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1.
以(S)-布洛芬为拆分剂,对(R,S)-2-(1,6,7,8-四氢-2H-茚并[5,4-b]呋喃-8-基)乙胺进行拆分,获得雷美替胺的关键中间体(S)-2-(1,6,7,8-四氢-2H-茚并[5,4-b]呋喃-8-基)乙胺,ee值99%,总收率60%,其结构经1H NMR和HR-MS(ESI)确证。  相似文献   

2.
黄志雄  吴成龙  桑志培  邓勇 《有机化学》2012,32(12):2368-2372
发展了一条1,2,6,7-四氢-8H-茚并[5,4-b]呋喃-8-酮的新合成方法,以价廉、易得的对溴苯酚为原料,在无水碳酸钾作用下与2-溴乙醛缩二乙醇缩合后用多聚磷酸(PPA)环合得5-溴苯并呋喃,该中间体与丙烯酸甲酯在Pd(OAc)2催化下,经Heck偶合反应得3-(苯并呋喃-5-基)丙酸甲酯,在氢氧化钠水溶液中经Raney Ni催化氢化和水解一锅反应得3-(2,3-二氢苯并呋喃-5-基)丙酸,再经二溴代、Friedel-Crafts酰化反应和氢解脱溴,得1,2,6,7-四氢-8H-茚并[5,4-b]呋喃-8-酮,7步反应总收率49.9%.该方法原料易得、反应条件温和、操作简便、产物分离纯化容易,收率良好,适合大规模制备1,2,6,7-四氢-8H-茚并[5,4-b]呋喃-8-酮.  相似文献   

3.
利用非对映异构体盐在溶剂中溶解度的不同,以(1S,2R)-1-氨基-2-茚醇(1)为手性拆分剂,拆分四氢糠酸[(RS)-THFA, (RS)-2]获得高光学纯的(S)-2,其结构经1H NMR, 13C NMR和HPLC确证。探究了不同溶剂量和投料比对拆分效果的影响。结果表明较佳拆分条件为:以4-甲基-2-戊酮(3)作溶剂,n[(RS)-2]: n(1)=2.2 : 1,一次拆分得91.7% ee (S)-2;再以n[91.7% ee (S)-2]: n(1)=6 : 5进行二次拆分得99.0% ee (S)-2。拆分剂的回收率提高至92.0%,同时对拆分母液中的非目标对映体成功地进行消旋化,回收率为89.0%,实现了四氢糠酸的循环拆分。  相似文献   

4.
脱氢松香胺是由天然松香酸经脱氢、胺化反应而合成的一种三环二萜基胺[1],是一种光活性化合物.常用作外消旋体的光学拆分剂. 本文将脱氢松香胺作为手性诱导物,与顺-1,3-二苄基-四氢-4H-呋喃并[3,4-d]咪唑-2,4,6-三酮经缩合、高立体选择性还原、水解得到内酯(-)-(3aS,6aR)-1,3-二苯基-四氢-4H-呋喃并[3,4-d]-咪唑-2,6(1H)-二酮[2].收率达70%,而ee值高达91%.  相似文献   

