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1.
Previ0uslyitwasf0undthatphosph0amin0acidscouldstimulatemanyinterestingbioorganicreacti0nsI-3.In0rderfurthert0confirmthesignificanceofph0sphorusinbiochemistry,tw0m0delcomp0unds,anal0gue0fphosphorylaminoacidsc0ntainingP-Cbondandphosphorylglucoaminoacids,weresynthesized.Theirreacti0nswithalcoholandamin0acidwerealsoinvestigatedbyNMRandMSmeth0ds.Theresultsindicatedthatthereactioncharacteristicsofphosphorylbio1ogicalsmallmoleculesweredependentonthe'configuration,functiongroupsandpositions.(O,O-b…  相似文献   

2.
Quantum-chemical calculations with the MOPAC and HYPERCHEM programs and MNDO, AM1, and PM3 methods were used to identify the reaction center in the molecules of protonated acetamide and its analogs (alkylamides) and to determine the effect of their nature on reactivity. The results of calculations are supported by IR and UV data. The change in the reactivity of alkylamides during their reaction with inorganic acids is explained by the effect of the nature of a basic or acid partner.  相似文献   

3.
A facile one-pot method for the synthesis of 1,2,3,4-tetrahydroquinoline-3-carboxylic acids and their heterocyclic analogs based on the tert-amino effect. A set of 1,2,3,4-tetrahydroquinoline-3-carboxylic acids was readily prepared starting from various ortho-dialkylaminoaldehydes and Meldrum's acid using Me3SiCl in dimethylformamide (DMF) solution.  相似文献   

4.
Addition of Schiff bases derived from amino acid esters to appropriate vinylphosphoryl compounds, followed by hydrolysis of the adducts formed gives a series of new α-alkylated phosphorus-containing α-aminocarboxylic acids, viz. phosphonic and phosphinic analogs of glutamic acid.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 7, 2005, pp. 1140–1147.Original Russian Text Copyright © 2005 by Saratovskikh, Ragulin.  相似文献   

5.
Homologs of the natural isoflavonoid pseudobaptigenin containing benzodioxane and benzodioxepane fragments were synthesized. Methanesulfonyl, carbamoyl, aminomethyl, and coumarin-containing isoflavone derivatives were prepared.  相似文献   

6.
A straightforward synthesis of phenylalanine analogs is described. Cerium ammonium nitrate (CAN) mediated addition of azide to cinnamic ester, followed by reaction with sodium acetate afforded the α‐azidocinnamate in moderate yield. Hydrogenation of α‐azidocinnamate, followed by BOC, CBZ or Fmoc protection gave phenylalanine analogs. A new approach for synthesizing racemic p‐boronophenylalanine analog was also explored.  相似文献   

7.
The reaction of cholesteryl triphenylphosphonioacetate chloride with heterocyclic aldehydes and hetaroyloxyarenecarbaldehydes in the presence of base gave the corresponding cholesteryl esters of substituted propenoic acids possessing liquid crystal properties.  相似文献   

8.
Derivatives of the natural isoflavone formononetin were synthesized. Acylation and alkylation of the phenolic hydroxyls and the chromone ring were investigated.  相似文献   

9.
The amination of 2-nitroquinizarine using hydroxylamine gives 2-amino-3-nitroquinizarine, which, upon reduction, gives previously unreported 2,3-diaminoquinizarine, a key intermediate in the synthesis of heterocyclic analogs of 5,12-naphthacenequinone, namely, 4,11-dihydroxyanthra[2,3-d]imidazole-5,10-dione (imidazoloquinizarine), 4,11-dihydroxyanthra[2,3-d][1,2,3]triazole-5,10-dione (triazoloquinizarine), and 5,12-dihydroxynaphtho[2,3-g]quinoxaline-6,11-dione (pyrazinoquinizarine). __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1081–1088, July, 2005.  相似文献   

10.
蔡祖恽 《有机化学》1984,4(5):325-334
本文综述了前列环素及其类似物的合成。类似物包括有7-羰基—、10,10-二氟—、5-氯—,4-羰基—、6,9-硫—、6,9-氮—,6 a-碳—前列环素以及苯前列环素等。前列环素及其类似物是一类具有抑制血小板聚集的生物活性化合物。  相似文献   

11.
Synthesis of (--)-galactosylhydroxylysine (GHL, I), and its analogs (+)-2 and (+)-3, which are essential for development of assays for osteoporosis, is described starting from (2S,5R)-(+)-hydroxylysine (4).  相似文献   

