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1.
Several disubstituted pyrazolo[3,4-d]pyrimidine, pyrazolo[1,5-a]pyrimidine and thiazolo[4,5-d]pyrimidine ribonucleosides have been prepared as congeners of uridine and cytidine. Glycosylation of the trimethylsilyl (TMS) derivative of pyrazolo[3,4-d]pyrimidine-4,6(1H,5H,7H)-dione ( 4 ) with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose ( 5 ) in the presence of TMS triflate afforded 7-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)pyrazolo-[3,4-d]pyrimidine-4,6(1H,5H)-dione ( 6 ). Debenzoylation of 6 gave the uridine analog 7-β-D-ribofuranosylpyrazolo[3,4-d]pyrimidine-4,6(1H,5H)-dione ( 3 ), identical with 7-ribofuranosyloxoallopurinol reported earlier. Thiation of 6 gave 7 , which on debenzoylation afforded 7-β-D-ribofuranosyl-6-oxopyrazolo[3,4-d]pyrimidine-4(1H,5H)-thione ( 8 ). Ammonolysis of 7 at elevated temperature gave a low yield of the cytidine analog 4-amino-7-β-D-ribofuranosylpyrazolo[3,4-d]pyrimidin-6(1H)-one ( 11 ). Chlorination of 6 , followed by ammonolysis, furnished an alternate route to 11 . A similar glycosylation of TMS-4 with 2,3,5-tri-O-benzyl-α-D-arabinofuranosyl chloride ( 12 ) gave mainly the N7-glycosylated product 13 , which on debenzylation provided 7-β-D-arabinofuranosylpyrazolo[3,4-d]pyrimidine-4,6(1H,5H)-dione ( 14 ). 4-Amino-7-β-D-arabinofuranosyl-pyrazolo[3,4-d]pyrimidin-6(1H)-one ( 19 ) was prepared from 13 via the C4-pyridinium chloride intermediate 17 . Condensation of the TMS derivatives of 7-hydroxy- ( 20 ) or 7-aminopyrazolo[1,5-a]pyrimidin-5(4H)-one ( 23 ) with 5 in the presence of TMS triflate gave the corresponding blocked nucleosides 21 and 24 , respectively, which on deprotection afforded 7-hydroxy- 22 and 7-amino-4-β-D-ribofuranosylpyrazolo[1,5-a]pyrimidin-5-one ( 25 ), respectively. Similarly, starting either from 2-chloro ( 26 ) or 2-aminothiazolo[4,5-d]pyrimidine-5,7-(4H,6H)-dione ( 29 ), 2-amino-4-β-D-ribofuranosylthiazolo[4,5-d]pyrimidine-5,7(6H)-dione ( 28 ) has been prepared. The structure of 25 was confirmed by single crystal X-ray diffraction studies.  相似文献   

2.
Zusammenfassung Hexahydro-8a-methylpyrimido[4,5-d]pyrimidin-2,7 (1H, 3H)-dione reagieren mit o-reaktiven Phenolen zu Hexahydro-10a-methyl-2H[1]benzopyrano[2,3-d]pyrimidin-2-onen.
Heterocycles, XVII: Hexahydro-8a-methylpyrimido[4,5-d]-pyrimidine-2,7 (1H, 3H)-diones
Hexahydro-10a-methyl-2H[1]benzopyrano[2,3-d]pyrimidin-2-ones have been synthesized by the reaction of hexahydro-8a-methylpyrimido[4.5-d]pyrimidine-2.7(1H, 3H)-diones with phenols having reactive o-positions.
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3.
4-Amino-1, 2, 5-selenadiazole-3-carboxylic acid and 4-amino-1, 2, 5-selenadiazole-3-carboxamides have been prepared by ring-cleavage of [1, 2, 5]selenadiazolo[3, 4-d]pyrimidin-7(6H)-one by basic reagents. The primary amide (III), as well as an N-alkyl amide, may be produced by the action of a primary amine. Hydrazine reductively cleaves the selenadiazole ring. The preparation of similar 4-ureido derivatives by ring-cleavage of [1,2,5]selenadiazolo[3, 4-d]pyrimidine-5, 7(4 H, 6H)-dione has been demonstrated with two examples. N-Butyl-4-ureido-1, 2, 5-selenadiazole-3-carboxamide is easily hydrolyzed in aqueous base to the corresponding acid, and it has been shown that this reaction proceeds by way of [1, 2, 5]selenadiazolo[3,4-d]pyrimidine-5, 7 (4H, 6H)-dione. The 4-amino-1, 2, 5-selenadiazole-3-carboxylic acid derivatives have marked cytotoxic, antibacterial, and antifungal activity.  相似文献   