5.
Eight chiral vinylterphenyl monomers,(+)-2,5-bis{4′-[(S)-1″-methylpropyloxy]phenyl}styrene(Ia),(+)-2,5-bis{4′-[(S)-2″-methylbutyloxy]phenyl}styrene(Ib),(+)-2,5-bis{4′-[(S)-3″-methylpentyloxy]phenyl}styrene(Ic),(+)-2,5-bis{4′-[(S)-4″-methylhexyloxy]phenyl}styrene(Id),(?)-2,5-bis{4′-[(R)-1″-methylpropyloxy]phenyl}styrene(Ie),(+)-2-{4′-[(S)-1″-methylpropyloxy]phenyl}-5-{4′-[(R)-1″-methylpropyloxy]phenyl}styrene(IIa),(?)-2-{4′-[(R)-1″-methylpropyloxy]phenyl}-5-{4′-[(S)-1″-methylpropyloxy]phenyl}styrene(IIb),and(+)-2-{4′-[(S)-2′′-methylbutyloxy]phenyl}-5-{4′-[(S)-1″-methylpropyloxy]phenyl}styrene(III),were synthesized and radically polymerized.These molecules were designed to further understand long-range chirality transfer in radical polymerization and to possibly tune the chiroptical properties of the polymers by varying the spatial configuration,position,and various combination of the stereogenic centers at the ends of p-terphenyl pendants.The resultant polymers adopted helical conformations with a predominant screw sense.When the stereogenic centers ran away from the terphenyl group as in Ib?d,the corresponding polymers changed the direction of optical rotation in an alternative way and showed no obvious stereomutation upon annealing in tetrahydrofuran.The two stereogenic centers of IIa,IIb,and III acted concertedly in chiral induction,whereas those of Ia and Ie played a counteractive role.The five polymers derived from Ia,Ie,IIa,IIb,and III underwent stereomutation when annealed in tetrahydrofuran.The polymers PIa?e had good thermal stability and high glass transition temperatures(Tgs).They generated liquid crystalline phases at above Tgs that could be kept upon cooling,with the exception of PIe.This result was consistent with the extended helical structures.  相似文献   

6.
从色醇出发,通过Sharpless环氧化、酰胺化、偶联和成盐四步反应合成了一系列新型的吲哚并四氢呋喃-咪唑盐杂合物,其结构经~1H NMR,~(13)CNMR,HRMS以及X射线单晶衍射确定.对合成的新化合物进行了体外抗肿瘤细胞毒活性筛选,结果表明,1-((3aR,8aS)-3,3a-二氢-3a-羟基-2H-呋喃并[2,3-b]吲哚-8(8aH)-基)乙酮-3-(2-(萘-2-基)-2-氧乙基)-5,6-二甲基-1H-苯并[d]咪唑-3-溴盐(20)和1-((3aR,8aS)-3,3a-二氢-3a-羟基-2H-呋喃并[2,3-b]吲哚-8(8aH)-基)乙酮-3-(2-萘甲基))-5,6-二甲基-1H-苯并[d]咪唑-3-溴盐(22)具有较好的体外肿瘤生长抑制活性,对SMMC-7721、MCF-7和SW-480肿瘤细胞株的活性均优于顺铂(DDP),1-((3aR,8aS)-3,3a-二氢-3a-羟基-2H-呋喃并[2,3-b]吲哚-8(8a H)-基)乙酮-3-(2-溴苄基))-5,6-二甲基-1H-苯并[d]咪唑-3-溴盐(24)对SW-480肿瘤细胞株表现出较好的选择性细胞毒活性,其IC_(50)值约为顺铂的2.0倍.  相似文献   

7.
手性螺硼酸酯(R)-或(S)-1,1'-联-2-萘酚硼酸-(S)-脯氨酸酐[(R,S)-1或(S,S)-1]对前手性亚胺硼烷还原的不对称催化活性被观察到.在(R,S)-1或(S,S)-1存在下,由前手性二烷基酮或烷基苯酮与苯胺缩合生成的前手性亚胺在THF中被硼烷还原,高产率地给出手性仲胺,其对映体纯度高达74% ee.其中,三种手性仲胺[N-(2-戊基)苯胺,N-(3-甲基-2-丁基)苯胺和N-(4-甲基-2-戊基)苯胺]系首次合成.  相似文献   

8.
在无催化剂的条件下,以醛、3-甲基-1-苯基-1H-吡唑-5-胺和1,3-茚二酮为原料,通过水相中微波促进下的多组分反应,成功地实现了具有重要生物意义的茚并[2,1-e]吡唑并[5,4-b]吡啶的绿色合成。这种方法具有环境友好、反应时间短、产率高、价廉、操作简单以及广泛的适用范围等显著优点。  相似文献   

