(2S)-(+)-2-溴-1-(6'-甲氧基-2'-萘基)丙-1-酮的不对称合成

以(2R,3R)-酒石酸二甲酯为手性辅助剂,6-甲氧基-2-丙酰基萘经缩酮化、溴化铜不对称溴化、水解等反应合成了(2S)-2-溴-1-(6'-甲氧基-2'-萘基)丙-1-酮。总收率94%。     

酒石酸酯固载薄层色谱法拆分盐酸克伦特罗对映异构体

药物对映体的各个单体通常具有不同的生物活性、药理活性,所以需要对它们进行拆分以得到旋光单体。D-和L-酒石酸是廉价的手性原料,（2R,3R）-酒石酸可直接从自然界获取。选择酒石酸衍生物例如酒石酸二酯、酒石酸单酰胺、酒石酸二酰胺等用于对映体拆分,效果比较令人满意。本工作将（2R,3R）-酒石酸-二环己酯固载在硅胶GF254板上,成功地拆分了盐酸克伦特罗对映体,并对其拆分机理进行了探讨。     

手性γ-氨基酸:5-羟基-3-氨基环己基甲酸的不对称合成

以光学纯的(1S,5S)-5-叔丁氧羰基氨基-3-环己烯基甲酸为原料,经立体选择性地碘代内酯化、脱碘、醇解、水解、酯化5步反应首次合成了两个光学纯的γ-氨基酸衍生物——(1R,3S,5R)-5-羟基-3-叔丁氧羰基氨基环己基甲酸甲酯(总收率36.7%)和(1R,3S,5R)-5-羟基-3-叔丁氧羰基氨基环己基甲酸苄酯(总收率35.2%),其结构经1H NMR,13C NMR,IR和ESI-HR-MS确证。     

新型C2轴对称吡啶羧酸酯手性多齿配体的合成

以L-(+)-酒石酸和吡啶甲酸为原料,经酯化,缩合、还原、DCC-DMAP催化酯化等反应合成了3个新型手性多齿配体--(4R,5R)-1,3-二氧戊环-2-苯基-4,5-二吡啶羧酸酯(5a～5c),其结构经1H NMR,13C NMR,IR和MS表征,并通过高斯软件HF/6-31G模拟了5a可能的分子结构.     

非甾体消炎药萘普生不对称合成研究

萘普生[(S)-(+)-S-(6'-甲氧基-2'-萘基)丙酸]是一种非常重要的非甾体消炎镇痛药。以(2R,3R)-酒石酸二甲酯为手性辅助剂,2-甲氧基萘经溴代、丙酰化、缩酮化、不对称溴化、水解、立体专一性重排和催化氢转移氢解等反应合成了光学活性萘普生,化学收率44%。制备的萘普生的光学纯度([α]~D^2^5=+63.5ⅲ)符合中华人民共和国药典(1995年版)的要求。     

草酸单乙酯三尖杉碱酯的合成及其在三尖杉酯类生物碱合成中的应用

用醇钠催化的酯交换方法合成了草酸单乙酯三尖杉碱酯(4),并用4和格氏试剂反应,得到合成三尖杉酯类生物碱的关键中间体α-酮酰基三尖杉碱(2),简化了已报道的一些三尖杉酯类生物碱的合成方法。     

手性酒石酸酯对不对称环氧化反应动力学拆分DL-1-十四烯-3-醇的催化选择性

利用Sharpless不对称环氧化反应动力学拆分二级烯丙醇DL-1-十四烯-3-醇,研究了不同手性酒石酸酯催化剂[酒石酸乙酯(DET)、酒石酸异丙酯(DIPT)、酒石酸环己酯(DCHT)以及酒石酸环十二酯(DCDT)]对该反应的催化选择性,拆分所得的烯丙醇的光学纯度有一定差异,从90%到99?.     

酒石酸酯立体选择性萃取分离功夫菊酸对映体

研究了功夫菊酸对映体在含有手性选择剂酒石酸酯的水-有机相双相体系中的萃取分配行为,考察了水相的pH、酒石酸酯的浓度、磷酸盐浓度、温度和酒石酸酯烷基链长度对分配系数(K)和分离因子(α)的影响.研究结果表明:分配系数(K)随pH的升高而降低,随着酒石酸酯浓度的增大而增大,分离因子(α)随pH的升高和酒石酸酯浓度的增大先增加后降低,pH和酒石酸酯浓度分别为5.50和0.30 mol/L时取得较好的分离效果;分配系数(K)和分离因子(α)都随磷酸盐浓度增大而减小;温度、取代烷基链长对分配系数(K)和分离因子(α)亦有较大影响.     

