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A reaction of methyl (4R,5R)-4,5-epoxy-2(E)-hexenoate 1 with N-benzylmethylamine gave a diastereomerically pure methyl (4R,5R)-4,5-epoxy-(3S)-N-benzylmethylamino hexanoate 6 and methyl (4S,5R)-4-N-benzyl-methylamino-5-hydroxy-2(E)-hexenoate 7. The former was chemoenzymatically converted to (-)-osmundalactone 11, which is an aglycone of osmundalin. On the other hand, the directly conjugated addition of dimethylamine to methyl (4S,5S)-4,5-epoxy-2(E)-hexenoate 1 followed by treatment with MeOH at 40 degrees C exclusively provided methyl (4R,5S)-4-dimethylamino-5-hydroxy-2(E)-hexenoate 16, which was converted into L-(-)-forosamine 18. 相似文献
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S. G. Krivokolysko V. D. Dyachenko E. B. Rusanov V. P. Litvinov 《Chemistry of Heterocyclic Compounds》2001,37(8):987-992
4-(2-Chlorophenyl)-3-cyano-6-hydroxy-5-(2-thienoyl)-6-trifluoromethylpiperidin-2-thione, which was used for the synthesis of 2-allylthio-4-(2-chlorophenyl)-3-cyano-6-hydroxy-5-(2-thienoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine, was obtained by the reaction of 2-thienoyltrifluoroacetone with 2-chlorophenylphenylmethylenecyanothioacetamide or with a mixture of 2-chlorobenzaldehyde and cyanothioacetamide in the presence of N-methylmorpholine. The molecular and crystal structure of the piperidinthione have been established by X-ray crystallography. 相似文献
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M Miyauchi R Endo K Watanabe Y Kawahara M Iwata I Kawamoto 《Chemical & pharmaceutical bulletin》1990,38(6):1587-1590
Acyloxyalkyl esters (2a-d), alkyloxycarbonyloxyalkyl esters (2e-g) and (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl ester (2h) of (5R,6S)-2-(2-fluoroethylthio)-6-[(1R)-1-hydroxyethyl]penem-3- carboxylic acid (1) were synthesized. Enhanced oral absorption was observed in mice reflecting increased lipophilicity, compared with the parent 1 itself. Among them, the ester 2h showed a prolonged plasma level and a large area under the blood concentration-time curve (AUC) in rats. These ester-type prodrugs of penem 1 in phosphate buffer (pH 6.86) were much more stable than those of cephalosporins which easily degraded via isomerization to delta 2 cephalosporins. 相似文献
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《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2663-2666
Protonation of the highly reactive 1:1 intermediates, produced in the reaction between triphenylphosphine and dimethyl acetylenedicarboxylate, by 4-bromophenol leads to vinyltriphenylphosphonium salt, which undergoes aromatic electrophilic substitution reaction with conjugate base to produce dimethyl 2-(5-bromo-2-hydroxyphenyl)-3-(triphenylphosphoranylidene)butanedioate. Silica gel was found to catalyze conversion of dimethyl 2-(5-bromo-2-hydroxyphenyl)-3-(triphenylphosphoranylidene)butanedioate to methyl 6-bromo-2-oxo-2H-chromene-4-carboxylate in solvent-free conditions at 80°C in fairly high yield. 相似文献
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Dae-Kee Kim Young-Woo Kim Jongsik Gam Ganghyeok Kim Jinsoo Lim Namkyu Lee Hun-Taek Kim Key H. Kim 《Journal of heterocyclic chemistry》1996,33(4):1275-1283
A series of 1-(alkoxymethyl)-5-alkyl-6-(phenylselenenyl)uracils and -2-thiouracils modified at the 3- and/or 5-position of the C-6 phenylselenenyl ring with methyl or fluoro substituent has been synthesized and tested for their ability to inhibit HIV-1 replication. Lithiation of the acyclic uracil and 2-thiouracil derivatives 11-14 and 27-32 with lithium diisopropylamide or lithium bis(trimethylsilyl)amide followed by reaction with an appropriate diaryl diselenide afforded 6-arylselenenyl compounds 18-26 after removal of the tert-butyldimethylsilyl protecting group and 35-47 . Compounds 48-54 were prepared from compounds 38-44 by oxidative hydrolysis of the thione function. Of these compounds, 50 inhibited HIV -1 replication in human T4 lymphoblastoid cells at a 50% effective concentration (EC50) of 0.0047 μM with a selectivity index of >42600. 相似文献
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The Knoevenagel condensations of 5-[3-(trifluoromethyl)phenyl]furan-2-carbaldehyde with seven compounds containing an active
methyl or methylene group have been studied. The compounds used were: methyl 2-cyanoacetate, malononitrile, 2-furylacetonitrile,
acetophenone, 2-thioxo-1,3-thiazolidin-4-one (rhodanine), 5,5-dimethylcyclohexane-1,3-dione (dimedone), and methyl 2-azidoacetate.