9.
以2,3-二甲基吡啶为起始原料, 经过11步反应, 不对称合成了质子泵抑制剂的关键中间体: (R)-2-{[4-(3-甲氧基丙氧基)-3-甲基吡啶-2-基]甲基亚硫酰基}-1H-苯并咪唑. 研究了用手性高效液相色谱拆分对映体、测定产品光学纯度的方法, 结果表明目标产品的ee值达到99%. 通过IR, UV, MS以及1H NMR分析对重要中间体和目标产品进行了结构鉴定.  相似文献   

10.
龙凌亮  王林  吴燕俊 《合成化学》2015,23(1):13-16,22
以2,3-丁二酮为原料,依次与苯甲醛和对苯二甲醛经缩合反应制得4-{4,5-二[(E)-苯乙烯]-1H-咪唑-2-基)苯甲醛}(2);以对二氯苄作为连接链,2与其经取代反应制得4-{1-[4-(氯甲基)苄基]-4,5-二[(E)-苯乙烯]-1H-咪唑-2-基}苯甲醛(3);3与单羟基四苯基卟啉(4)连接合成了4-{4,5-二[(E)-苯乙烯]-1H-咪唑-2-基}苯甲醛共价键连单羟基四苯基卟啉化合物(5),其中2,3和5为新化合物,其结构经1H NMR,MS和元素分析表征。用荧光光谱研究了5中基团3与基团4之间的能量转移过程。结果表明,当激发取代基团3时,能量能够从基团3转移至基团4上。  相似文献   

11.
我们发展了酸催化的二芳基甲醇的脱水环化氧化芳构化的方法,直接高产率(高达81%)的合成轴手性的4-芳基喹啉.而且,LewisZnOTf2和手性膦酸都能催化这个反应,初步的不对称研究可以用er 71:29得到产物.  相似文献   

12.
手性固定相(chiral stationary phase,CSP)作为手性色谱分离的核心技术,在手性化合物的识别和分离中得到广泛应用。以双手性选择单元结合作为CSP是近些年的研究热点,研究表明,两种手性选择单元相结合的CSP可增加手性识别位点,显著提高分离效果。本文介绍了近几年双手性选择单元手性固定相在手性分离中的研究进展,并对其发展前景进行了展望。  相似文献   

13.
The field of chiral separations had a modest beginning some two decades ago. However, due to rapid technological advancement coupled with simultaneous availability of innovative chiral stationary phases and novel chiral derivatization agents, the field of chiral separations has now totally outpaced many other separation fields. Keeping pace with rapid changes in the field of chiral separations, investigators continue to add stereoselective pharmacokinetic, pharmacodynamic, pharmacologic and toxicological data of new and/or marketed racemic compounds to the literature. Examination of the evolution of chiral separations suggests that in the beginning many investigators attempted to separate and quantify a single pair of enantiomers, adopting either direct (separation made on a chiral stationary phase) or indirect (separation made following precolumn conversion of enantiomers to corresponding diastereomers) approaches. However, more recent trends in chiral separations suggest that investigators are attempting to separate and quantify multiple pairs of enantiomers with available technologies. Added to this, some interesting trends have been observed in many of the recently reported chiral applications, including preferences regarding internal standard selection, mobile phase contents and composition, sorting out issues with mass spectrometric detection, determination of elution order, analytical manipulations of metabolite(s) without reference standards and addressing some specificity-related issues. This review mainly focuses on chiral separations involving multiple chiral analytes and attempts to justify the need for such chiral separations involving multiple analytes. In this context, several cases studies are described on the utility and applicability of such chiral separations under discrete headings to provide an account to the readership on the implications of such tasks. The topics of case studies covered in this review include: (a) therapy markers--differentiation from drug abuse and/or applicability in forensics; (b) role in pharmacogenetic/polymorphic evaluation; (c) monitoring and understanding the role of parent and active metabolite(s) in clinical and preclinical investigations; (d) exploration on the pharmacokinetic utility of an active chiral metabolite vis-a-vis the racemic parent moiety; (e) understanding the chirality play in delineating peculiar toxic effects; (f) exploration of chiral inversion phenomenon, and understanding the role of stereoselective metabolism. For the further benefit of readership, some select examples (n = 19) of the separation of multiple chiral analytes with appropriate information on chromatography, detection system, validation parameters and applicable conclusion are also provided. Finally, the review covers some useful considerations for method development involving multiple chiral analytes.  相似文献   

