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1.
It was established that the reaction of hexabromo-2,2-dithienyl with magnesium in the presence of ethyl bromide gives an organodimagnesium derivative, which reacts with oxalic acid esters to give 3,3,4,4-tetrabromo-5,5-dithienyl-diglyoxalic acid esters. Reduction of the latter with ethylmagnesium bromide leads to 3,3,4,4-tetrabromo-5,5-dithienyl-2,2-diglycolic acid esters.See [1] for Communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 468–470, April, 1981.  相似文献   

2.
Conclusions A new coumarin has been isolated from the roots ofSeseli sessiliflorum for which the structure of 3-angeloyloxy-2,2-dimethyl-4-(trans-3-methylthioacryloyloxy)-3, 4-dihydropyrano-5,6:8,7-coumarin has been proposed. This is the first time that esters of 3-methylthioacrylic acid have been found in the coumarin series.All-Union Scientific-Research Institute of Medicinal Plants. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 517–521, September–October, 1970.  相似文献   

3.
Conclusions A new coumarin, which has been called smyrniodidin, has been isolated from the roots ofSmyrniopsis aucheri acetoxy-1-methylethyl)-4-angeloyloxy-4,5dihydrofuro-2, 3: 7, 6-coumarin. Boiss. The NMR spectrum and a study of the saponification products of smyrnioridin have shown that it is 5-(1-  相似文献   

4.
Summary 2-O-Ethyluracil and 2-O-ethylthymine were silylated with 1,1,1,3,3,3-hexamethyldisilazane and condensed in the presence ofTMS triflate with 2,3-dideoxy-3-fluoro-D-erythro-pentofuranoside, 3-azido-2,3-dideoxy-D-erythro-pentofuranoside, and 2,3-dideoxy-3-phthalimido--D-erythro-pentofuranose derivatives to give the corresponding 2-O-ethyl nucleosides. Deprotection with saturated methanolic ammonia afforded the 2,3-dideoxy-3-fluoro-2-O-ethyluridines, whereas 3-azido-2,3-dideoxy-3-O-ethyluridine was obtained by deprotection with tetrabutylammonium fluoride in tetrahydrofuran. 3-Amino-2,3-dideoxy-3-O-ethyluridine could be obtained only by treatment of the corresponding 3-azido nucleoside with triphenylphosphine in pyridine. 3-Deoxy-2-O-ethyl-3-fluorothymidine (6b) showed moderate activity against HIV-1.
Synthese von 2-O-Ethyl-Analogen von 3-Azido- und 3-Fluor-23-dideoxyuridinen und Bestimmung ihrer biologischen Aktivität gegenüber HIV
Zusammenfassung 2-O-Ethyluracil und 2-O-Ethylthymin wurden mit 1,1,1,3,3,3-Hexamethyldisilazan silyliert und in Gegenwart vonTMS-triflat mit 2,3-Dideoxy-3-fluoro-D-erythro-pentofuranosid, 3-Azido-2,3-dideoxy-D-erythro-pentofuranosid und 2,3-Dideoxy-3-phthalimido--D-erythro-pentofuranosederivaten zu den entsprechenden 2-O-Ethyl-Nucleosiden umgesetzt. Entfernung der Schutzgruppe mit gesättigter methanolischer Ammoniaklösung lieferte 2,3-Dideoxy-3-fluor-2-O-ethyluridin; 3-Azido-2,3-dideoxy-3-O-ethyl-uridin wurde durch Entschützung mit Tetrabutylammoniumfluorid in Tetrahydrofuran erhalten. 3-Amino-2,3-dideoxy-3-O-ethyl-uridin konnte nur durch Behandeln des entsprechenden 3-Azido-Nucleosids mit Triphenylphosphin in Pyridin hergestellt werden. 3-Deoxy-2-O-ethyl-3-fluor-thymidin (6b) zeigt geringe Aktivität gegenüber HIV-1.
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5.
Convenient methods for the synthesis of chiral 2,3-seco-2-deoxynucleosides were developed. An isopropylidene protective group was used to block the 3,5-hydroxy groups in 2,3-seco-uridine. Conversion of the hydroxymethyl group to a methyl group was accomplished by chlorination with a mixture of CCl4 and Ph3P with subsequent reduction with n-Bu3SnH. 2,3-seco-2-Deoxyuridine was obtained after deacetonation. The (S) enantiomer was similarly synthesized starting from 1-(-D-arabinofuranosyl)uracil. 3-O-tert-Butyldimethylsilyl-5-O-(p-monomethoxytrityl)-2,3-seco-2-deoxyuridine, which has optically active centers at C(1) and C(4), was also synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 822–826, June, 1988.The authors thank Professor M. Ya. Karpeiskii for his constant interest in this research.  相似文献   

