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本文报道了赤式苄基酒石酸甲乙酯(3)的立体选择性合成,其~1H核磁共振谱、红外光谱和质谱与预期的结构一致。这个方法对合成其它具有赤式酒石酸结构的天然产物有一定的参考价值。  相似文献   

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徐贤恭  谢周  刘伯发 《有机化学》1985,5(4):309-312
本文合成(2E,4Z)-4,5-二苯基-2,4-戊二烯醇,并分别与丙烯酰氯及顺丁烯二酸酐反应生成对应的酯。研究了丙烯酸-(2E,4Z)-4,5-二苯基-2,4-戊二烯酯和顺丁烯二酸-(2E,4Z)-4,5-苯基-2,4-戊二烯单酯的分子内Diels-Alder反应,并证实这两种酯分子内环加成反应的活性有很大差异。通过NMR,IR,MS,UV等图谱分析,并运用分子轨道理论,探讨了该环加成反应的过程及其区域专一性和立体选择性。  相似文献   

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糖基异硫氰酸酯的合成及其应用   总被引:5,自引:0,他引:5  
作为一类重要的有机合成中间体,糖基异硫氰酸酯广泛地应用于具有生理活性化合物的制备。本文对糖基异硫氰酸酯的结构、制备方法,以及作为中间体在糖基硫脲、糖基杂环、胍基糖苷、糖基缀合物等重要化合物的合成中的应用作了较详尽阐述。在对这些研究现状进行分析的基础上,对该研究领域下一步的发展方向提出了我们的观点。  相似文献   

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使用苯基果糖硫苷给体立体专一地合成α-D-呋喃果糖苷   总被引:1,自引:0,他引:1  
薛军  惠永正 《有机化学》1999,19(6):606-609
在果糖的合成研究中,合成了四苯甲酰基苯基果糖硫苷,并首次将其用作糖苷化反应的给体,在NIS(N-碘代丁二酰亚胺)/AgOTf(三氟甲磺酸银)的促进之下,与乙酰化保护的蔗糖受体反应,从而以高产率立体专一地合成了α构型的呋喃果糖苷。所有产物的构型均由^1HNMR和^1^3CNMR谱图加以证实。  相似文献   

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核苷研究(Ⅳ)──辛可芬三唑啉硫酮核苷的立体选择性合成陈宏明,张键,毛建民,蔡孟深(北京医科大学药学院有机教研室,北京,100083)关键词核苷,合成,立体选择性辛可芬(Cinchophen)早年作为镇痛药和抗炎症药曾被广泛应用于临床[1],由于它有...  相似文献   

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在KF存在下,3-氧化木糖与亲核试剂发生加成反应,立体选择性地合成了4个新型3-C-支链呋喃核糖衍生物(2~5,其中4用生物方法脱苯甲酰基保护得6),其结构经1H NMR, IR, HR-MS表征;2的绝对构型由X-射线单晶衍射分析确证.  相似文献   

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L-半胱氨酸盐酸盐与二硫化碳, 氢氧化钠在硝酸铅存在下进行成环反应得到(R)-四氢噻唑-2-硫酮-4-羧酸产率76% , 后者与 醇在硫酸铁水合物催化下反应得到(R)-四氢噻唑-2-硫酮-4-羧酸酯, 产率40~82% .  相似文献   

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2-Phenyl-1, 2, 3-triazole-4-formylhydrazine (2) was prepared by hydrazinolysis of the corresponding ester 1. Reaction of 2 with CS2/KOH gave the oxadiazole derivatives (3) which via Mannich reaction with different dialkyl amines furnished 3-N, N-dialkyl derivatives (4a–c). Also, condensation of 2 with appropriate aromatic acid in POCI3 yielded oxadiazole derivatives (5a–c), or with aldehydes and ketones afforded hydrazones (6a–c). Cyclization of (6a–c) with acetic anhydride gave the desired dihydroxadiazole derivatives (7a–c). On the other hand, reaction of dithiocarbazate (8) with hydrazine hydrate gave the corresponding triazole derivative (9) which on treatment with carboxylic acids in refluxing POCI3 yielded s-triazole [3, 4–b]-1, 3, 4-thiadiazole derivatives (10a–b). The structures of all the above compounds were confirmed by means of IR, 1H NMR, MS and elemental analysis.  相似文献   

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Reactions of 1-(5-methyl)-1H-1,2,3-triazol-4-yl)ethan-1-ones and benzaldehydes in ethanol under basic conditions gave the corresponding chalcones. Reactions of the chalcones combined with thiosemicarbazide in dry ethanol containing sodium hydroxide afforded the corresponding pyrazolin-N-thioamides. Reactions of the synthesized pyrazolin-N-thioamides and several ketones (namely, ethyl 2-chloro-3-oxobutanoate, 2-bromoacetylbenzofuran, and hydrazonoyl chloride) gave the corresponding novel 2-(1,2,3-triazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazoles in high yields (77–90%). Additionally, 2-(4,5-dihydro-1H-pyrazol-1-yl)-4-(1H-1,2,3-triazol-4-yl)thiazoles were obtained in high yields (84–87%) from reactions with N-pyrazoline-thioamides and 4-bromoacetyl-1,2,3-triazoles under basic conditions. The structures of six of the newly synthesized heterocycles were confirmed by X-ray crystallography.  相似文献   

