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以L-谷氨酸和苯甲醛为起始原料,经7步反应合成了重要中间体(2S,5R)-1-苄基-5-(2-羟乙基)吡咯烷-2-羧酸叔丁酯(1),总产率19%;1经TBDMSCl保护羟基后,用10%Pd/C催化氢解去除苄基制得游离胺(2S,5R)-5-(2-二甲基叔丁基硅氧烷基乙基)吡咯烷-2-羧酸叔丁酯(3);3与Boc-β-Cl-ala,在碱性条件下偶合得氯代烃消去产物(2S,5R)-1-[(2-叔丁氧甲酰胺基)丙烯酰基]-5-(2-二甲基叔丁基硅氧烷基乙基)吡咯烷-2-羧酸叔丁酯(4),或在中性条件下偶合得(2S,5R)-1-[(R)-2-叔丁氧甲酰胺基-3-氯丙酰基]-5-(2-二甲基叔丁基硅氧烷基乙基)吡咯烷-2-羧酸叔丁酯(5);4或5经四丁基氟化铵去除TBDMS保护并发生关环反应合成了新型的七元醚环化合物(4R,7S,9R)-4-甲基-4-叔丁氧甲酰胺基-5-羰基-3-氧杂氮杂卓[1,4]并吡咯[1,2-d]-7-羧基叔丁酯(简称6);6于室温在氯仿中静置2 d~3 d自发转换为其构象异构体(4S,7S,9R)-6(简称6’,6/6’=1/9),其结构经1H NMR,13C NMR,2D NMR和HR-ESI-MS表征。 相似文献
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以(S)-2-氨甲基-1-乙基吡咯烷为原料,合成了新型手性双功能有机催化剂(S)-1-[3,5-二(三氟甲基)苯基]-3-(1-乙基吡咯烷基-2-甲基)硫脲(2,产率82.2%).用2催化对甲氧基苯甲醛与硝基甲烷的不对称Henry反应,制得(R)-1-(4-甲氧基苯基)-2-硝基乙醇(3, 84%ee);3经Pd/C催化氢化得到(R)-2-氨基-1-(4-甲氧基苯基)乙醇(4);4与反式肉桂酰氯反应合成了(R)-aegeline,总产率37.6%(以对甲氧基苯甲醛计).化合物的结构经1H NMR, 13C NMR和MS表征. 相似文献
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以盐酸金刚烷胺和L-脯氨酸为原料,经羟基化、氯乙酰化及氨基化反应合成了维格列汀相关物质(S)-1-[2-(3-羟基-金刚烷-1-氨基)-乙酰基]吡咯烷-2-羧酸(3),其结构经1H NMR, 13C NMR和MS(ESI)确证。采用Box-Behnken响应面法优化3的合成工艺。结果表明最优反应条件为:1-(2-氯乙酰基)吡咯烷-2-甲酸与3-氨基-1-金刚烷醇的摩尔比为2:1、三乙胺0.006 mol,于65 ℃反应4 h, 3的平均收率为82.84%,纯度98.8%,可作为维格列汀相关物质检测的对照品。 相似文献
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以N-丙酰基-(3R,4S)-3-甲基-4-苯基-2-羰基噁唑啉与N-(叔丁氧羰基)-S-脯氨醛为原料,经羟醛缩合反应合成了高立体专一性、具有三个手性中心的(4S,5S,2'R,3'R,2"S)-3-[3'-(N-叔丁氧羰基-2"-吡咯烷基)-3'-羟基-2'-甲基丙基)]-4-甲基-5-苯基-2-羰基噁唑烷酮(6);6脱去手性辅基,甲基化3'-羟基合成了抗肿瘤活性肽海兔毒索10的关键合成子--(2S,3S,2's)-3-(N-叔丁氧羰基-2'-吡咯烷基)-3-甲氧基-2-甲酸丙酸,其结构经1H NMR,13C NMR,m和MS表征. 相似文献
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氰基亚甲基三苯基胂(1)与2-全氟炔酸甲酯(2)反应,生成加合产物2-三苯胂基-3-全氟烷基-4-氰基丁烯-3-酸甲酯(3)通过3的水解,立体选择性地合成了3-全氟烷基-4-氰基-3-丁烯酸甲酸甲酯[5(Z),6(E)],Z:E约为95:5.氰基亚甲基三苯基膦(7)与2亦可反应,生成加合产物2-三苯基膦叉-3-全氟烷基-4-氰基丁烯-3-酸甲酯的顺式和反式异构体(8)和(9).总产率在90%左右.8与9的比例受反应介质极性的影响,若溶剂极性增大,则有利于8的生成. 相似文献
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Philip L. Southwick R. Madhav James A. Fitzgerald 《Journal of heterocyclic chemistry》1969,6(4):507-516
Methods are described for the synthesis of 6,7-dihydro-5H-pyrrolo[3,4-d]pyrimidines having an aryl substituent in the 6-position. 4-Hydroxy-, 4-amino, 2-amino-4-hydroxy and 2,4-diamino derivatives were obtained. The synthetic route involved the preparation of 1-aryl-4-cyano- or 4-carboalkoxy-3-pyrrolidinones and 1-aryl-4-cyano- or 4-carboalkoxy-3-amino-3-pyrrolines as key intermediates. 相似文献
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Boris A. Trofimov Anastasiya G. Mal'kina Olesya A. Shemyakina Lyudmila I. Larina Grigorii G. Alexandrov 《Tetrahedron》2010,66(9):1699-3203
