A-deoxyadenosine

Figure 24. Comparison of the structures of (a) deoxyadenosine and (b) an alkylated derivative. Note the syn conformation of the product of alkylation.

A-residue, G-residue etc. or more simply dA, dG (or A, G etc. where there is no possibility of confusion with the ribonucleotides, for example as in a DNA sequence) pdT etc. dTMP, dAMP etc. rATP, rCTP etc. A deoxyadenosine (deoxyguanosine) monophosphate either at one end, or within, a polynucleotide chain and linked to the adjacent nucleotide(s) by phosphodiester bond(s) deoxythymidine 5 -monophosphate the deoxynucleoside 3 -monophosphate the ribonudeoside triphosphates, adenosine triphosphate, cytidine triphosphate etc. 

Adenine (A) Deoxyadenosine Guanine (G) Deoxyguanosine Thymine (T) Thymidine Cytosine (C) Deoxycytidine Deoxyadenylate (dAMP) Deoxyguanylate (dGMP) Thymidylate (TMP) Deoxycytidylate (dCMP)... 

The PAH benzo[g/z/(fluoranthene (35) undergoes metabolism to an epoxide (36) which can form adducts with DNA, for example, by binding to a deoxyadenosine residue (equation 1). In Section V.A the structure of four possible diastereoisomers of the deoxyadenosine adduct (37) is discussed29. 

S addud derived from truns addition of a deoxyadenosine fZ-amino group to (+)-(7R,8S,9S,10R)-7,8-dihydroxy-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a] pyrene an unusual syn glycosidic torsion angle at the modified dA. Biochemistry, 34, 13570-13581. 

In a stereocontrolled synthesis of oligodeoxyribonucleoside phosphorothioates, the monomers (99) were prepared from the cyclic thiophosphoramidite (100) as shown. The preparation of a deoxyadenosine 3 -5-thiophosphoramidite (101) has been described, and its use to obtain a... 

Ide H, Shimzu H, Kimura Y, Sakamoto S, Makino K, Glackin M, Wallace SS, Nakamuta H, Sasaki M, Sugimoto N (1995) Influence of a-deoxyadenosine on the stability and structure of DNA. Thermodynamic and molecular mechanics studies. Biochemistry 34 6947-6955... 

The numbering scheme used for nucleosides maintains the independence of the two structural units The pyrimidine or purine is numbered m the usual way So is the car bohydrate except that a prime symbol ( ) follows each locant Thus adenosine is a nude oside of D nbose and 2 deoxyadenosine is a nucleoside of 2 deoxy d ribose... 

Amino-2 -deoxypurines. 2 -AmiQo-2 -deoxyadenosine (15) is a naturally occurring A[-nucleoside isolated from A.ctinomadura that shows antknycoplasmal activity (1,4). Adenosine is the direct precursor for its biosynthesis (30). 2 -Arnino-2 -deoxyguanosine (16), isolated from a strain of Enterobacter cloacae (1,4), shows the growth of HeLa S3 cells and Sarcoma 180 in vivo and has been tested for antibacterial activity. 

Pentostatin (deoxycoformycin Fig. 4) is a purine isolated from cultures of Streptomyces antibioticus. Its mode of action involves inhibition of adenosine deaminase, which plays a key role in purine salvage pathways and DNA synthesis. As a consequence, deoxyadenosine triphosphate (dATP) is accumulated, which is highly toxic to lymphocytes. This is associated with augmented susceptibility to apoptosis, particularly in T cells. 

CN cobinamide Co-(5 -deoxyadenosine-5 ) de riv. hydroxide dihydrogen phosphate (ester) inner salt 3 -ester with 5,6-dimethyl-1 -a-D-ribofuranosyl-1 //-benzimidazole... 

A method has been reported for the quantification of the DNA oxidation products, 8-hydroxy-2 -deoxyguanosine (8-OH-dG), 8-hydroxy-2 -deoxyadenosine (8-OH-dA), 5-hydroxymethyl-2-deoxyuridine (HMDU), thymidine glycol (TG) and 2-hydroxy-2 -deoxyadenosine (2-OH-dA) [37], The HPLC system employed consisted of a 2.0 X 250 mm Cig column and gradient elution from waterimethanol, (94 6) to (10 90) over 28 min, at a flow rate of 200 tilmin ... 

Palom, Y. Lipman, R. Musser, S. M. Tomasz, M. A mitomycin-A-6-deoxyadenosine adduct isolated from DNA. Chem. Res. Toxicol. 1998, 11, 203-210. 

Adenosine deaminase (ADA) is an amino hydrolase that catalyzes the deamination of adenosine and 2 -deoxyadenosine to inosine and 2 -deoxyinosine, respectively. High activity of ADA is seen in thymus and other lymphoid tissues. ADA has been shown in many different physical forms. A small form of the enzyme predominates in the spleen, stomach, and red blood cells, whereas the large form predominates in the kidney, liver, and skin fibroblasts. The small form of the catalytic subunit can be converted to the large form by complexing with a protein termed binding protein or complexing protein. 

Methylmalonyl-CoA mutase (MCM) catalyzes a radical-based transformation of methylmalonyl-CoA (MCA) to succinyl-CoA. The cofactor adenosylcobalamin (AdoCbl) serves as a radical reservoir that generates the S -deoxyadenosine radical (dAdo ) via homolysis of the Co—C5 bond [67], The mechanisms by which the enzyme stabilizes the homolysis products and achieve an observed 1012-fold rate acceleration are yet not fully understood. Co—C bond homolysis is directly kineti-cally coupled to the proceeding hydrogen atom transfer step and the products of the bond homolysis step have therefore not been experimentally characterized. 

Gustavsson T, Sharonov A, Onidas D, Markovitsi D (2002) Adenine, deoxyadenosine and de-oxyadenosine 5 -monophosphate studied by femtosecond fluorescence upconversion spectroscopy. Chem Phys Lett 356 49... 

Gaied NB, Glasser N, Ramalanjaona N, Beltz H, Wolff P, Marquet R, Burger A, Mly Y (2005) 8-vinyl-deoxyadenosine, an alternative fluorescent nucleoside analog to 2 -deoxyribosyl-2-aminopurine with improved properties. Nucl Acids Res 33 1031-1039... 

Ethanolamine ammonia lyase has a molecular weight of 520,000 and consists of 8 or 10 subunits. Two 5 -deoxyadenosylcobalamin molecular bind per enzyme molecule, and recent kinetic studies by Babior show that these two molecules carry out catalysis independently. Evidence is available that this enzyme functions by a radical mechanism since both spin labeling and Co(II) esr experiments indicate that Co(II) is an intermediate during H-transfer. Also, 5 -deoxyadenosine has been detected as a product of oxygenation of the enzyme-substrate complex (99—101). 

A cyclic nucleotide, 2, 3 -bis(2-chloroethyl)aminophosphoryl-3 -amino-3 -deoxyadenosine (139) showing antitumor activity, was prepared in 40% yield starting from 3 -amino-3 -deoxyadenosine 133 by its phosphorylation with N,N-bis-(2-chloroethyl) amidophosphoryl dichloride 138. Both P-diastcrcomers separated by column chromatography exhibit activity against KB tumor cell cultures (Scheme 40) [71]. 

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