4.
Synthesis and properties of hitherto unknown thiazolo[5,4-d]pyrimidine 1-oxides are described. For example, the reaction of 6-chloro-1,3-dimethyl-5-nitrouracil (I) with methyl thioglycolate in the presence of excess triethylamine afforded 2-methoxycarbonyl-4,6-dimethylthiazolo[5,4-d]pyrimidine-5,7-(4H,6H)dione 1-oxide (IIIa), which is a versatile intermediate for the preparation of various thiazolo[5,4-d]pyrimidine derivatives.  相似文献   

5.
Several 6-substituted thieno[2,3-d]pyrimidine-2,4(1H,3H)-dione derivatives were synthesized. 6-Ethoxycarbonyl derivatives 3 and 7 were prepared by treatment of 6-chloro-5-formyluracil 1 and 6-chloro-5-cyanouracil 6 with ethyl 2-mercaptoacetate in the presence of a base. Electrophilic substitution reactions (Vilsmeier-Haack reaction, bromination, and nitration) of 5,6-unsubstituted thieno[2,3-d]pyrimidine 9 , prepared by condensation of 6-mercaptouracil 8 with chloroacetaldehyde, afforded the corresponding 6-formyl-, 6-bromo-, and 6-nitrothieno[2,3-d]pyrimidines 10, 15 and 16 , respectively.  相似文献   

6.
Diastereoselective [3+2] cycloaddition of azomethine ylide to 1,3-dimethyl-6-(2-oxo-1,2-dihydro-3H-indol-3-ylidene)-3a,9a-diphenyl-3,3a,9,9a-tetrahydroimidazo[4,5-e]thiazolo[3,2-b]-[1,2,4]triazine-2,7(1H,6H)-dione yields hitherto unknown 1,1′,3-trimethyl-3a,9a-diphenyl-3,3a,9,9a-tetrahydrodispiro(imidazo[4,5-e]thiazolo[3,2-b][1,2,4]triazine-6,3′-pyrrolidine-4′,3″-indole)-2,2″,7(1H,1″H)-triones.  相似文献   

7.
Treatment of 5-cyano-1,3-dimethyluracil ( 8 ) with an activated acetonitrile, such as malononitrile, ethyl cyanoacetate or cyanoacetamide, in base afforded 7-amino-6-cyano-, 7-amino-6-ethoxycarbonyl-, and 7-amino-6-aminocarbonyl-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione ( 18b, 18c and 18d , respectively) in high yields. On the other hand, reaction of 8 with acetonitrile in base gave the Michael adduct, 5-cyano-6-cyanomethyl-5,6-dihydrouracil ( 15 , R = H), and the hydrated product, 1,3-dimethyluracil-5-carboxamide ( 9 ) as the major products, and 7-amino-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione ( 18a ) in only very low yield. Similar reaction with butanone gave 7-ethyl-1,3-dimethyl- and 1,3,6,7-tetramethylpyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione ( 10b and 10c ) in low yields. When 8 was treated with diethylmalonate in base, only a small amount of 6-ethoxycarbonyl-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4,7(1H,3H,8H)-trione ( 19 ) was obtained together with 1,3-dimethylpyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione ( 20 ) and 18c (also in low yields). Treatment of 8 in ethanolic sodium ethoxide without added carbon nucleophile gave significant amounts (14%) of 20 and a small amount of 18c .  相似文献   

