@article { ISI:000288386600095, title = {Probing the furanose conformation in the 2 {\textquoteleft}-5 {\textquoteleft} strand of isoDNA:RNA duplexes by freezing the nucleoside conformations}, journal = {Chemical Communications}, volume = {47}, number = {13}, year = {2011}, month = {FEB}, pages = {4007-4009}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Sugar conformations in the isoDNA strand of isoDNA : RNA duplexes are preferred S-type locked/frozen in contrast to N-type locked conformations preferred in DNA: RNA duplexes.

}, issn = {1359-7345}, doi = {10.1039/c0cc05402j}, author = {Erande, Namrata D. and Gunjal, Anita D. and Fernandes, Moneesha and Kumar, Vaijayanti A.} } @article { ISI:000312946200007, title = {Synthesis and structural studies of S-type/N-type-locked/frozen nucleoside analogues and their incorporation in RNA-selective, nuclease resistant 2 {\textquoteleft}-5 {\textquoteleft} linked oligonucleotides}, journal = {Organic \& Biomolecular Chemistry}, volume = {11}, number = {5}, year = {2013}, month = {NOV}, pages = {746-757}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

2{\textquoteright}-endo locked or frozen (S-type)/3{\textquoteright}-endo locked or frozen (N-type) nucleoside analogues were synthesized. Conformational analysis based on (3)J(HH) and NOE measurements is presented which is further confirmed by X-ray crystal structural studies. 2{\textquoteright}-5{\textquoteright} isoDNA oligonucleotides (ON) were synthesized using these modified nucleoside analogues and UV-T-m studies of the resultant 2{\textquoteright}-5{\textquoteright} isoDNA : RNA duplexes reflect the site-and sequence-dependent effects and confirm that the S-type sugar conformations were preferred over the N-type sugar geometry in such duplexes.

}, issn = {1477-0520}, doi = {10.1039/c2ob26762d}, author = {Erande, Namrata D. and Gunjal, Anita D. and Fernandes, Moneesha and Gonnade, Rajesh G. and Kumar, Vaijayanti A.} } @article { ISI:000328650000032, title = {Functional isoDNA aptamers: modified thrombin binding aptamers with a 2{\textquoteright}-5{\textquoteright}-linked sugarphosphate backbone (isoTBA)}, journal = {Chemical Communications}, volume = {50}, number = {5}, year = {2014}, month = {NOV}, pages = {605-607}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

The regioisomeric 3{\textquoteright}-deoxy-2{\textquoteright}-5{\textquoteright}-linked thrombin binding DNA aptamers (isoTBAs) were chemically synthesized and their ability to form unimolecular anti-parallel G-quadruplexes in the presence of K+ ions was evaluated. These modified sequences retain the function of the native thrombin binding aptamer (TBA), exhibit better stability against exonuclease and are capable of slowing down the process of blood clotting.

}, issn = {1359-7345}, doi = {10.1039/c3cc47569g}, author = {Gunjal, Anita D. and Fernandes, Moneesha and Erande, Namrata D. and Rajamohanan, P. R. and Kumar, Vaijayanti A.} } @article { ISI:000365220100089, title = {Ene-nucleic acids: a different paradigm to DNA chemistry}, journal = {RSC Advances}, volume = {5}, number = {118}, year = {2015}, month = {NOV}, pages = {97824-97830}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Acyclic prochiral nucleic acids such as FNA, UNA, GNA and cyclic chiral TNA are all considered as precursors of DNA and RNA in the chemical etiology of nucleic acids. The chemical reasoning would suggest that unsaturated precursors with constrained flexibility and selectivity based on cis/trans isomers could be the missing link between the prochiral-acyclic and chiral-cyclic structures mentioned above. We find that ene-nucleic acids derived from an isoprenoid skeleton possess requisite flexibility and rigidity while forming stable duplex structures with complementary DNA and RNA.

}, issn = {2046-2069}, doi = {10.1039/c5ra15673d}, author = {Varada, Manojkumar and Erande, Namrata D. and Kumar, Vaijayanti A.} } @article {42435, title = {Unimolecular antiparallel G-quadruplex folding topology of 2{\textquoteright}-5{\textquoteright}-isoTBA sequences remains unaltered by loop composition}, journal = {Organic \& Biomolecular Chemistry}, volume = {13}, year = {2015}, month = {OCT}, pages = {11696-11703}, type = {Journal Article}, abstract = {

A 2{\textquoteright}-5{\textquoteright}-linked isoTBA 15 mer sequence with (232) loop composition formed stable antiparallel quadruplex structures similar to the SELEX derived 15 mer TBA sequence with (232) loop composition. A parallel versus antiparallel topology of 3{\textquoteright}-5{\textquoteright}-G-quadruplexes is largely dictated by the loop length, and it is known that the truncated loops favour parallel quadruplexes. In contrast to TBA, systematic reduction of the loop length in isoTBA from (232) to (222), (131) or even (111) did not alter the antiparallel topology of the resulting 14 mer, 13 mer and 11 mer G-rich modified isoTBA-like sequences.

}, doi = {10.1039/c5ob01923k}, author = {Aher, Manisha N.}, editor = {Erande, Namrata D.} } @article {46909, title = {Influence of fluorine substitution on the molecular conformation of 3 {\textquoteleft}-deoxy-3 {\textquoteleft}-fluoro-5-methyluriaine}, journal = {Acta Crystallographica Section C-Structural Chemistry}, volume = {76}, year = {2020}, month = {APR}, pages = {346+}, type = {Article}, abstract = {

{Fluorine substitutions on the furanose ring of nucleosides are known to strongly influence the conformational properties of oligonucleotides. In order to assess the effect of fluorine on the conformation of 3{\textquoteright}-deoxy-3{\textquoteright}-fluoro-5-methyluridine (T-R(F)), C-10 H13FN2O5, we studied its stereochemistry in the crystalline state using X-ray crystallography. The compound crystallizes in the chiral orthorhombic space group P2(1)2(1)2(1) and contains two symmetry-independent molecules (A and B) in the asymmetric unit. The furanose ring in molecules A and B adopts conformations between envelope (E-2, 2{\textquoteright}-endo

}, keywords = {crystal structure, fluoro nucleoside, pseudorotation parameter, sugar puckering, uridine}, issn = {2053-2296}, doi = {10.1107/S2053229620003083}, author = {Aher, Manisha N. and Erande, Namrata D. and Kumar, Vaijayanti A. and Fernandes, Moneesha and Gonnade, Rajesh G.} }