2 -Deoxy-adenosin

The analogons deamination reaction is not observed in l-methyl-2 -deoxy-adenosine nncleosides. ° Rather, in the adenine series, the Dimroth rearrangement occnrs (Scheme 8.4). On the contrary, in styrene adducts of 2 -deoxyadenosine, the hydroxyl residue of the adduct undergoes intramolecular reaction with the base to initiate deamination (Scheme 8.6). ° ° Similarly, cytosine residues bearing styrene adducts at the N3-position undergo rapid deamination (nearly complete deamination is seen within 75h). °°... 

RaitVK, Zhang Q,Fabris D,et al. Conversions of formaldehyde-modified 2 -deoxy-adenosine 5 -monophosphate in conditions modeling formalin-fixed tissue dehydration. I. Histochem. Cytochem. 2006 54 301-310. 

A photoreactive nucleotide, 8-bromo-2 -deoxy-adenosine, was incorporated post-synthetically into a DNA sequence (35, Fig. 13) within the previously determined DNA contact site for the transcription factor. Upon irradiation the resulting nitrene cross-linked primarily to the 50-kDa subunit and covalently modified Lys-244. On the other hand, that amino acid residue appeared not... 

Zur selektiven Entfernung von N-Benzoyl-Gruppen bei Vorhandensein von O-Benzoyl-Gruppen, z. B. in der Nukleosid-Chemie, laBt sich die Kombination Bortrifluorid/Zink-bromid verwenden, wie nachstehend fur die N-Debenzoylierung von 3, 5 -0,0,NH-Tri-benzoyl-2 -deoxy-adenosin zu 3, 3 -0,0-Dibenzoyl-2 -deoxy-adenosin (93%) formuliert3 ... 

P 2 -deoxyadenosine 5 -diphosphate + trans-farnesyl triphosphate S 2 -deoxy-adenosine 5 phosphate -I- trans-farnesyl diphosphate <1> (<1>... 

The mercury derivatives procedure has also been applied to deoxynucleosides. 2 -Deoxy-adenosine and its a-D-anomer are obtained, after deblocking, from the AT-glycosylation of chloromercurio-7V -benzyladenine with crystalline 2-deoxy-3,5-di-0-(4-toluoyl)- -D-ribofura-nosyl chloride. 

The synthesis and incorporation into oligonucleotides of the A-phosphory-lated deoxycytidine 3 -phosphoramidites (144) and (145) obtained either from the O-protected 2 -deoxycytidine and bis(2-cyanoethyl) A,A-diisopropyl phosphoramidite or diethylphosphorochloridite, respectively, was described by Sekine. Sekine also reported that the A-phosphorylated derivatives of 2 -deoxy adenosine decomposed readily and were unsuitable for incorporation into oligodeoxynucleotides. 

Chemical transformations of nucleosides have resulted in the syntheses of some 2, 3 -unsaturated pyrimidine nucleosides as well as a 4, 5 -unsaturated pyrimidine nucleoside. Treatment of 3 -O-tosyl-2 -deoxy-adenosine with alkoxide produced the 2, 3 -unsaturated nucleoside as well as a smaller amount of the 3, 5 -oxetane derivative. The syntheses of 2, 3 -dideoxy-, 2, 5 -dideoxy-, and 2, 3, 5 -trideoxyadenosine have been accomplished by mono- or ditosylation of 2 -deoxyadenosine... 

N6-Ethenoderivatives of adenosine (2 -deoxy adenosine) may be obtained as metabolites from the reaction of DNA with vinyl chloride, chloroacetaldehyde or chloroethylenoxide [321]. Excitation wavelength of such heterocycles is 300 nm with a maximum of emission at 412 nm. Phosphoramidite (131) and similar compounds have been incorporated into oligonucleotides [322-324],... 

The acyclic nucleoside phosphonate, 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA), also known as Adefovir [1], can be considered as an analogue of (2 -deoxy)adenosine 5 -monophosphate ((d)AMP ) [2]. PMEA has excellent antiviral properties [1] and in the form of its bis(pivaloyloxymethyl)ester, Adefovir dipivoxil, it has recently been approved by the US Food and Drug Administration (FDA) for the treatment [3] of hepatitis B patients these people suffer from an infection of aDNAvirus. 

Potentiometric and spectroscopic titrations of deoxyribonucleosides, dA (= 2 -deoxy-adenosine), dG (= 2 -deoxyguanosine), dC (= 2 -deoxycytidine), and dT (= thymidine), and related compounds in the presence of 8 disclosed extremely selective 1 1 binding of 8 to dT... 

In a new approach to carbocyclic 2 -deoxyribonucleosides, intermediate 159, produced in chiral form by enzymic resolution, was converted to its bicyclic sulfate by interaction with SOCI2 followed by oxidation the sulfate was then linked with an appropriate base unit to give the analogues 160 of 2 -deoxy-adenosine and -guanosine together with the 2,6-diaminopurine... 

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