The effect of microwave irradiation on the condensation reactions was studied and compared with “’classical”’ conditions.
Thermolysis of methyl 2-azido-3-{5-[3-(trifluoromethyl)phenyl]-2-furyl}propenoate afforded methyl 2-[3-(trifluoromethyl)phenyl)]-4H-furo[3,2-b]pyrrole-5-carboxylate.
(2E)-3-{ 5-[3-(Trifluoromethyl)phenyl]-2-furyl}propenoic acid was converted to the corresponding azide, which was cyclized
on heating into 2-[3-(trifluoromethyl)phenyl)]-4,5-dihydrofuro[3,2-c]pyridin-4-one. The latter after successive action of
POCl3 and NH2NH2-Pd/C gave 2-[3-(trifluoromethyl)-phenyl]furo[3,2-c]pyridine.
Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 825–831, June, 2006. 相似文献
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The optimum route for the synthesis of methyl esters of N-[(4-substituted amino)-5-cyano-2-methylthiopyrimidin-6-yl]amino acids (which are starting materials for preparing the methyl esters of the corresponding 5-amino-4-(substituted amino)pyrrolo[2,3-d]pyrimidine-6-carboxylic acids) is via subsequent reactions of 4,6-dichloro-2-methylthiopyrimidine-5-carbonitrile with amines and methyl glycinate. In some examples, the reaction of methyl N-(4-chloro-2-methylthio-6-pyrimidinyl)aminoacetate with amines occurs to give the corresponding acid amides. The previously unknown synthesized derivatives of pyrimidin-6-yl amino acids and 4,5-diaminopyrrolo[2,3-d]pyrimidine- 6-carboxylic acids possess fungicidal properties.Vilnius University, Vilnius 2006, Lithuania. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No 7, pp. 955–961, July, 2000. 相似文献
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吡喃酮是许多天然产物的结构单元,我们曾由4-异丁酰基庚二酸在过量醋酸酐及乙酰氯存在下回流得到7-氧代-8,8-二甲基-△~9-六氢香豆素.本文由二氰乙基-β-二酮进行酮解水解反应得到4-酰基庚二酸1_(a-c)。 在过量醋酸酐、乙酰氯存在下由1_a、1_c为底物进行反应没有得到双环的香豆素衍生物.其产物和单纯以乙酐为缩合剂时的产物2_a、2_c相同,产率分别为68%、63%。2_c可在硫酸铁催化 相似文献
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O. V. Koryakova M. L. Isenov E. S. Filatova O. V. Fedorova 《Journal of Structural Chemistry》2017,58(1):38-44
Vibrational spectra of 1,2-bis(2-aminophenoxy)-ethane, 1,5-bis(2-aminophenoxy)-3-oxapentane, and 1,8-bis(2-aminophenoxy)-3,6-dioxaoctane–podands, different in the length of oxyethylene fragments, are measured and their single crystal X-ray diffraction analysis is performed. It is demonstrated that the strength of intermolecular hydrogen bonds (IMHB) with the participation of NH groups increases with the elongation of the oxyethylene spacer. According to the XRD data for 1,2-bis(2-aminophenoxy)-ethane, the weakest hydrogen bonds are characteristic. From the IR spectra, important intermolecular hydrogen bonds are typical of 1,8-bis(2-aminophenoxy)-3,6-dioxaoctane having the longest oxyethylene fragment. 相似文献
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A convenient approach for the preparation of(1S,3’R.4’S,5’S,6’R)-5-chloro-6-[(4-ethylphenyl)methyl]- 3’,4’,5’,6’-tetrahydro-6’-(hydroxymethyl)-spiro[isobenzofuran-1(3H),2’-[2H]pyran]-3’,4’,5’-triol is developed. The targeted compound was synthesized from 2-bromo-4-methylbenzoic acid in nine steps and the isomers of undesired ortho-products were avoided during the preparation. 相似文献
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S. G. Krivokolysko V. D. Dyachenko A. N. Chernega V. P. Litvinov 《Chemistry of Heterocyclic Compounds》2001,37(10):1208-1215
The condensation of 2-chlorobenzaldehyde with cyanothioacetamide and 2-thenoyltrifluoroacetone in the presence of N-methylmorpholine takes place stereoselectively and leads to the formation of N-methylmorpholinium 4,5-trans-4-(2-chlorophenyl)-3-cyano-6-hydroxy-5-(2-thenoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine-2-thiolate. The latter was used to synthesize the corresponding 2-alkylthiotetrahydropyridines. The structure of 4,5-trans-4-(2-chlorophenyl)-3-cyano-6-hydroxy-2-methallylthio-5-(2-thenoyl)-6-trifluoromethyl-1,4,5,6-tetrahydropyridine was determined by X-ray crystallographic analysis. 相似文献