Adenine (9H-purin-6-amine) adds readily to available α,β-acetylenic γ-hydroxy nitriles under mild conditions (molar ratio 1:1, K2CO3, DMF, rt, 10 min) to afford chemo-, regio- and stereospecifically (Z)-3-(6-amino-9H-purin-9-yl)-4-hydroxy-4-alkyl-2-alkenenitriles, novel functionalized acyclic nucleoside analogues (95-98% yield). Under similar conditions (K2CO3, DMF, rt, 1 h), 8-azaadenine (3H-[1,2,3]triazolo[4,5-d]pyrimidin-7-amine) reacts with 4-hydroxy-4-methyl-2-pentynenitrile nonselectively at the 7-, 8- and 9-positions to give the corresponding adducts in a 1:10.5:9 ratio, the total yield being 81%. Chemo-, regio- and stereospecific addition of 8-azaadenine to the above α,β-acetylenic γ-hydroxy nitriles leading to (Z)-3-(7-amino-2H-[1,2,3]triazolo[4,5-d]pyrimidin-2-yl)-4-hydroxy-4-alkyl-2-alkenenitriles in 44-90% yield is attained when the reaction is carried out without solvent in the presence of Et3N (30 mol %), the molar ratio of 8-azaadenine:α,β-acetylenic nitriles being 1:2.0 (rt, 12-38 h). 相似文献
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T. A. Kuz'menko V. V. Kuz'menko A. F. Pozharskii O. V. Kryshtalyuk G. G. Aleksandrov 《Chemistry of Heterocyclic Compounds》1992,28(2):167-176
For the first time, 1-amino-3-alkylbenzimidazolinethiones were obtained by heating 1-amino-3-alkylbenzimidazolium iodides with sulfur in the presence of triethylamine. They were converted to 1-amino-3-alkyl-2-(methylthio)benzimidazolium salts, which, during reaction with CH-acid onions, gave the corresponding 1-amino-3-alkyl-2-methylenebenzimidazoline derivatives. Under conditions of alkaline or acid catalysis, the latter derivatives cyclized to 2-amino- or 2-hydroxy derivatives of pyrazolo[1,5-a]benzimidazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 205–214, February, 1992. 相似文献
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[reaction: see text] trans-(3S)-Amino piperidines bearing various alkyl and aryl substituents at the C-4 position were synthesized via a ring-closing metathesis reaction. The absolute stereochemistry was controlled using a protected D-serine as a starting material. Stereoselective hydrogenation of allylamines provided trans-(3S)-amino-(4R)-alkyl- and -(4S)-aryl-piperidines. This procedure presents the first method for the asymmetric synthesis of 4-substituted 3-amino piperidines. 相似文献
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Wayne Zeller 《Tetrahedron letters》2010,51(10):1380-1382
Regiospecific construction of 3-alkyl-4-hydroxybenzimidazoles is detailed. The synthetic route involves a novel O- to N-acyl transfer reaction to address the observed exclusive O-acylation of 2-amino-3-nitrophenol starting material. This efficient route provides the targeted 3-alkyl-4-hydroxybenzimidazoles in good yields, in five steps, without the use of chromatographic purification. These key intermediates were subsequently elaborated, as shown, to provide acylsulfonamide-derived potent EP3 receptor antagonists. 相似文献