6.
Zusammenfassung Cyclohexanon bzw. Cyclopentanon sowie ihre durch Aldolreaktion entstehenden Dimeren reagieren mit Harnstoff im sauren Medium zu 5,6,7,8-Tetrahydrospiro[cyclohexan-1,4(1H)-chinazolin]-3(2H)-onen (2) bzw. zum Dihydrospiro-(cyclopentan-1,4(1H)-5H-cyclopenta[d]pyrimidin)-2(3H)-on (10). Substituierte Harnsotoffe geben Gemische der isomeren 5,6,7,8-Tetrahydro- und 4a,5,6,7-Tetrahydroverbindungen (2, 3) bzw. 6,7-Dihydro-tH- und 5,6-Dihydro-4aH-verbindungen (10, 11). Charakteristisch für2 (3),10 (11) ist die Reaktivität der Kernstellen 8 bzw. 7 gegenüber elektrophilen Agentien (2f-v, 3f-j, 9 a-i, 10 d-f). Äthylmalonsäurebis-trichlorphenylester bzw. Formaldehyd und prim. Amine führen2 in ein partiell hydriertes 1H-Pyrido[3,2,1-ij]chinazolintrion (6) bzw. 1H-Pyrimido[5,6,1-ij]chinazolinon (7) über. Die 1-Alkylverbindungen (2) geben mit Formaldehyd und primären Aminen Hexahydro-8a-hydroxy-4a,8-propanospiro-(cyclohexan-1,4(1H)-pyrido[4,3-d]pyrimidin)-2(3H)-one (8).
Heterocycles, XXV: tetrahydrospiro [cyclohexane-1,4(1H)-quinazoline]-2(3H)-ones
Cyclohexanone and cyclopentanone, resp., as well as their dimers (formed by aldol reaction) react with urea in the presence of acids to 5,6,7,8-tetrahydrospiro[cyclohexane-1,4-(1H)-quinazoline]-3(2H)-ones (2) and to the dihydrospiro-(cyclopentane-1,4(2H)-5H-cyclopenta[d]pyrimidine)-2(3H)-one (10), resp. Substituted ureas give the isomeric 5,6,7,8-tetrahydro- and 4a,5,6,7-tetrahydro compounds (2, 3), and 6,7-dihydro-5H- and 5,6-dihydro-4aH-compounds (10, 11), resp. Characteristic for2 (3),10 (11) is the reactivity of the nuclear places 8 and 7 with electrophilic agents (2f-v, 3f-j, 9a-i, 10d-f). Ethylmalonic acid bistrichlorophenylester resp. formaldehyde and primary amines react with2 to the partially-hydrogenated 1H-pyrido[3,2,1-ij]-quinazolinetrione (6) and 1H-pyrimido[5,6,1-ij]-quinazolinone (7), resp. The 1-alkyl compounds (2) give with formaldehyde and primary amines hexahydro-8a-hydroxy-4a, 8-propanospiro(cyclohexane-1,4-(1H)-pyrido[4,3-d]pyrimidine)-2(3H)-ones (8).
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7.
    
The synthesis has been performed of dephosphocoenzyme A, 4,4-di-0-(2,3-9-isopropylideneadenosineuronyl)pantethine, and of 4,4-di(2,3-isopropylideneadenosineuronylamino)-4,4-dideoxypantethine from 2,3-0-isopropylidene adenosineuronic acid, using as condensing agents the tert-butyl dicarbonatepyridine and the N,N-dicyclohexylcarbodiimide-N-hydroxysuccinimide systems, respectively.Vitaminy Scientific-Production Amalgamation, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 587–590, July–August, 1987.  相似文献   

8.
Summary Complexes of general formula MLmCl2 · nH2O, where M=cobalt(II) or nickel(II); L=2-(4-methyl, 2-pyridyl)-benzimidazole (mpbi), 2-(4-methyl, 2-pyridyl)benzothiazole (mpbt), 2-(4-methyl, 2-pyridyl)benzoxazole (mpbo), 2-(4-methyl, 2-quinolyl)benzoxazole (mqbo), or 2-(4-methyl, 8-quinolyl)benzoxazole (mqbo); m=1,2; n=0–3, were prepared and characterized by t.g.a., conductance and magnetic measurements, i.r. and diffuse-reflectance electronic spectra.All the ligands behave as bidentate and coordinate through the pyridine- and isoxazole-nitrogen atoms.The nickel complexes have distorted octahedral or fivecoordinate structures. The cobalt complexes arepseudo-tet- rahedral except Co(mpbo)2Cl2·2H2O where the metal is six-coordinate.  相似文献   

