Purine Metabolism in Tetrahymena and Its Relation to Malignant Cells in Mice

Pyridazine nucleosides. The structure and conformational analysis of 5-hydroxy-2-(1-β-D-ribofuranosyl)-3(2H)-pyridazinone

“…Certain modifications of the bases and corresponding nucleosides and nucleotides of ribonucleic acids (RNA) and deoxyribonucleic acids (DNA) have proven to possess very interesting biological and chemotherapeutic properties (Skoda, 1963;Roblin, Lampen, English, Cole & Vaughan, 1945;Kidder, Dewey, Parks & Woodside, 1949;Montgomery, Elliot & Thomas, 1975). The differences in activity between the naturally occurring bases and the modified bases are due in part to the structural changes and in part to the electronic effects brought about by the various modifications.…”

Synthesis and regioselective N- and O-alkylation of 3-alkyl-5-phenyl-3H-[1,2,3]triazolo[4,5-d]pyrimidin-7(6H)-ones and 2-phenyl-9-propyl-9H-purin-6(1H)-one with evaluation of antiviral and antitumor activities

“…The absence of the alcoholic absorption band in the IR spectra as well as the broad singlet signal attributable to the alcoholic OH proton in the 1 H NMR spectra of these two derivatives 6 and 7 showed the substitution of hydroxyl group to chlorine. When the dichlorinated derivatives 6 and 7 were treated with sodium methoxide in methanol at room temperature, the nucleophilic substitution took place only at the 7-position to give the corresponding 3-(2-chloroethyl)-7-methoxy-8 and 3-(3-chloropropyl)-7-methoxy-5-phenyl-3H- [1,2,3]triazolo [4,5-d]pyrimidine 9 in 81% and 88% yields, respectively. 1 H NMR spectra of these two methoxy derivatives showed only one singlet signal (δ 4.38) attributable to the 7-O-methyl protons, which was consistent with the other 7-O-methyl derivatives (δ 4.37-4.40 for 4a-g).…”

“…[1][2][3][4][5] Particular interests are the structural modification of purine bases as well as introduction of different functional groups into these bases in the view of searching potential antineoplastic and antiviral agents. Introduction of different functional groups, e.g., amino, oxo, thioxo, alkylthio, alkyl/aryl groups, into purine bases at different positions has been assessed for potency and selectivity for the biological system.…”

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Abstract ---3-Alkyl-5-phenyl-3H- [1,2,3]triazolo [4,5-d]pyrimidin-7(6H)-ones were prepared by nitrosative cyclization of the appropriate 5,6-diamino-2-phenylpyrimidin-4(3H)-ones with nitrous acid and were subjected to regioselective alkylation with several alkylating agents in aprotic solvent at different temperature. Simultaneous 6-N-and 7-O-alkylations were observed and the regioselectivity varied remarkably with size and shape of the alkylating agents as well as with the reaction temperature.

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Quantification of isomeric equilibria formed by metal ion complexes of 8-[2-(phosphonomethoxy)ethyl]-8-azaadenine (8,8aPMEA) and 9-[2-(phosphonomethoxy)ethyl]-8-azaadenine (9,8aPMEA). Derivatives of the antiviral nucleotide analogue 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA)

“…This nucleobase modification, i.e. the replacement of (C8)H by N [26], was initiated by the more than 50-yearsold discovery of the antibacterial [27] and antitumor [28] properties of 8-azaguanine, which has led to a continued interest in 8-azapurines and related nucleosides [29,30,31,32]. Interestingly, the present study reveals that the metal ion-binding properties of 9,8aPMEA 2À are very similar to those of PMEA 2À whereas the ones of 8,8aPMEA…”