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The title compound 2-amino-4-chloro-5-(4-methylbenzyl)-6-methylpyrimidine (C26H28Cl2N6, Mr = 495.44) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 14.892(7), b = 6.129(3), c = 14.889(7) , β = 109.795(8)°, V = 1278.7(10) 3, Z = 2, F(000) = 520, Dc = 1.287 g/cm3, μ = 0.280 mm-1, the final R = 0.0577 and wR = 0.1589 for 1357 observed reflections with I > 2σ(I). A total of 6091 reflections were collected, of which 2257 were independent (Rint = 0.033). The X-ray analysis reveals that the chlorine atom and methyl of the title compound are disordered. 相似文献
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Nedolya N. A. Tarasova O. A. Albanov A. I. Trofimov B. A. 《Russian Journal of Organic Chemistry》2017,53(1):134-136
Russian Journal of Organic Chemistry - Aromatization of 5-methoxy-6-(methylsulfanyl)-2-[(vinyloxy)methyl]-2,3-dihydropyridine by the action of potassium tert-butoxide in DMSO afforded a mixture of... 相似文献
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Reactions of 3-methyl-6-[4-(4-hydroxyphenyl)-1-piperazinyl]-2(3H)-benzoxazolone, 3-methyl-6-[4-(4-hydroxy-phenyl)-1-piperazinyl]-2(3H)-benzothiazolone and 1,3-dimethyl-5-[4-(4-hydroxyphenyl)-1-piperazinyl]-2(3H)-benzimidazolone with cis-{[2-(2,4-dichlorophenyl) -2-(1H-imidazol-1-ylmethyl)]-1,3-dioxolan-4-yl}methyl meth-anesulfonate in the presence of sodium hydride furnish the title compounds. 相似文献
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Davies SG Díez D El Hammouni MM Garner AC Garrido NM Long MJ Morrison RM Smith AD Sweet MJ Withey JM 《Chemical communications (Cambridge, England)》2003,(19):2410-2411
Comparison of the kinetic and parallel kinetic resolutions of methyl (RS)-5-tert-butyl-cyclopentene-1-carboxylate allows for the efficient synthesis of both (1R,2S,5S)- and (1S,2R,5R)-enantiomers of methyl 2-amino-5-tert-butyl-cyclopentane-1-carboxylate. 相似文献
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1,6-Additions to 3-Methyl-5-methylidene-2(5H)-furanone Derivatives The anions of thiophenol, methyl malonate and malononitrile react with 3-methyl-5,6-dihydro-2 (4H)-benzofuranone ( 1c ) by the formation of the corresponding 1,6-addition products cis- 5c (63%), trans- 6 (42%) and trans- 7 (76%), respectively. Likewise, the reaction of 3-methyl-5-methylidene-2 (5H)-furanone ( 1b ) with thiophenol yields the 1,6-addition product 5b (66%), and with the sodium salt of methyl aceto-acetate the 1,6-addition product 8 (11%) and the dispiro-dilactone 9 (39%). 相似文献
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Shklyaev Yu. V. Nifontov Yu. V. Shashkov A. S. Firgang S. I. 《Russian Chemical Bulletin》2002,51(12):2234-2237
Reactions between p-methylanisole, isobutyraldehyde, and nitriles (acetonitrile, methyl thiocyanate, or ethyl cyanoacetate) in conc. H2SO4 yield 1-substituted (R,S)-8-(2-methoxy-5-methylphenyl)-3,3,9-trimethyl-2-azaspiro[4.5]deca-1,7-dien-6-ones. 相似文献
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A. P. Molchanov T. Q. Tran A. V. Stepakov G. L. Starova R. R. Kostikov 《Russian Journal of Organic Chemistry》2014,50(1):78-82
N-Aryl-C-(arylcarbamoyl)nitrones regioselectively add to methyl 2-(2-phenylcyclopropylidene)-acetate and methyl 2-methylidene-3-phenylcyclopropanecarboxylate to give in each case two diastereoisomeric 5-oxa-6-azaspiro[2.4]heptane-4-carboxylates. 相似文献