8.
The synthesis of the congeners of uridine and cytidine in the pyrazolo[4,3-d]pyrimidine and pyrrolo[3,2-d]-pyrimidine ring system is described. Glycosylation of the trimethylsilyl (TMS) derivative of pyrazolo[4,3-d)pyrimidine-5,7(1H,4H,6H)-dione (4) with either 1-bromo- or 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose 5 and 6 , respectively in the presence of a Lewis acid catalyst gave the protected nucleoside 7 , which on debenzoylation afforded the uridine analogue 4-β-D-ribofuranosylpyrazolo[4,3-d]pyrimidine-5,7(1H,6H)-dione (8). Thiation of 7 gave 13 , which on deprotection yielded 4-β-D-ribofuranosyl-5-oxopyrazolo[4,3-d]pyrimidine-7(1H,-6H)-thione (14). Ammonolysis of 13 gave a low yield of the cytidine analogue 15. A chlorination of 7 , followed by amination furnished an alternative route to 15. A similar glycosylation of TMS-4 with 2,3,5-tri-O-benzyl-α-D-arabinofuranosyl chloride (16) gave mainly the N4 glycosylated product 17 , which on debenzylation furnished 4-β-D-arabinofuranosylpyrazolo[4,3-d]pyrimidine-5,7(1H,6H)-dione (18). 7-Amino-4-β-D-arabinofuranosylpyrazolo[4,3-d]pyrimidin-5(1H)-one (23) was prepared from 17 via the pyridinium chloride intermediate 21. Condensation of the TMS derivative of pyrrolo[3,2-d]pyrimidine-2,4(1H,3H,5H)-dione (24) with 6 , followed by deprotection of the reaction product gave 1-β-D-ribofuranosylpyrrolo[3,2-d]pyrimidine-2,4(3H,5H)-dione (26). Similarly, TMS-24 was reacted with 16 to give a mixture of the blocked nucleosides 31 and 32 , which on debenzylation afforded a mixture of two isomeric compounds 34 and 35. 1-β-D-Arabinofuranosylpyrrolo[3,2-d]pyrimidine-2,4(3H,5H)-dione (34) was converted to the ara-C analogue 38 via the 3-nitrotriazolyl intermediate 36. The structure of 38 was confirmed by single crystal X-ray diffraction studies.  相似文献   

9.
2H-5-Amino-6-cyano-3,7-dioxothiazolo[2,3-b]pyrimidine was subjected to ring formation affording thiazolo[2,3-b]pyrimidine derivatives. 2H-5-Amino-6-cyano-3,7-dioxo-2-phenylmethylenethiazolo[2,3-b]pyrimidine was also subjected to ring formation affording pyrimido[4,5-d]-, pyrano[2,3-d]-, and pyrido[2,3-d]thiazolo[2,3-b]pyrimidine derivatives. 2-Anilinothiocarbonyl-3,9-dioxo-8-imino-7-phenyl-6-thioxothiazolo[2,3-b]pyrimido[4,5-d]pyrimidine and 8-amino-3,9-dioxo-6-thioxothiazolo[2,3-b]pyrimido[4,5-d]pyrimidine reacted with α-haloactive-methylene compounds to afford heterocyclic compounds containing two, fused and isolated, thiazole moieties, respectively.  相似文献   

10.
An efficient and facile method for the synthesis of 5-arylindeno[2′,1′:5,6]pyrido[2,3-d] pyrimidine-2,4(3H)-dione and 7-arylbenzo[h]pyrimido[4,5-b]quinoline-8,10(5H,9H)-dione derivatives from the reactions of 2-arylidene-2,3-dihydroinden-1-one (or 2-arylidene-3,4- dihydronaphthalen-1(2H)-one) and 6-amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione under mild conditions was described. This is a simple, efficient, and very rapid synthetic method, which is believed to provide a useful process for the synthesis of these fused heterocyclic compounds. The products were confirmed by infrared, 1H NMR, 13C NMR, and high-resolution mass spectrometry.  相似文献   

11.
Several nucleoside derivatives of pyrimido[4,5-d]pyrimidine-2,4(1H,3H)-dione 1 and 2,4{1H,3H-pteridinedione 2 were prepared. Treating the appropriate silylated nucleobase with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofura-nose 3 in the presence of trimethylsilyl Inflate gave 4 and 8 which, upon debenzoylation, gave 5 and 9 , respectively. Treatment of 4 with phosphorus pentasulfide afforded the sulfur substituted compound 6 . Again, deprotection gave 7 . The arabinose derivatives were obtained by treating 1-O-acetyl-2,3,5-tri-O-benzoyl-D-arabinofuranose 10 with the silylated nucleobases to give 11 and 13 . Debenzoylation gave the free arabinonucleosides 12 and 14 respectively. The deoxy derivative 16 was prepared by the reaction of 1 with 1-chloro-3,5-di-O-acetyl-2-deoxy-D-ribofuranose 15 . Deacetylation of 16 with methanolic ammonia gave the α-anomer 17 .  相似文献   

