Adenine nucleosides

Desaubry L, Shoshani I, Johnson RA (1996) Inhibition of adenylyl cyclase by a family of newly synthesized adenine nucleoside 3 -polyphosphates. J Biol Chem 271 14028-14034... 

Figure 2. Reaction Mechanism for N-Sulfonyloxy Arylamides (I). Ac, acetyl RSCHs, methionine RSH, glutathione or cysteine RNH2, N2-guanine- and/or N6-adenine-nucleosides, -nucleotides, or -nucleic acids RCH, C8-guanine-nucleosides, -nucleotides, or -nucleic acids, or C7-AAF.

Grouped in this Section are the C-D-pentofuranosyl-imidazoles, -pyrazolopyrimidines, and -adenines. The last two analogs are positional isomers of formycin in which the heterocyclic moiety is attached to the sugar at an unnatural position. A rationale103 for the synthesis of this type of analog is of interest it was based on the possibility of a close structural similarity between a natural adenine nucleoside and synthetic analog with respect to available hydrogenbonding sites. 

Nucleocidin (LXXX) [353], an adenine nucleoside antibiotic whose structure has recently been elucidated, is also a potent inhibitor of protein synthesis. Studies with this compouna have led to the conclusion that nucleocidin forms a complex with ribosomes which is inactive in peptide bond formation. Binding... 

Figure 9. Synthesis of a bicyclic adenine nucleoside related to the octosyl acids.

Vidarabine (adenine arabinoside, Vira-A) is an adenine nucleoside analogue containing arabinose in place of ri-bose. It is obtained from cultures of Streptomyces an-tibioticus and has activity against HSV-1, HSV-2, VZV, CMV, HBV, poxviruses, hepadnaviruses, rhabdoviruses, and certain RNA tumor viruses. 

Toxicity. Atractyloside, a diterpenoid glycoside that occurs naturally in plants, may be present at levels as high as 600 mg/kg of dried plant material. Gonsumption of plants containing atractyloside or carboxyatractyl-oside has caused fatal renal proximal tubule necrosis and/or centrilobular hepatic necrosis in man and farm animals. Although pure atractyloside and crude plant extracts disrupt carbohydrate homeostasis and induce similar pathophysiological lesions in the kidney and liver, it is also possible that the toxicity of atractyloside may be confounded by the presence of other natural constituents in plants. Atractyloside competitively inhibits the adenine nucleoside... 

Adenine nucleosides from 145 (Ref. 287) and 85 (R = CH2OH, R1 = R2 = H),405 and l-[3-deoxy-3-fluoro-3-C-(hydroxymethyI)-a,/ -D-xylo-furanosyl]uracil,412 were also synthesized. The last two showed no activity versus herpes-1 (HF) virus or L-1210 cells. 

Analogues of vitamin Bi2 are known in which the dimethylbenzimidazole is replaced by other bases it is 5-hydroxybenzimidazole in Factor III, adenine in pseudo-vitamin Bj2, 2-methyladenine in Factor A and 2-methylhypoxanthine in Factor H. Where adenine units occur, they are linked to ribose through position 7, rather than position 9 as in other adenine nucleosides. 

Tchilibon S, Joshi BV, Kim SK, Duong HT, Gao ZG, Jacobson KA (2005) (N)-Methanocarba 2, N6-disubstituted adenine nucleosides as highly potent and selective A3 adenosine receptor agonists. J Med Chem 48(6) 1745-1758... 

Campbell JM, von Sonntag C, Schulte-Frohlinde D (1974) Photolysis of 5-bromouracil and some related compounds in solution. Z Naturforsch 29b 750-757 Candeias LP, Steenken S (1989) Structure and acid-base properties of one-electron-oxidized deoxy-guanosine, guanosine, and 1-methylguanosine. J Am Chem Soc 111 1094-1099 Candeias LP, Steenken S (1992a) Electron adducts of adenine nucleosides and nucleotides in aqueous solution protonation at two carbon sites (C2 and C8) and intra- and intermolecular catalysis by phosphate. J Phys Chem 96 937-944... 

A number of vasodilators, such as acetylcholine, bradykinin, adenine nucleosides, thrombin, histamine, and serotonin, require an intact vascular endothelium to exert their effects. For example, stimulation of endothelial cholinergic receptors causes the release of endothelium-derived relaxing... 

The data suggest that the microenvironment about the N-7 site of adenine nucleosides is dramatically altered after complexation. It was concluded from this work that in complexes with 6-cyclodextrins, the purine residue was oriented in the complex with its short axis nearly parallel to the long axis of the cyclodextrin cavity. 

The adenine nucleoside antibiotic sinefugin (54), first isolated from S. griseolus has now been synthesized free from its C-6 epimer (Scheme 29) (83JA7638). The compound has a variety of... 

---