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Equilibrium and Thermodynamic Studies of Ternary Systems Involving Metal Ions, N-(2-Acetamido)iminodiacetic Acid and Pyrimidine Bases

Ahmed I., Boraei A., Soliman E.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 12

1861-1872

EN

Complex formation in the ternary systems: Mn+ + N-(2-acetamido)iminodiacetic acid (H2ADA) + some pyrimidine bases of nucleic acid (HL) [thymine, thymidine and uracil], where Mn+ = CuII, ZnII, NiII, CoII, CdII, PbII, UO2 II, and CeIII have been investigated pH-metrically. The thermodynamic functions deltaH, deltaG, deltaS) associated with the complex formation of [NiII-N-(2-acetamido)iminodiacetic acid - thymine or uracil] were also calculated and discussed.

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On the Chemistry of Cinnoline III : Condesation Reactions of (4-Amino-cinnolin-3-yl)-phenyl-methanone and 4-Amino-3-cinnoline-carbonitrile

Amer A., Attia I., El-Mobayad M., Asker S.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 5

681-686

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Molecular Recognition of Pyrimidine and Xanthine Bases by Lipophilic Calixarenes Derived from Resorcinol and Pyrogallol

Pietraszkiewicz O., Brzózka Z., Pietraszkiewicz M.

Polish Journal of Chemistry

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1999

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Vol. 73, nr 12

2043-2052

EN

Two lipophilic calixarenes, derived from resorcinol (R1) and pyrogallol (R2), were investigated as receptors for pyrimidine and xanthine bases in extraction experiments. Extraction abilities sequence for R1 in chloroform is: cytosine>uracil>thymine, whereas for R2: thymine>uracil>cytosine. Among pyrimidine bases, no clear pattern of extraction was observed: uracil was extracted most effectively to toluene phase, thymine - into diethyl sebacate, cytosine into - chloroform.

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Metody syntezy siarkowych pochodnych zasad pirymidynowych

Nowakowska Z., Wyrzykiewicz E.

Wiadomości Chemiczne

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1998

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[Z] 52, 5-6

449-466

EN

Uracil thio-derivatives have become to play increasingly important roles in biology and medicine. Numerous sulphur-substituted pyrimidines have found applications as clinically useful drugs. Thiouracils have recently been the subject of considerable interest as they inhibit hyperthyroidism in man [1, 2], have been isolated from E. Coli tRNA [3], and inhibit virus [4] and bacterial growth [5] by causing alterations [6] in protein synthesis. Thiouracils are also of interest because of mutagenic [7], anticancer and antithyroid activity [8], kidney stone formation inhibition [9] and antidote properties for mercury poisoning . Two of them, 2-thiouracil and 6-propyl-2-thiouracil, exhibit marked affinities for melanin-producing tissue in vitro and a similar affinity in vivo, where they presumably act as false precursors for melanin [10, 11]. Boron-containing derivatives of thiouracils [12-14] containing a dihydroxyboryl (or 1-o-carboranylalkyl) group in the 5-position are very important because of their potential applications for BNCT. Human immunodeficiency virus type 1 (HIV-1) is the causative agent of acquired immunodeficiency syndrome (AIDS), which is one of the world's most serious health problems. Since the discovery of the acyclic 6-substituted uridine derivative 1-[(2-hydroxyethoxy0methyl]-6-(phenythio)-thymine (HEPT) as a novel lead for specific anti-HIV-1 agents [15], a number of HEPT analogs have been synthesized to increase its potency [16-18]. The studies of the structure-activity relationships of HEPT analogs indicated that replacement of the 2-oxo function with a thine function potentiated their anti-HIV-1 activity [16, 19, 20]. Therofore the synthesis of thio-substituted pyrimidine bases and their derivatives appears to be a challenge for organic chemists. The methods of preparation of these compounds have been reviewed.