9.
In the presence of stannic chloride, 2,3-dichlorotetrahydrofuran adds to isoprene with the formation of 3-chloro-2-(4-chloro-2-methylbut-2-enyl)tetrahydrofuran and to piperylene and bivinyl with the formation, predominantly, of 3-chloro-2-(4-chloropent-2-enyl)- and 3-chloro-2-(4-chlorobut-2-enyl)tetrahydrofuran, respectively, with their allyl isomers. The amount of the latter was estimated from the NMR spectra at 20–30%.For part VII, see [1].  相似文献   

10.
With excess acyl halide 1-methyl-3-acyl-2-(1-methyl-2-benzimidazolyl)-4-benzimidazoline is converted to an unstable 1-methyl-3-acyl-2-(1-methyl-3-acyl-4-benzimidazolin-2-yl)benzimidazolium chloride, which undergoes intramolecular redox cleavage with the formation of 1,1-dimethyl-2,2-dibenzimidazolyl and an aldehyde and dissociates at the C-C bond that connects the benzimidazolium and benzimidazoline fragments into a carbene yield and a 1-methyl-3-acylbenzimidazolium chloride.See [1] for communication 1.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 339–342, March, 1987.  相似文献   

11.
Alkylation of 3-thiocarbamoyl-3,4,5,6-tetrahydropyridine-2(1H)-one with methyl iodide has given 5-methylthio-2,6-diazabicyclo[2.2.2]oct-5-en-3-one and 3-methyl-thiocarbonyl-3,4-dihydropyridine-2(1H)-one. Alkylation of 3-thiocarbamoyl-3,4-dihydridine-2(1H)-one with iodoacetamide affords 3-(1-amino-1-carbamoyl-3,4-methyl-thiomethylene)-1,4-dihydropyridine-2-one, which in acidic media is converted into 3-(4-oxo-3,5-dihydro-1,3-thiazol-2-ylidene)-1,4-dihydropyridine-2-one.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 787–794, June, 1989.  相似文献   

12.
The treatment of 2,5,8-tri(2,4-dinitrophenyl)benzotristriazole, 2,7-di(2,4-dinitrophenyl)-4-nitrobenzo[1,2-d3,4-d]bistriazole, and 4,4-dicarboxy-5,5-bis[2- (2,4-dinitrophenyl)-2H-1,2,3-triazole with sodium methylate leads to loss of the 2,4-dinitrophenyl group as 2,4-dinitroanisole and formation of benzotristriazole, 4-nitrobenzo[1,2-d3,4-d]bistriazole, and 4,4-dicarboxy-5,5-bis-1H-1,2,3-triazole, respectively, in good yields.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1364–1367, October, 1993.  相似文献   

13.
New tricylic heterocyclic systems and their methyl derivatives are synthesized. They are 2-methylimidazo[5, 4-e]benzo-1, 2, 3-thiadiazole, 2-methylimidazo[5, 4-g]benzo-1, 2', 3-thiadiazole, 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole, and 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole. Quaternary salts of the 1, 2-dimethyl derivatives are used to prepare symmetrical and unsymmetrical trimethinecyanines and dimethinemerocyanines containing rhodanine groups. The absorption maxima of the dyes are displaced towards the long wavelength region compared with imidacarbocyanines. It is shown that when 1, 2-dimetnyl-5-aminobenzoimidazole is thiocyanated, the thiocyano group enters the benzoimidazole ring at position 4, and that 1, 2-dimethylimidazo[5, 4-e] benzo-1, 2, 3-thiadiazole is less basic than its isomer 1, 2-dimethylimidazo[5, 4-g]benzo-1, 2, 3-thiadiazole.  相似文献   

14.
The reactions of 4-bromo-1-(5-nitro-2-furyl)but-1-en-3-one and its 2-methyl and 2-chloro derivatives with thiourea and its N-allyl and N-phenyl derivatives have yielded 2-amino-4-[-5-nitro-2-furyl)-vinyl]thiazole and its - and N-substituted derivatives. 2-Amino-4-[-(5-nitro-2-furyl)vinyl]thiazole and its -methyl derivative have also been prepared by the direct reaction of the corresponding , -unsaturated ketones with bromine and an excess of thiourea in chloroform, as was shown by a comparison of UV spectra. A series of N-acyl derivatives of the aminothiazoles has been obtained. UV and IR spectra are given.  相似文献   