12.
A new and efficient method for the synthesis of hitherto unreported spiro[benzo[4,5]thiazolo[3,2-a]chromeno[2,3-d]pyrimidine-14,3′-indoline]-1,2′,13(2H)-triones was developed via the Domino Knoevenagel condensation–Michael addition–intermolecular cyclization sequences of isatin derivatives, cyclohexane-1,3-diones, and 2-hydroxy-4H-benzo[4,5]thiazolo[3,2-a]pyrimidin-4-ones, employing 12-tungstophosphoric acid (H3PW12O40) as an effective and inexpensive catalyst.  相似文献   

13.
Reaction of 1,2,3,4-tetrahydro-2,4-dioxopyrido[2,3-d]pyrimidine with 3-bromoprop-1-yne gave 1-prop-2′-ynylpyrido[2,3-d]pyrimidine-2,4-dione ( 4a ), 3-prop-2′-ynylpyrido[2,3-d]pyrimidine-2,4-dione ( 4b ), and 1,3-diprop-2′-ynylpyrido[2,3-d]pyrimidine-2,4-dione ( 4c ). Subsequent boiling of 1,3-diprop-2′-ynylpyrido-[2,3-d]pyrimidine-2,4-dione ( 4c ) in formic acid afforded 1-methylimidazo[1,2-a]pyridyl-N-prop-2′-ynylamide ( 5 ) and 1-acetonyl-3-prop-2′-ynylpyrido[2,3-d]pyrimidine-2,4-dione ( 6 ).  相似文献   

14.
Zusammenfassung 5,6-Dihydro-2H-pyran-3-aldehyde reagieren mit Harnstoff zu 4-ureidooctahydropyrano[4,3-d]pyrimidin-2-ones. Einwirkung von Säure führt das 4-Ureidooctahydropyrano[4,3-d]pyrimidin-2-on in das 4-(2-Hydroxyäthyl)-hexahydropyrimido[4,5-d]pyrimidin-2,7-dion über.
Heterocycles, XVIII: 4-Ureido-octahydropyrano[4,3-d]-pyrimidinones
5,6-Dihydro-2H-pyran-3-aldehydes react with urea to give 4-ureidooctahydropyrano[4,3-d]pyrimidin-2-ones. 4-Ureidooctahydropyrano[4,3-d]pyrimidin-2-one is cleaved by HCl to 4-(2-hydroxyethyl)-hexahydropyrimido[4,5-d]pyrimidin-2,7-dione.
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15.
Synthesis of the pyrazolo[3,4-d]pyrimidin-3-one congeners of guanosine, adenosine and inosine is described. Glycosylation of 3-methoxy-6-methylthio-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-one ( 13 ) with 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose ( 16 ) in the presence of boron trifluoride etherate gave 3-methoxy-6-methylthio-1-(2,3,5-tri-O-benzoyl-β-D-ribofuranosyl)pyrazolo[3,4-d]pyrimidin-4(5H)-one ( 17 ) which, after successive treatments with 3-chloroperoxybenzoic acid and methanolic ammonia, afforded 6-amino-3-methoxy-1-β-D-ribofuranosylpyrazolo[3,4-d]pyrimidin-4(5H)one ( 18 ). The guanosine analog, 6-amino-1-β-D-ribofuranosylpyrazolo[3,4-d]pyrimidine-3,4(2H,5H)-dione ( 21 ), was made by sodium iodide-chlorotrimethylsilane treatment of 6-amino-3-methoxy-1-(2,3,5-tri-O-acetyl-β-D-ribofuranosyl)pyrazolo[3,4-d]pyrimidin-4(5H)one ( 19 ), followed by sugar deprotection. Treatment of the adenine analog, 4-amino-1H-pyrazolo[3,4-d]pyrimidin-3(2H)-one ( 11 ), according to the high temperature glycosylation procedure yielded a mixture of N-1 and N-2 ribosyl-attached isomers. Deprotection of the individual isomers afforded 4-amino-3-hydroxy-1-βribofuranosylpyrazolo-[3,4-d]pyrimidine ( 26 ) and 4-amino-2-β-D-ribofuranosylpyrazolo[3,4-d]pyrimidin-3(7H)-one ( 27 ). The structures of 26 and 27 were established by single crystal X-ray diffraction analysis. The inosine analog, 1-β-D-ribofuranosylpyrazolo[3,4-d]pyrimidine-3,4(2H,5H)-dione ( 28 ), was synthesized enzymatically by direct ribosylation of 1H-pyrazolo[3,4-d]pyrimidine-3,4(2H,5H)-dione ( 8 ) with ribose-1-phosphate in the presence of purine nucleoside phosphorylase, and also by deamination of 26 with adenosine deaminase.  相似文献   

