Purines and derivatives

Table 1 Purines and Derivatives Bibliography of Important Publications...

Reviews and major papers dealing with the NMR spectra of purines and derivatives are collected in Table 6. 

Table 19 pXa Values of Some Thioxo(/7)purines and Derivatives ... 

With purine and derivatives [Co(OHy6-C,H,N NH3)] ) 293- 79 11820 4.66 42 sign of 6>p uncertain magnetism determined from Curie-Weiss law 69B40... 

With purine and derivatives [Cu(C5H4N5y ) room 1.74 Gouy 70G21... 

Firefly lucifenn is an example of an azole that contains a benzene ring fused to the five membered ring Such structures are fairly common Another example is benzimidazole present as a structural unit m vitamin B12 Some compounds related to benzimidazole include purine and its ammo substituted derivative adenine one of the so called het erocychc bases found m DNA and RNA (Chapter 28)... 

Purine Nucleoside Derivatives. A number of purine nucleoside analogues are also found to be active against several DNA vimses (Fig. 3). The clinically active antiviral drug ara-A (9-P-D-arabinofuranosyladenine [5536-17-4] vidarabine, 23) is active against a number of DNA vimses in vivo and also inhibits certain RNA tumor vimses which repHcate through a DNA intermediate (43). Ara-A, was first synthesized in 1960 (44) and later... 

Amino groups a to nitrogen are hydrolyzed to the corresponding oxo compounds (as in the purines and pteridines) in bo h acid and alkaline conditions. Schiff bases are reduced to benzylamino derivatives with borohydride. 

Adenine (6-amino purine) and guanine (2-amino-6-oxy purine), the two common purines, are found in both DNA and RNA (Figure 11.4). Other naturally occurring purine derivatives include hypoxanthlne, xanthine, and uric acid (Figure 11.5). Flypoxanthine and xanthine are found only rarely as constituents of nucleic acids. Uric acid, the most oxidized state for a purine derivative, is never found in nucleic acids. 

The examples in the fourth column (Table IX) concern the protonation of purine and adenine and their derivatives while those of the last column mainly reflect Kleinpeter s contributions (Table VIII) to the functional tau-tomerism of 7-hydroxy-l,2,4-triazolo[l,5-a]pyrimidines. 

De Clercq E, Eield H J (2006) Antiviral prodrugs - the development of successful prodrug strategies for antiviral chemotherapy. Brit J Pharmacol 147 1-11 De Clercq E, Hol A, Rosenberg I, Sakuma T, Balzarini J, Maudgal PC (1986) A novel selective broad-spectrum anti-DNA virus agent. Nature 323 464 67 De Clercq E, Sakuma T, Baba M, Pauwels R, Balzarini J, Rosenberg I, Hol A (1987) Antiviral activity of phosphonylmethoxyalkyl derivatives of purine and pyrimidines. Antiviral Res 8 261-272... 

Synthetic analogs of purine and pyrimidine bases and their derivatives serve as anticancer dmgs either by inhibiting an enzyme of nucleotide biosynthesis or by being incorporated into DNA or RNA. 

In a review, Moreland, et aj. (11) reported that thiourea, al-lylthiourea, D-xylulose, sodium diethyldithiocarbamate, L-methionine, n-propyl-di-n-propylthiolcarbamate, twelve 6-(substituted) purines, and two coumarin derivatives stimulated Stri qa seed germination. 

Balzarini J, Perez-Perez M-J, San-Felix A, Velazquez S, Camarasa M-J, De Clercq E. [2, 5 -Bis-0-(tert-Butyldimethylsilyl)]-3 -spiro-5"- [4"-amino-1",2"-oxathiole-2",2"-dioxide) (TSAO) derivatives of purine and pyrimidine nucleosides as potent and selective inhibitors of human immunodeficiency virus type 1. Antimicrob Agents Chemother 1992 36 1073-1080. 

The analytical data obtained, particularly by the PUMA mass spectrometer on board Vega 1 during the flyby, indicate the presence of a large number of linear and cyclic carbon compounds, such as olefins, alkynes, imines, nitriles, aldehydes and carboxylic acids, but also heterocyclic compounds (pyridines, pyrroles, purines and pyrimidines) and some benzene derivatives no amino acids, alcohols or saturated hydrocarbons are, however, present (Kissel and Krueger, 1987 Krueger and Kissel, 1987). 

Another important vitamin is folate, which is required for purine and pyrimidine nucleotide synthesis. Since folate and its derivatives are generally lipo-phobic anions, they do not traverse biological membranes via simple diffusion but rather have to be taken up into the cells by specific transport processes... 

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