关键词： asymmetric synthesis   nitrogen heterocycles   N-acyliminium ions   PCP site ligands   pharmacological enantioselectivity  

摘要： A new method for the asymmetric synthesis of 1-substituted tetrahydroisoquinolines is presented. It is based on stereoselective addition reactions of organometallic compounds to the intermediate N-acyliminium ion 6, which is provided with an N-acyl group as a chiral auxiliary. In addition reactions with organomagnesium and organozinc reagents diastereoselectivities from 70:30 to 95:5 (for 7/8) were observed with the zinc reagents in general leading to markedly improved stereoselectivities. By catalytic hydrogenation of 7 and 8 and after removal of the chiral auxiliary the target compounds 11 and 12 were obtained. The enantiomerically pure 11c-g and 12c-g (ee > 99 %), 1-aryl-tetrahydroisoquinolines, were evaluated for their affinity to the PCP [1-(1-phenylcyclohexyl)piperidine] binding site of the NMDA (N-methyl D-aspartate) receptor. In each case the enantiomers 11 exhibited a higher affinity than those of 12, with the potencies of the enantiomers differing by a factor of 4 (11/12g) to 27 (11/12c). The absolute configuration of the more potent enantiomers 11 is in accordance with the stereochemical requirement found for FR 115427 (3) which is a close analogue.

关键词： Ligands   Genetics   Phosphorus   Addition reactions   Molecular structure  

摘要： The organopalladium complex containing ortho-metalated (S)-( 1-(dimethylamino)ethyl)naphthalene as the chiral auxiliary has been used successfully to promote the asymmetric [4 + 2] Diels-Alder reaction between 3,4-dimethyl-1-phenylphosphole and 2-vinylpyridine. The pyridyl group in the resulting phosphanorbornene cycloadducts can be located stereospecifically in the exo or endo position by controlling the electronic properties of the organopalladium promoter. In the exo-cycloaddition process, the P-N bidentate ligand (-)-2-[(1 alpha,2 alpha(S),4 alpha,7S)-5,6-dimethyl-7-phenyl-7-phosphabicyclp[2.2.1]hept-5-ene-2-yl]pyridine was produced stereoselectively. In the endo-cycloaddition process, however, a pair of separable diastereomeric palladium template complexes containing the naphthylamine auxiliary and the enantiomeric forms of 2-[(1 alpha,2 beta(R/S),4 alpha,7(R/S)-5,6-dimethyl-7-phenyl-7-phosphabicyclo-[2.2.1]hept-5-ene-2-yl]pyridine were obtained. In these diastereomeric complexes, the endo-cycloadducts coordinated on palladiun as monodentate ligands via only their phosphorus donor atoms. The pyridyl-nitrogen atoms are not involved in metal complexation. The absolute configurations and the coordination properties of the exo- and endo-pyridylphosphines have been established by single-crystal X-ray analyses.

关键词： Group 14 compounds   Carbene complexes   Inorganic compounds   Stereochemistry   Molecular structure  

摘要： Chiral silanes and stannanes can be obtained with high optical purity from the 1,1-addition reactions of nonchiral silanes and stannanes With Fischer carbene complexes substituted with a chiral imidazolidinone auxiliary. The alpha-stannyl imidazolidinone products will undergo transmetalation and alkylation with, high stereoselection with reactive electrophiles.

关键词： 聚合物试剂   手性试剂   有机合成   不对称合成   合成  

摘要： 聚合物支载的有机合成反应比相应的小分子合成体系有独特的优越性．我院有机化学研究室多年来在制备聚合物试剂和催化剂及其在有机合成反应中的应用进行了系统研究，并且在聚合物试剂和催化剂在不对称有机合成反应中的应用研究方面亦取得重要成果。

关键词： 有机金属试剂   不对称合成   手性试剂   手性催化剂  

摘要： 本文综述了有机金属试剂在不对称有机合成中的应用。介绍了应用手性试剂进行不对称有机合成，以及应用手性催化剂进行不对称合成的方法。

关键词： 不对称合成   晶体结构   螺环化合物   氧氮杂草二酮  

摘要： 利用手性源（2R，3S）－3，4-二甲基-2-苯基-1，4-氧氮杂-5,7-二酮（1）合成了具有光学活性的7，8-二甲基-3，6-二苯基-5-氧-8-氮螺[2．6]壬-4，9-二酮（3）．测定了化合物（3）的晶体结构，并讨论了在环加成反应中的不对称诱导作用的机理．

关键词： 6-(hydroxymethyl)piperidin-2-one   asymmetric dihydroxylation   1,4-bis(dihydroquininyl)anthraquinone   4-methoxyphenylmethyl   5,6-dihydroxyhexanoate   4-methoxyphenylmethylhex-5-enoate  

摘要： A practical asymmetric synthesis of both enantiomers of 6-(hydroxymethyl)piperidin-2-one 1 is described. Asymmetric dihydroxylation (AD) of alkenyl ester 2 using the (DHQ)(2)AQN ligand provides diol (5S)-3 in greater than or equal to 95% ee after recrystallisation. This diol can subsequently be transformed into (6R)-1 using a five step reaction sequence. By employing (DHQD)(2)AQN [1,4-bis(dihydroquininyl)anthraquinone] in the initial AD reaction, (6S)-1 can be prepared in an analogous fashion.

关键词： Enolates   Carbene complexes   Adducts   Molecular structure   Aldol reactions  

摘要： Versatile, efficient reagents for asymmetric synthesis can be generated in one step from alkoxy or acetoxy Fischer carbene complexes and the commercial chiral auxiliary 1,5-dimethyl-4-phenyl-2-imid...

关键词： 手性烷基α   糠胺   合成方法   天然产物   不对称合成  

摘要： 该论文的工作是先研究手性烷基α-糠胺的合成方法,然后利用它对非天然α-氨基酸、1-脱氧氮糖化合物、多取代哌啶类生物碱Desoxoprosphylline及1-Deoxycastanospermine进行了不对称合成研究.

关键词： 哥纳香醇甲   抗肿瘤活性   不对称合成  

摘要： 哥纳香醇甲（１）是从番荔枝科哥纳香属植物海南哥纳香的根和茎皮中分离得到的有明显抗肿瘤活性的化合物，本文以αＤ葡庚糖酸内酯为原料，经９步反应对其进行了不对称合成研究，总收率为１３３％。根据药物设计原理，设计合成了２６个类似物，并进行了抗肿瘤活性筛选，初步结果表明大部分化合物体外对多种瘤株有不同程度的抑制作用。