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以乙醇为溶剂,冰醋酸为催化剂,4-氨基-5-(1-苯基-3-甲基-5-氯吡唑)-1,2,4-三唑-3-硫酮(1)与芳醛经缩合反应合成了7个新型的4-取代苯次甲亚胺-5-(1-苯基-3-甲基-5-氯吡唑)-4H-1,2,4-三唑-3-硫酮(3a~3g),收率66%~74%,其结构经1H NMR,IR及元素分析表征。合成4-(苯次甲亚胺)-5-(1-苯基-3-甲基-5-氯吡唑)-2H-1,2,4-三唑-3-硫酮(3a)的最佳反应条件为:以乙醇为溶剂,乙酸为催化剂,1 10 mmol,n(苯甲醛)∶n(1)=1.2,于75℃反应3 h,产率74%。  相似文献   

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A stereoselective and economic synthesis of the carbapenem sidechain (2S, 4S)-4-ace-tylsulphanyl-2-[(S)1-phenylethyl-carbamoyl] pyrrolidine-1-carboxylic acid 4-nitrobenzylester was developed. Due to the effect of spatial hindrance, only the (2S,4S) diastereomer 3 wasobtained by coupling 1 and the inexpensive racemic 2 catalyzed by EEDQ.  相似文献   

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通过3-苄基-4-芳酰基-1,2,4-三唑-5-巯基负离子在2-甲磺酰基-5-苯基-1,3,4-噁二唑环2-位上的亲核取代反应,制得13个新的(3-苄基-4-芳酰基-1,2,4-三唑-5-基)(5-苯基-1,3,4-噁二唑-2-基)硫醚衍生物.经元素分析、IR、~1H NMR和MS裂解碎片分析确认结构.初步观察了它们在0.01%浓度时对大肠杆菌繁殖的抑制作用.  相似文献   

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2-Phenyl-1, 2, 3-triazole-4-formylhydrazine (2) was prepared by hydrazinolysis of the corresponding ester 1. Reaction of 2 with CS2/KOH gave the oxadiazole derivatives (3) which via, Mannich reaction with different dialkyl amines furnished 3-N, N-dialkyl derivatives (4a-c). Also, condensation of 2 with appropriate aromatic acid in POCl3 yielded oxadiazole derivatives (5a-c), or with aldehydes and ketones afforded hydrazones (6a-c). Cyclization of (6a-c) with acetic anhydride gave the desired dihydroxadiazole derivatives (7a-c). On the other hand, reaction of dithiocarbazate (8) with hydrazine hydrate gave the corresponding triazole derivative (9) which on treatment with carboxylic acids in refluxing POCl3 yielded s-triazole[3,4-b]-1, 3, 4-thiadiazole derivatives (10a-b). The structures of all the above compounds were confirmed by means of IR, 1H NMR, MS and elemental analysis.  相似文献   

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近20年来,真菌感染特别是深部真菌感染日益引起人们的广泛关注[1]。三唑类抗真菌药物对真菌的选择性较高,代谢稳定,体内动态、安全性都较好,已成为目前抗真菌药物研究开发的重点[2]。三唑类抗真菌药物是细胞色素P450 14α 去甲基酶的抑制剂,可影响该酶所催化的真菌麦角甾醇的生物合成,导致真菌细胞膜破损而死亡[3,4]。1998年,SynPhar实验室及Taiho制药公司[5]研制开发的化合物Syn 2869采用了取代哌嗪作为侧链。体外实验表明,该化合物抗菌谱广,对多种念珠菌、隐球菌及曲莓菌均有效,体内实验中,与目前临床上治疗真菌感染的主要用药伊曲…  相似文献   

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4-Amino- and 4-ureido-1,2,3-triazole-5-carboxylic acid oxides, as well as their hydrazides and methylamide, were prepred via pyrimidine ring opening in isomeric 2-phenyl[1,2,3]triazolo[4,5-d]pyrimidine-5,7-dione N-oxides.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 674–676.Original Russian Text Copyright © 2005 by Yavolovskii, Oliinichenko, Kirpichenko, Ivanov.  相似文献   

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Introduction 1,2,4-Triazole derivatives represent an interesting class of heterocyclic compounds[1] and have become the most rapidly expanding group of antifungal compoundswith the advantages of toxicity, high oral bioavailability, and broad spectrum of activity against several fungi, including most yeasts and folanentous fungi[2-4].  相似文献   

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杨炳辉  吴学军 《中国化学》2000,18(1):118-120
A series of 2'-purine and pyrimidine derivatives of 1' ,4'-anhy-dro-2'-deoxy-D-arabitol (1) and 1', 4'-anhydro-2'-deoxy-D-altritol (2) were synthesized regio- and stereo-selectively from D-sorbitol through some conversion in high yields.  相似文献   

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