15.
Oxidation of 4-[-morpholino--(2-hydroxyphenyl)]methyl-2,6-di-(tert-butyl)-phenol (I) follows an unusual course, with formal loss of the benzyl carbon atom, to give 2,6-di(tert-butyl)-4-morpholino-4-(2-hydroxyphenyl)cyclohexa-2,5-dienone (II), which is thermochromic in solution. This property is due to the dissociation of (II) into morpholine and 3,5-di(tert-butyl)-2,4-diphenoxyquinone. The structure of (II) was established directly by x-ray diffraction, which enabled its conformational features to be related to its thermochromic properties. An x-ray examination of 3,3,5,5-tetra(tertbutyl)-2,4-diphenoquinone (X), together with the direct synthesis of the thermochromic analog of (II) (2,6-di(tert-butyl)-4-morpholino-4-[2-hydroxy-3,5-di(tert-butyl)phenyl]cyclohexa-2,5-dienone) (XI) from (X) and morpholine, confirmed the proposed mechanism of thermochromic dissociation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1121–1129, May, 1991.The authors thank V. I. Minkin and A. S. Morkovnik for participating in discussions of this work.  相似文献   

16.
A method was developed for the development of amino acids and some of their derivatives on Chromatographic paper by means of dibepin-8-[2,3(CO),6,5(CO)-dibenzoylene-4-pyridyl]-l-naphthoyl chloride. The sensitivity was 2 g in the case of glycine ethyl ester hydrochloride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 357–358, March, 1972.  相似文献   

17.
3-Aminoindoles substituted at C-2 and C-5 of the indole ring are converted by the action of Vilsmeier complexes into N-(indol-3-yl)-N,N-dialkylamidines. When C-2 is unsubstituted, the formylation proceeds but not the acetylation of this position. N-(Indol-3-yl)-N,N-dimethylacetamidine reacts with the complex obtained from DMF and POCl3 to give 2-dimethylamino-3-formyl--carboline. The optimal conditions were found for the conversion of amidines to amides.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 76–81, January, 1985.  相似文献   

18.
Using the method of initial rates, a study has been carried out on the different kinetic behavior of the acid and base forms of oxacillin. The acid catalytic constants of both species are determined. The acid form is much more stable with respect to hydrolysis.
, . . , .
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19.
By oxidation and the identification of the oxidation products, it has been shown that the -[4-(2-alkoxy-5-alkoxycarbonylmethylphenoxy)-3-methoxyphenyl] ethylamides of 4-benzyloxyphenylacetic acid obtained previously and differing in their physicochemical properties are based on the same skeleton and differ only in their spatial configuration, since on Bischler-Napieralski cyclization they give isomeric dihydroisoquinoline compounds. The structure of the latter was established by oxidation to the isomeric acids 2,2-dimethoxy-3,4,5-tricarboxy(diphenyl ether) and 2,2-dimethoxy-4,5,5-tricarboxy-(diphenyl ether); the latter is identical with the compound obtained by the degradation of the methyl ester of natural tubocurarine. 1-(4Benzyloxybenzyl)-6-methoxy-7-(2-methoxy-5-methoxycarbonyl methylphenoxy)-N-methyl-1,2,3,4-tetrahydroisoquinoline and a compound isomeric with it have also been synthesized, and the former has been shown to be identical with a substance obtained by independent synthesis from the 4-benzyl ether of N-methylcoclaurine. During the synthesis of the latter it was shown that cyclization takes place unambiguously without the formation of isomeric compounds.For part XIII, see [2].  相似文献   

20.
Zusammenfassung Cumarin reagiert leicht mit Malonsäuredinitril in 4-Stellung nach Art einerMichael-Addition. Die durch Ammoniak bewirkte Anlagerung führt zum 3,4-Dihydrocumarin-4-cyanessigsäure-amidin IV, in Gegenwart von NaOH entsteht durch Aufnahme von 2 Mol Malonitril 3,4-Dihydrocumarin-4-[1, 3, 3-tricyan-2-aminopropen-(2)] XI. Es werden Abbauversuche und Reaktionsverlauf näher beschrieben.  相似文献   

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