicon valine) belonging to the novel class of compounds termed silicon amino acids (SiAA) are investigated theoretically on the basis of ab initio QCISD/aug‐cc‐pVTZ and MP2/aug‐cc‐pVTZ calculations. All molecules studied (in their gas phase canonical forms) are structurally comparable to their proteinogenic counterparts (i.e., glycine, l ‐alanine, and l ‐valine) and capable of forming several structural isomers as such. These higher energy isomers are characterized by small relative energies (not exceeding 4 kcal mol⁻¹). The simulated IR spectra of the Si‐Gly, Si‐Ala, and Si‐Val global minima are also presented and discussed.     

Synthesis and characterization of supramolecular optically active bisamides derived from amino acids

The synthesis and phase transitional behaviour of three pairs of enantiomeric supramolecular hexacatenar liquid crystals (LCs) derived from natural α-amino acids such as l/d-alanine, l/d-leucine and l/d-valine are described. Their preparation with high enantiomeric purity was accomplished by condensing optically active (amino acid residue containing) trialkoxy amines with a 3,4,5-trialkoxy cinnamic acid core using a peptide coupling reagent namely, 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyl-uronium hexafluorophosphate (HBTU). The mesomorphic behaviour of these self-complementing mesogens was ascertained by polarising optical microscopy, differential scanning calorimetry and X-ray diffraction. The compounds exhibit columnar (Col) phase over a wide thermal range. Particularly, a pair of enantiomers derived from l/d-leucine residues notably stabilize hexagonal Col (Col_h) phase over a wide temperature range of ?5 °C to 180 °C. Circular dichroism (CD) and FTIR studies suggest the chiral (helical) organization of mesogens within the columns through intermolecular hydrogen bonding; thus, these enantiomers represent one of the rarely reported examples of LCs exhibiting supramolecular Col_h phase at room temperature. The gelation studies reveal the ability of these bisamides to form stable supramolecular gels in ethanol caused through H-bonding interactions.