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Twenty-six 5-azacytidine analogues have been synthesized, including 4-amino- 6-alkyl-1-pyranosyl/ribofuranosyl-1,3,5-triazin-2(1H)-ones 1a-j, 6-amino-4-alkyl/aryl-1- pyranosyl/ribofuranosyl-1,3,5-triazin-2(1H)-ones 2a-f and 4-amino-6-alkyl-1,3,5-triazin-2- yl-1-thio-pyranosides/ribofuranosides 3a-j. The antiproliferative activities of these synthetic analogues were investigated in human leukemia HL-60 cells. Ribofuranosyl S-nucleoside 3a, a bioisostere of 5-azacytidine, had a similar antiproliferative ability as that of the latter. Introduction of a methyl at the 6 position of 5-azacytidine and/or replacement of the ribofuranosyl moiety with pyranosyl sugars or disaccharides significantly decreased the antiproliferative activities of the 5-azacytidine derivatives. Several compounds with the replacement of pyranosyl sugars enhanced all-trans retinoic acid-induced differentiation ability in human leukemia HL-60 cells. 相似文献
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Taisei Ueda Satoko Asai Khoji Oiji Shin-Ichi Nagai Akito Nagatsu Jinsaku Sakakibara 《Journal of heterocyclic chemistry》1997,34(3):761-764
Treatment of 5-acylamino-6-hydroxy (or benzoyloxy)methyl-3-phenylpyrimidin-4(3H)-one 5,10 with 5% aqueous sodium hydroxide in ethanol gave 2-alkyl-5-hydroxymethyl-4-phenylcarbamoyl-1H-imidazoles 7,11 . Oxidation of 5-amino-6-benzoyloxymethyl-3-phenylpyrimidin-4(3H)-one 9 in the presence of copper( II ) chloride in alcohol gave 2-alkoxy-5-alkoxymethyl-4-phenylcarbamoyl-1H-imidazoles 12a,b accompanied by 5-amino-6-alkoxymethyl-3-phenylpyrimidin-4(3H)-ones 13a,b. 相似文献
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Homochiral α-dibenzylamino aldehydes, prepared from the corresponding α-amino acids, react with propargyl bromide and zinc in DMF/THF (1:1) or DMF/Et2O (1:1) at 20 °C to afford, in good yields and dr, homopropargylic 1,2-amino alcohols. anti Diastereomers were always formed as major products in this reaction. These compounds are versatile intermediates for a variety of synthetic targets: γ-amino-β-hydroxy-ketones, 4-amino-1,3-diols, 1,7-diamino-2,6-diols, and ω-amino-δ-hydroxy esters. 相似文献
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Ketenes readily cycloadded to (R)-tert-butyldihydrooxazole 2a-d to yield enantiomerically pure bicyclic cyclobutanones. The cycloadditions proceeded with unusual regiochemistry giving predominantly or exclusively protected α-amino-β-hydroxycyclobutanone derivatives. The adducts could be converted into a variety of interesting enantiopure intermediates equipped with many functional groups: α-amino-β-hydroxy cyclopropane carboxylic acid derivatives, α-amino-β-hydroxy succinic acid derivatives, α-amino-β-hydroxy lactones and lactams derivatives. 相似文献
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John B. Hynes Johnny P. Campbell John D. Hynes 《Journal of heterocyclic chemistry》1995,32(4):1185-1187
The reactions of ten ortho-fluoroketones with guanidine carbonate in N,N-dimethylacetamide were investigated as a new synthetic approach to 2-amino-4-alkyl- and 2-amino-4-arylquinazolines. The yields obtained ranged from low to moderate and were highly dependent upon the nature of the substituents on the reactant. Eight new quinazolines were elaborated in this study. 相似文献