14.
15.
采用高效液相色谱法,在自制的纤维素-三(3,5-二甲基苯基氨基甲酸酯)(ATEO-OD)、纤维素-三(4-甲基苯基氨基甲酸酯)(ATEO-OG)和纤维素-三(4-甲基苯基甲酸酯)(ATEO-OJ)3种手性柱上对16种不同结构的手性化合物进行了拆分和比较.试验结果表明:16个手性样品在这3种手性固定相上分别获得了不同程度的拆分,A TEO-OD对所分析样品具有更好的手性识别能力,ATEO-OG和ATEO-OJ的手性识别能力相当.  相似文献   

16.
Chiral ligand‐exchange chromatography is one of the elective strategies for the direct enantioresolution of small chelating compounds: amino acids, diamines, amino alcohols, diols, small peptides, etc. Unlike other methods, the interaction between chiral selector and analyte enantiomers is mediated by a cation, thus producing diastereomeric ternary complexes. Two main approaches are conventionally applied in chiral ligand‐exchange chromatography. The first relies upon chiral stationary phases where the chiral selector is either covalently immobilized or physically adsorbed onto suitable packing materials (coated phases). In the second approach, chiral molecules are added to the eluent, thus generating chiral eluent systems. Among the advantages of chiral ligand‐exchange chromatography, the generation of UV/vis‐active metal complexes, and the use of commercially available or easy‐to‐synthesize chiral selectors, in combination to rather inexpensive achiral columns for coated phases and chiral eluents, are noteworthy. Besides amino acids and amino alcohols, other species have proven suitable for chiral ligand‐exchange chromatography applications. Recently, the use of either chiral ionic liquids or micellar liquid chromatography systems as well as the successful off‐column formation of diastereomeric complexes have expanded the selectivity profiles and application fields. All of these issues are touched in the review, shedding light to the contributions appeared in the last decade.  相似文献   

17.
张蓉平  黄一鹤  范荣华  周励 《化学通报》2023,86(9):1078-1083
手性污染物对映体尽管具有相似的物理化学性质,但在环境中的吸附、转移、降解等过程往往存在一定差异。生态安全问题与人类健康密切相关,因此,对手性环境污染物进行对映体水平上的分离分析是十分重要的研究课题。目前,国内外对环境中的手性污染物已开展了相关研究,然而全面评述相关分析测定方法的新进展鲜有报道。本文主要对环境中手性污染物的种类以及近5年环境中手性污染物的分析检测技术如液相色谱-质谱联用法、气相色谱-质谱联用法、毛细管电泳法、超临界流体色谱-质谱联用法等进行了归纳、综述和展望,为后续手性污染物的分析检测提供依据和参考。  相似文献   

18.
手性2-噁唑烷酮的无溶剂合成法;手性氨基醇;脲;手性噁唑烷酮  相似文献   

19.
Chiral compounds are very important in drug development, organic synthesis, materials science, toxicology, or environmental chemistry. Therefore, for creating new drugs, several methods have been suggested in recent years. In several laboratories in the world, some new methods for the derivations of the parameters were constructed and used for studies on quantitative structure–activity/property relationships of chiral molecules. The algorithms reviewed in this paper involve Zargeb group chiral indices, chiral molecular connectivity index, chiral topological charge index, chiral Am index, chiral indices based on the matrixes, chiral indices based on chiral product, conformation‐independent chirality code, conformation‐dependent chirality code, quantitative two‐dimensional chirality degrees of benzenoids, and so on. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

20.
在无溶剂条件下,手性的β-氨基醇和脲在160-180℃反应0.5-1 h,在200℃反应0.5 h,高产率地获得手性噁唑烷酮。  相似文献   

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