16.
By the reaction of weak bases with N(2)-disubstituted 2-amino-4-thiazoliniminium chlorides 3, easily available by the reaction of thioureas 1 with α-chloroacetonitrile 2, N(2),N(2′)-persubstituted 2,4-diamino-5-(2-amino-4-thiazolyl)thiazoles 8 are formed. These new bis-thiazoles react, as exemplified with the dimorpholino derivative 8a, with different electrophilic reagent, such as phenyl isothiocyanate 9, 4-nitro-phenyldiazonium salt 11, or 4-dialkylaminobenzaldehydes 13 at their 5H-substituted thiazole moieties to give the corresponding thioanilides 10, azo compounds 12, and methine dyes 14, respectively. With sodium nitrite and the Vilsmeier reagent the thiazole 8a is transformed, via unstable intermediates, into the tricyclic 2,7-dimorpholinothiazolo[4,5-c]thiazolo[4,5-e]pyridazine 16 and 2,7-dimorpholinothiazolo[4,5-b]thiazolo[4,5-d]pyridine 19, respectively.  相似文献   

17.
Synthesis of 1,3-dipropyl-1H,3H-pyrazino, pyrido, pyrimido and pyrrolo[2,1-f]purine-2,4-diones, starting from 5,6-diamino-1,3-dipropylpyrimidine-2,4-dione 1 and 6-chloro-1,3-dipropylpyrimidine-2,4-dione 14 is described. A new synthetic approach to 1,3-dipropyl-1H,3H-pyrido(or pyrazino)[1′,2′-1,2]pyrimido[4,5-d]pyrimidine-2,4,5-triones 19 e, f, h has been also developed.  相似文献   

18.
A reaction of 5-cyano-1,3-dimethyluracil (1, R = CN) with acetone in base afforded 1,3,7-trimethylpyrido-[2,3-d]pyrimidine-2,4(1H,3H)dione ( 9a ) in a moderate yield. From a reaction mixture of 1 (R = CN) with butanone, 1,3,6,7-tetramethyl- and 7-ethyl-1,3-dimethylpyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione ( 9b and 9c , respectively) were isolated in low yields. When ethyl cyanoacetate or malononitrile was used in place of the ketone in the above reaction, 7-amino-6-ethoxycarbonyl- and 7-amino-6-cyano-1,3-dimethylpyrido[2,3-d]-pyrimidine-2,4(1H,3H)-dione ( 14a and 14b , respectively) were obtained in quantitative yields. A plausible mechanism for the formation of bicyclic compounds is discussed.  相似文献   

19.
3,4,4,5-Tetrachloro-4H-1,2,6-thiadiazine was reacted with BnEt3NCl (10?mol%) to give perchloro-9-thia-1,5,8,10-tetraazaspiro[5.5]undeca-1,4,7,10-tetraene (up to 18% yield), 4,5,6-trichloropyrimidine-2-carbonitrile (up to 44% yield) and four minor side products: 2,7-dichlorothiazolo[5,4-d]pyrimidine-5-carbonitrile, 2-(4-chloro-6H-thiazolo[5,4-c][1,2,6]thia-diazin-6-ylidene)malononitrile, 4,8-dichloropyrrolo[2′,1′:2,3]imidazo[4,5-c][1,2,6]thiadiazine-6,7-dicarbonitrile and 4,7-dichloro-[1,2,6]thiadiazino[3,4-b]thiazolo[5,4-e][1,4]diazepin-9(10H)-one. Single crystal X-ray studies support the structures of the minor products. Tentative rationale for the formation of these minor products and the synthesis of 8-bromo-4-chloropyrrolo[2′,1′:2,3]imidazo[4,5-c][1,2,6]thiadiazine-6,7-dicarbonitrile are presented.  相似文献   

20.

The structure of 2-amino-3-carbamoylchromone has been studied by 1D and 2D NMR spectroscopy. Selective hydrolysis of this compound gives 3-carbamoyl-4-hydroxycoumarin, whereas the reactions with acetic anhydride and hydrazines, 2-methyl-4H-chromeno-[2,3-d]pyrimidine-4,5(3H)-dione and 3-aminochromeno[4,3-c]pyrazol-4-ones, respectively.

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