- Towards a Molecular Understanding of Cation-Anion Interactions and Self-aggregation of Adeninate Salts in DMSO by NMR and UV Spectroscopy and Crystallography
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Rare anionic forms of nucleic acids play a significant biological role and lead to spontaneous mutations and replication and translational errors. There is a lack of information surrounding the stability and reactivity of these forms. Ion pairs of mono-sodium and -potassium salts of adenine exist in DMSO solution with possible cation coordination sites at the N1, N7 and N9 atoms of the purine ring. At increasing concentrations π-π stacked dimers are the predominant species of aggregates followed by higher order aggregation governed by coordination to metal cations in which the type of counter ion present has a central role in the aggregate formation.
- Buyens, Dominique M. S.,Pilcher, Lynne A.,Roduner, Emil
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- Conformationally restricted nucleocyclitols: A study into their conformational preferences and supramolecular architecture in the solid state
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With the intent of probing the feasibility of employing annulation as a tactic to engender axial rich conformations in nucleoside analogues, two adenine-derived, "conformationally restricted" nucleocylitols, 9 and 10, have been conceptualized as representatives of a hitherto unexplored class of nucleic acid base-cyclitol hybrids. A general synthetic strategy, with an inherent: scope for diversification, allowed, rapid functionalization of indane and tetralin to furnish 9 and 10 respectively in fair yield. Single-crystal X-ray diffraction analysis revealed that the two nucleocyclitols under study, though homologous, present completely dissimilar modes of molecular packing, marked, in particular, by the nature of involvement of the adenynyl NH 2 group in the supramolecular assembly. In addition, the crystal structures of 9 and 10 also exhibit two different conformations of the functionalized cyclohexane ring. Thus, while the six-membered carbocycle in cyclopenta-annulated 9 exists in the expected chair (C) conformation that in cyclohexaannulated 10, which crystallizes as a dihydrate, shows an unusual twist-boat (TB) conformation. From a close analysis of the 1HNMR spectroscopic data recorded, for 9 and 10 in CD3OD, it was possible to put forth a putative explanation for the uncanny conformational preferences of crystalline 9 and 10. Wiley-VCH Verlag GmbH & Co. KGaA.
- Mehta, Goverdhan,Talukdar, Pinaki,Pullepu, Venkatesh,Sen, Saikat
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- PREVENTION AND TREATMENT OF CANCER AND OTHER DISEASES
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Nucleoside chemical compounds, which interact with specific structures of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) are disclosed. The compounds interfere with the activities of telomerase and reverse transcriptase, and are useful as antivirals, antibacterials and anticancer agents. Methods of treating or preventing cancers in patients involving administration of a therapeutically effective amount of a composition having an inhibitor or antagonist of the reverse transcriptases (RTs) expressed in cells of the patients are also disclosed. Method of using nucleoside analogs and other inhibitors of RTs in conjunction with DNA damaging agents such as genotoxic agents or radiation or photodynamic therapy or combinations these for the treatment of various cancers are also disclosed.
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Page/Page column 61; 66; 72
(2008/06/13)
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- Organization of microcrystals on glass by adenine-thymine hydrogen bonding
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Shaking of adenine-tethering glass plates in an aqueous suspension of micrometer-sized, thymine-tethering zeolite crystals such as ZSM-5 (0.6 μm × 1.7 μm × 2.5 μm) or zeolite-A (1.7 μm × 1.7 μm × 1.7 μm) for 3 h at room temperature leads to facile assembly of monolayers of the zeolite microcrystals on the glass plates through the hydrogen-bonding interaction between the tethered adenine and thymine. Control experiments show that the presence of adenine and thymine on the respective solid surface is essential for the monolayer assembly. This establishes that even the micrometer-sized building blocks can be organized by a large number of well-defined weak hydrogen bonding. Increase in the assembly temperature to annealing temperatures leads to a marked increase in the rate of monolayer assembly and in the size of the domain in which zeolite crystals are closely packed in the same three-dimensional orientation. Copyright
- Park, Jin Seon,Lee, Goo Soo,Lee, Yun-Jo,Park, Yong Soo,Yoon, Kyung Byung
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p. 13366 - 13367
(2007/10/03)
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- 2-hydroxymethylcyclopropylidenemethylpurines and -pyrimidines as antiviral agents
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Compounds which are active against viruses have the following Formulas: wherein B is a purine or pyrimidine heterocyclic ring and is preferably selected from the group consisting of 6-aminopurine (adenine), 2,6-diaminopurine, 2-amino-6-azidopurine, 2-amino-6-cyclopropylaminopurine, 6-hydroxypurine (hypoxanthine), 2-amino-6-halo substituted purines, 2-amino-6-alkoxy substituted purines, 2-amino-6-hydroxypurine (guanine), 3-deazapurines, 7-deaza-purines, 8-azapurines, cytosine, 5-halo substituted cytosines, 5-alkyl substituted cytosines, thymine, uracil and 6-azapyrimidines; X is O; and, R1 and R2 are alkyl or aryl groups. The compounds of the present invention also include the R- and S-enantiomers of the above compounds. The R1X and/or R2X can also be amino acid residues with X as NH.
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Page column 10
(2008/06/13)
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- Process for preparing 2'-deoxy-β-adenosine
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2'-deoxy-β-adenosine can be industrially and easily obtained without using expensive or dangerous materials by the process of the present invention, which comprises the steps of: preparing a salt of adenine from adenine, allowing to condense the salt with a derivative of pentofuranose to isolate a derivative of adenine, and then eliminating the protecting groups.
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- THE SYNTHESIS OF 2'-DEOXYADENOSINE VIA STEREOSPECIFIC COUPLING REACTION
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The coupling reaction of the sodium salt of adenine, which could be easily prepared by deprotonation with sodium hydroxide or sodium methoxide, with 1-α-chloro-2-deoxyribose derivative proceeded in a good stereospecific manner in acetone as a solvent to give the β-anomer of the corresponding acylated adenosine.
- Kawakami, Hiroshi,Matsushita, Hajime,Naoi, Yoshitake,Itoh, Kazuo,Yoshikoshi, Hajime
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p. 235 - 238
(2007/10/02)
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- Titanocene derivatives of purine and adenine. Synthesis and characterization of reaction products with (η5-C5H5)2Ti(CO)2, (η5-C5H5)2TiCl, and (η5-C5H5)2TiCl2
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The reaction of CpTi(CO)2 (1), Cp2TiCl (2), and Cp2TiCl2 (3) (Cp = η5-C5H5) with purine (PuH) and adenine (AdH) in organic solvents is described.The compound 1 reacts with both molecules in an oxidative fashion giving Cp2Ti(C5H3N4)(C5H4N4) (4) and (Cp2Ti)2(C5H3N5) (5) with concomitant liberation of molecular carbon monoxide and hydrogen (4:1) following a first order rate law in metal complex.The compound 2 forms an adduct compound Cp2TiCl(C5H4N4) (6) with PuH.Monosubstituted derivatives Cp2TiCl(C5H3N4) (7) and Cp2TiCl(C5H4N5) (8) are formed from the reaction of the deprotonated bases with 3.In addition to the usual elemental analysis, the characteristic ir, 1H nmr, epr, and ms results are given for the new compounds.
- Cozak, Daniel,Mardhy, Abdelhakim,Morneau, Andre
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p. 751 - 759
(2007/10/02)
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- Purine derivatives
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Purines and pyrimidines having a fused cyclopropane ring in the side chain and the heterocyclic isosteres of said purines and pyrimidines have antiviral activity, especially against viruses of the herpes class.
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