(R)-N-(β-三氯锗取代丙酰基)TTCA酯的合成及其倍半氧化物

β-三氯锗取代丙酰氯1a～1c与(R)TTCA酯反应, 得到光学活性的(R)-N-(β-三氯锗取代丙酰基)TTCA酯3a～3d([α]D^2^0-86.00～-94.35ⅲ)及光学活性的β-三氯锗取代丙酰氯2a～2d。化合物3a～3d经水解得到(R)-N-(β-取代丙酰基)TTCA酯基锗倍半氧化物4a～4d, [α]D^2^0-44.48～-77.00ⅲ。用半经验量子化学MNDO方法研究了反应物和产物最优构型的电子结构及反应的焓变。     

金属胶束催化对硝基苯酚吡啶甲酸酯水解的动力学研究

合成了两种大环过渡金属配合物NiR和CuR(R表示高氯酸-5,7,7,12,14,14-六甲基-1,4,8,11-四氮杂环十四烷),将NiR和CuR分别与表面活性剂正月桂酸肌氨酸组成金属胶束,并以其为模拟水解金属酶用于催化对硝基苯酚吡啶甲酸酯(PNPP)水解.特征光谱分析表明,在催化PNPP水解过程中形成了由Ni(Ⅱ)或Cu(Ⅱ)配合物与PNPP组成的中间物种,并由此提出了催化PNPP水解的机理,建立了用于计算动力学常数的动力学模型.     

R 和 s-1-(3'-溴-4'-甲氧基)苄基-2-甲基-6-甲氧基-7-羟基-1, 2,3,4-四氢异喹啉的合成

本文报道了R和S-1-(3'-溴-4'-甲氧基)苄基-2-甲基-6-甲氧基-7-羟基-1,2,3,4-四氢异喹啉的合成。     

(+)-Colletodiol : Synthesis from (S,S)-tartaric acid and (R)-3-hydroxy-butyric acid

E-(R)-5-Hydroxy-2-hexenoic acid (4) and the acetonide of E-(4R,5R,7R)-trihydroxy-2-octenoic acid (3) are joined to give, after deprotection, (+)-colletodiol (1). The syntheses of the two hydroxy-acids from poly-(R)-3-hydroxy-butanoate (PHB) and (?)-tartaric acid, respectively, are outlined.     

鼠味草植物中新的缩酚酸

从S.cavaleriei中分离了鼠味草酸I,用部分合成法证实了单阿魏酰基-R,R-(+)-酒石酸的绝对构型.     

Improvement of the Production Efficiency of l-(+)-Tartaric Acid by Heterogeneous Whole-Cell Bioconversion

An Escherichia coli-engineered bacterium with cis-epoxysuccinate hydrolase (ESH) activity was used to catalyze the stereospecific hydrolysis of cis-epoxysuccinic acid to l-(+)-tartaric acid. The effect of the substrate composition on the production efficiency of l-(+)-tartaric acid was investigated. Based on the sodium-type homogeneous substrate system, a heterogeneous substrate system, composed of 1.2 M sodium-type substrate and 1.8 M calcium-type substrate, was designed to improve ESH catalytic efficiency. After process optimization, a catalytic efficiency of 9.37?×?10^?3 g U^?1 h^?1 was obtained with fed-batch mode in the heterogeneous substrate system, about a twofold increase compared to the traditional bioconversion process with Nocardia tartaricans cells. The scale-up tests were carried out in a 15-m³ stirred tank reactor, which indicated that the heterogeneous substrate system had great application prospect for the l-(+)-tartaric acid industrial production.     

Stereoselective total synthesis and absolute configuration of the natural decanolides (-)-microcarpalide and (+)-lethaloxin. Identity of (+)-lethaloxin and (+)-pinolidoxin

[reaction: see text] Convergent, stereoselective syntheses of the pharmacologically active, naturally occurring lactones (-)-microcarpalide and (+)-lethaloxin have been achieved from the commercially available, chiral reagents (R)-glycidol, (S,S)-tartaric acid, and d-ribose as the starting materials. These syntheses have further served to establish the hitherto unknown absolute configuration of (+)-lethaloxin and to show its identity with (+)-pinolidoxin.     

