共查询到18条相似文献,搜索用时 187 毫秒
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(1S,3R)-樟脑酸酐由(1R,3S)-樟脑酸制得并经过元素分析、红外光谱、比旋光度和X-射线单晶衍射表征。通过晶体结构和量子化学计算的结果对该化合物中两个手性碳原子同时发生构型翻转进行了讨论。(1S,3R)-樟脑酸酐的晶体学数据:正交晶系,空间群为P2(1)2(1)2(1),a=0 64872(15)nm,b=1 1190(3)nm,c=1 3010(3)nm,V=0 9444(4)nm3,Z=4,Dc=1 282Mg·m-3,Rint=0 0555,S=1 001,I>2σ(I)data:R1=0 0454,wR2=0 0927,alldata:R1=0 0588,wR2=0 0959。 相似文献
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以乙酰基二茂铁为原料,经过钯催化氢化胺化及(R)-(+)-酒石酸拆分制备了(R)-1-二茂铁基乙基二甲胺(Ⅲ);Ⅲ与正丁基锂作用后,与二苯基氯化膦作用得到N,N-二甲基-(R)-1-[(S)-2-(二苯基膦)二茂铁基]乙胺(Ⅳ);Ⅳ与新制的二(3,5-二甲基苯基)膦烷发生构型保持的取代反应,得到双膦配体(R)-1-[(S)-2-(二苯基膦)二茂铁基]乙基二(3,5-二甲基苯基)膦(Ⅷ)。以乙酰基二茂铁计Ⅷ的总收率达19.5%,手性高效液相色谱分析其ee值达95%。 相似文献
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Marek Krl Grzegorz
lifirski Jerzy Kleps Piotr Podsadni Ilona Materek Anna E. Kozio Franciszek Herold 《International journal of molecular sciences》2023,24(1)
This article describes the synthesis of new chiral 3-(piperidin-3-yl)-1H-indole derivatives (R)-10a-c and (S)-11a-c from the corresponding diastereomers: (3R, 2R) and (3S, 2R)-2-[3-(1H-indol-3-yl)-1-piperidyl]-2-phenyl-acetamides (3R, 2R)-4a, (3R, 2R)-6b, (3R, 2R)-8c and (3S, 2R)-5a, (3S, 2R)-7b, (3S, 2R)-9c. Diastereomers were obtained by N-alkylation of derivatives of racemic 3-(piperidin-3-yl)-1H-indoles 1a-c using (S)-2-(4-toluenesulfonyloxy)-phenylacetic amide (S)–II. The same method was applied to obtain (3R, 2S)-methyl-2-[3-(1H-indole-3-yl)-1-piperidyl]-2-phenylacetate (3R, 2S)-2a and (3S, 2S)-methyl-2-[3-(1H-indole-3-yl)-1-piperidyl]-2-phenylacetate (3S, 2S)-3a diastereomers by treating amine 1a with (R)-2-(4-toluenesulfonyloxy)-phenylacetic acid methylester (R)-I. Systematic studies via single crystal X-ray crystallography were used to determine the molecular structure of the racemates 1a-c and the absolute configuration of the enantiomers. The solid racemates 1b and 1c were “true racemates” crystallizing in a centrosymmetric space group, while 1a formed a racemic conglomerate of homoenantiomeric crystals. The absolute configuration was determined for the enantiomeric pairs (R)-10a/(S)-11a, (R)-10b/(S)-11b, and (R)-12c/(S)-13c, as well as for (3S,2S)-3a. Spectra of 1H, 13CNMR, HPLC, and HRMS for diastereomers and enantiomers were consistent with the determined structures. 相似文献
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W. Werner D. Tresselt W. Ihn G. Ziebell 《Advanced Synthesis \u0026amp; Catalysis》1987,329(6):1031-1037
Resolution of the Enantiomers of (S,R)-1,1′-Bi-2,2′-naphthylhydrogenphosphate by (1R,2R)- and (1S,2S)-2-Amino-1-(4-nitrophenyl)-propane-1,3-diol The resolution of the diastereoisomeric salts of the title compounds was possible in the presence of a ketone, especially acetone, which forms oxazolidines ( 3a–d ) with the chiral bases. These oxazolidines afforded separable salts with the (S,R)-1,1′-Bi-2,2′-naphthylhydrogenphosphate ( 4 ). The structures of these salts were proved by m.s. and n.m.r. spectroscopy. 相似文献
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以1-乙基-3-(3-二甲胺丙基)碳二亚胺盐酸盐(EDCI)/1-羟基苯并三氮唑(HOBt)为缩合剂,5-氟尿嘧啶-1-基乙酸为中间体,分别与L-酪氨酸甲酯和D-酪氨酸乙酯通过液相偶联合成了(S)-2-(2-(5-氟-2,4-二氧-3,4-二氢嘧啶-1(2H)-基)乙酰氨基)-3-(4-羟苯基)丙酸甲酯和(R)-2-(2-(5-氟-2,4-二氧-3,4-二氢嘧啶-1(2H)-基)乙酰氨基)-3-(4-羟苯基)丙酸乙酯,水解后得到相应的酸对映体。所合成的化合物结构经1H NMR1、3C NMRI、R、MS及比旋光度等测试得以确证。四种化合物的体外抗肿瘤活性测试结果,说明该化合物的抗肿瘤具有一定的选择性,且R构型对抗肿瘤也起到了一定的作用。 相似文献
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医药中间体(3R,4R)-3-[(1R)叔丁基二甲基硅氧乙基]-4-乙酰氧基-2-氮杂环丁酮的合成 总被引:1,自引:0,他引:1
以6-氨基青霉烷酸(6-APA)为原料经重氮化、溴化、酯化、还原、开环、氧化反应得到目标产物医药中间体(3R,4R)-3-[(1R)叔丁基二甲基硅氧乙基]-4-乙酰氧基-2-氮杂环丁酮。经1H NMR,IR证明得到了氮杂环丁酮,提高了酯化反应的收率,改变了格氏试剂反应中苛刻的条件,降低了开环反应的温度并提高了开环收率,总收率为35.88%。 相似文献
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采用格氏试剂C6H13MgBr和C10H2MgBr对光学活性O-TMS保护的(R)-氰醇的氰基加成,随之用NaBH4对亚胺化合物立体诱导还原氢化,以98%的de值合成了两个新的手性试剂(1R,2S)-2-氨基醇,产率分别达到59%和62%.并通过X射线单晶结构分析法测定了分子结构和晶体结构. 相似文献