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Density functional theory (DFT) methods are used to study the influence of N7 protonation on the mechanism of the N-glycosidic bond hydrolysis in 2'-deoxyguanosine. The results have shown that protonation of guanine strongly catalyzes the hydrolysis of the N-glycosidic bond by making the nucleobase a better leaving group.

Various methodologies are employed to study the structure and stereochemistry of the four interconverting diastereomers of N'-carbamoyl-4,5-dihydroxy-2-oxoimidazolidine nucleosides, which are formed on the oxidation of 2'-deoxycytidine. The analysis demonstrates a linear increase in the rate of the isomerization with an increase in the pH.

The reactions of the anticancer complex trans-[PtCl2{(E)-HN=C(OMe)Me}2] (trans-EE) with a series of ribo and deoxyribodinucleotides are studied by HPLC as 2D [1H, 15N] HMQC NMR spectroscopy and compared with those of the inactive trans isomer of cisplatin. This investigation demonstrated that trans-oriented D complexes are capable of forming 1,2-bifunctional adducts with single-strand oligonucleotides.

An effective Pd/Cu-mediated direct arylation of 2'-deoxyadenosine with various aryl iodides to obtain 8-arylated 2?-deoxyadenosine derivatives in good yields optimized by a a substoichiometric quantity of piperidine (secondary amine) in combination with cesium carbonate is described. The unique Pd/Cu catalyst system could be applied for reaction of adenosine type substrates, with the reactivity similar to that observed in direct arylations of related [super 1]H-imidazoles.

A series of dGTP bisphosphonate analogues in which the [beta], [gamma]-bridging oxygen was replaced by a series of substituted methylene groups was used to probe leaving group effects on nucleotidyl transfer and develop an alternative strategy to explore the fidelity and mechanism of DNA polymerases. The amplified differences observed between the linear free energy relationship (LFER) lines for the incorporation of matched and mismatched deoxynucleotides that probably reflected the differences in the electrostatic interaction between the TS charges in the polymerase active site could offer insight into the factors governing the fidelity of DNA polymerases.

Two approaches are described for preparing of 2'-C-[beta]-methyl-2'-deoxyguanosine via 2'-radical deoxygenation. First approach has started from 1,3,5-tri-O-benzoyl-[alpha]-D-ribofuranose and the second approach has started from guanosine.

A two-step approach is described for preparing 2E-deoxytetrahydrouridine (dTHU) in increased yields and purity. Catalytic reduction of 2E-deoxyuridine, followed by reduction with sodium borohydride as a limiting reagent, has produced dTHU and has limited formation of side products.

Rational design and combinatorial protein engineering are used for the systematic exploration of the impact of active site mutations on the catalytic performance of human deoxycytidine kinase (dCK). The results have shown the main contributions of the two amino acid positions to enzyme function by highlighting their ability to moderate substrate specificity.

The crystal structure of human cytosolic 5'(3')-deoxyribonucloetidase (cdN) and mitochondrial 5'(3')-deoxyribonucleotidase (mdN) enzymes was studied to understand their substrate specificity as nucleotide analogues. The findings could be used for future development of catabolically stable nucleotide-based drugs.

The structure investigation of human deoxyhemoglobin A (deoxy-Hb A) is carried out in solution in the absence and presence of inositol hexaphosphate (IHP) by using the measurements of the magnetic-field-induced [super 1]H-[super 15]N residual dipolar couplings (RDCs). The results have helped in understanding the structure-function relationship of the allosteric protein.

The 6-Azauridine 5'-monophosphate is a strong inhibitor of enzyme orotidine 5'-monophosphate decarboxylase. Such oligodeoxyribonucleotides containing the nucleoside 6-aza-2'-deoxyuridine are prepared by using solid phase synthesis.

2-Hydroxy-2'-deoxyadenosine 5'-triphosphate and 8-hydroxy-2'-deoxyguanosine 5'-triphosphate complexes are used to study the coexistent effects of the multiple kinds of oxidized deoxyribonucleotides. The results show that one complex enhances the A.T - C.G mutations caused by the other complex by suppressing its degradation upon replication in a HeLa extract.

The reaction mechanism of human deoxyribonucleotidase (dN) is studied using high-level quantum-chemical methods. dN catalyzes the dephosphorylation of deoxyribonucleoside monophosphates to their nucleoside form in human cells.

The ability of Taq DNA polymerases to incorporate and efficiently continue DNA synthesis beyond the oxadiazole carboxamide nucleobases is described. The results highlight that different selection rules are utilized by DNA polymerases during the incorporation and extension steps to avoid mismatches.