Novel resolution of the anthracyclinone intermediate by the use of (2r, 3r)-(+)- and (2s, 3s)-(-).1,4-bis(4-chlorobenzyloxy)butane-2,3-diol: a simple and efficient synthesis of optically pure 4-demethoxydaunomycinone and 4-demethoxyadriamycinone

(±)-7-Deoxy-4-demethoxydaunomycinone((±)-3) was found to be cleanly resolved by forming a mixture of the diastereomereic acetals((-)-9and(+)-10 or(+)-9 and(-)-10)with the title vicinal-diol(+)-or ( )-5), affording optically pure (R)-( )-3. The resolving agents (( + )- and ( )-5) were readily synthesized from unnatural(2S,3S)-(-)-tartaric acid((-)-6)or D-(-)-mannitol and natural (2R,3R)-(+)-tartaric acid((+)6), respectively. The undesired enantiomer ((S)-(+ )-3) obtained by the optical resolution could be racemized by heating with trifluoromethanesulfonic acid in aq acetic acid. Optically pure (R)-3 was elaborated to optically pure (+)-4-demethoxydaunomycinone ((+)-2b) and (+)-demethoxyadriamycinone ((+)-2a) by featuring highly stereoselective ( ? 20:1) introduction of the OH group into the C₇-position as a key step.     

Revision of absolute configuration of enantiomeric (methylenecyclopropyl)carbinols obtained from (R)-(-)- and (S)-(+)-epichlorohydrin and methylenetriphenylphosphorane. Implications for reaction mechanism and improved synthesis of antiviral methylenecyclopropane analogues of nucleosides

Absolute configurations of enantiomeric methylenecyclopropanecarbinols obtained by reaction of (R)- and (S)-epichlorohydrin 5 with methylenetriphenylphosphorane or resolution of the corresponding oxaphospholane 6 via a salt with L-(+)-tartaric acid and subsequent Wittig transformation with formaldehyde were revised. The (-)-oxaphospholane 6 has the S,S and (-)-(methylenecyclopropyl)carbinol (4) the R configuration. The configurations of (+)-6 and (+)-4 are then R,R and S, respectively. These assignments are in accord with an initial attack of phosphorane at the oxirane ring of epichlorohydrin. An improved preparation of key enantiomeric intermediates (R)-1a and (S)-1a, important for synthesis of antiviral purine methylenecyclopropane analogues of nucleosides, is also described.     

Synthesis and absolute configuration of the enantiomers α-aminoethylcymantrene and some of its derivatives

Resolution of α-aminoethylcymantrene (I) to its enantiomers has been effected for the first time by means of (+)-d-tartaric acid. The molecular structure and absolute configuration of (+)-(R)-α-(N-acetylamino)ethylcymantrene prepared from ()-I have been established by an X-ray analysis. On the basis of chemical and chiroptical correlation methods the R-configuration of the chiral centre is also assigned to ()-I, (+)-α-(N,N-dimethylamino)ethylcymantrene, (+)-II, and (+)-α-(N,N,N-trimethylammonium)ethylcymantrene iodide, (+)-III. ORD and CD curves of the prepared optically active compounds have been studied     

Preparation and characterization of Co(II), Ni(II) and Cu(II) complexes of a ligand containing 1,3,4-thiadiazole groups

(1R,2R)-1,2-bis-(5-amino-1,3,4-thiadiazole-2-yl)ethane-1,2-diol (L) has been prepared by the reaction of thiosemicarbazide with (2R,3R)-(+)-tartaric acid (I) and phosphorous oxychloride, and its complexes with Co(II), Ni(II) and Cu(II) have been obtained. The structures of the ligand and its complexes have been established by i. r., ¹H- and ¹³C-n.m.r. spectra, u.v.–vis–nir spectroscopy, elemental analyses, T.g.-D.t.a. and magnetic susceptibility measurements.     

Synthesis of Novel Tartaric Acid-derived Chiral Phosphite Ligands and Their Application in the Cu-catalyzed Conjugate Addition of Diethylzinc to Cyclic Enones

Five novel tropos (3R,4R)- and/or (3S,4S)-N-benzyltartarimide-derived biphenylphosphite ligands were synthesized and applied in the Cu-catalyzed asymmetric conjugate addition of diethylzinc to cyclic enones with up to 75% e.e. Compared with the reported ligand 1-N-benzylpyrrolidine-3,4-bis[(R)-1,1'-binaphthyl-2,2'-diyl]phosphite-L-tartaric acid, the issue that L-(+)-tartaric acid backbone and (R)-binaphthyl showed strong matched/mismatched character was solved with these tropos ligands. It was found that the enantioselectivity was mainly controlled by the absolute configuration of N-benzyltartarimide backbone, and both enantiomers of the addition products can be obtained by simply changing the configuration of N-benzyltartarimide substituent.