12.
Nebularine, 9-(β-D -ribofuranosyl)-9H-purin-2-amine, and inosine phosphoramidites 8 , 16 , and 17 , respectively, were synthesized and incorporated into the GNRA tetraloop at different positions (see Scheme, Table, and Fig. 4). The oligomers were investigated by means of UV and CD spectroscopy to address the question of how the individual base-modified N-nucleosides contribute to changes in H-bonding and base-stacking interactions within the loop. Several CD spectra are given and compared with each other (Figs. 5 and 6). The exchange of the loop sequence in position 4 and 7 results in a distinct change in base stacking. CD-Band shifting allows us to advance the hypothesis that a transition from a GNRA-type towards a UNCG-type base stacking is observed.  相似文献   

13.
1-Carbamoyl-1H-benzotriazole (benzotriazole-1-carboxamide, 2a), an effective carbamoyl chloride substitute, and a range of its analogs can be synthesized in good yields in two very simple steps from 1,2-diaminobenzene. The facile preparation of the intermediate o-aminophenylurea is key to this process. A preliminary study of the reactivity of 2a has shown that once in solution in tetrahydrofuran (THF), the 1-carbamoyl isomer equilibrates to give a mixture of both 1- and 2-isomers. If the solvent is ethanol or water, equilibration occurs rapidly compared to the ultimate formation of solvolysis products.  相似文献   

14.
Five analogs of dimethylallyl diphosphate (DMAPP) with additional or shifted Me groups were converted with isopentenyl diphosphate (IPP) and the fungal variediene synthase from Aspergillus brasiliensis (AbVS). These enzymatic reactions resulted in the formation of several new terpene analogs that were isolated and structurally characterised by NMR spectroscopy. Several DMAPP analogs showed a changed reactivity giving access to compounds with unusual skeletons. Their formation is mechanistically rationalised and the absolute configurations of all obtained compounds were determined through a stereoselective deuteration strategy, revealing absolute configurations that are analogous to that of the natural enzyme product variediene.  相似文献   

15.
内吗啡肽-1和内吗啡肽-2(Endomorphin-1,EM-1;Endomorphin-2,EM-2)是阿片肽类化合物中近期发现的两种,被认为是μ型阿片受体(μ-opiate receptor,MOR)的高亲和性、高选择性的内源性配基^[1]。这一发现是阿片肽研究领域的又一次重大突破,尤其是EM-1与阿片受体相结合的作用^[2]、镇痛效应和降血压活性引起了广泛关注。Fiori等^[3]进而指出了EM-1的生物活性构象,当其处于膜模拟环境中时,认为主链采取伸展构象,2-Pro等^[3]进而指出了EM-1的生物活性构象,当其处于膜模拟环境中时,认为主链采取伸展构,2-Pro采取顺式构型;1-Tyr的侧链与3-Trp的侧链距离较近,而结合EM-1构象研究成果,合理替换了EM-1的2-/3-位氨基酸(Amino acid,Aa),用液相多肽合成法得到了EM-1及其6个类似物,并利用离体生物检定法研究了它们的阿片受体结合作用,以期有助于内吗啡肽进一步的基础及应用研究。  相似文献   

16.
A series of aryltetralin lignans 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j , 7k , 7l were synthesized as cytotoxic isodeoxypodophyllotoxin analogs. The title compounds 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j , 7k , 7l were synthesized from the reaction of (+)‐(R )‐4‐[benzo(d )(1,3)dioxol‐5‐ylmethyl]‐dihydrofuran‐2‐(3H )‐one with different arylaldehydes to afford benzyl alcohol analogs and subsequent cyclization with trifluoroacetic acid in dichromethane. The preliminary screening of the compounds against viability of blood cancer human cell line K562 revealed that compounds 7d , 7e , and 7f had higher inhibitory activity at 10 µg/mL concentration compared with etoposide as reference drug.  相似文献   

17.
One-Pot Synthesis of Phenytoin Analogs   总被引:1,自引:0,他引:1  
A series of phenytoin analogs (5,5-diphenylimidazolidine-2,4-dione or 5,5-diphenyl-hydantoin) were synthesized in 65–75% yield from the corresponding substituted benzils. The same products were also obtained directly from -hydroxy ketones via one-pot procedure.  相似文献   

18.
19.
以2,4,6-三羟基苯甲醛为原料制得中间体2,4,6-三甲氧基苯甲醛(2a)和2,4,6-三三氘甲氧基苯甲醛(2b);以4-烷氧基-3-硝基苄硫基乙酸为原料,经氧化、缩合-脱羧、还原、取代和水解5步反应合成了氘代Rigosertib类似物,收率80%~86%,其结构经1H NMR和MS表征。  相似文献   

20.
Thalifoline (1) and its analogs were synthesized from methyl 3-hydroxy-4-methoxy benzoate by prenyl etherification, Claisen rearrangement, oxidation, imine formation, reductive amination and intramolecular amidation. The last three steps, imine formation, reductive amination, and intramolecular amidation, were completed in one pot at room temperature.  相似文献   

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