Base-pair analogues

Do , Do = PAHAt, P(OR)2 Scheme 2.8 Self-assembly of chiral monodentate to chiral bidentate ligands through complementa hydrogen-bonding on the basis of an A-T base pair analogue for combinatorial asymmetric catalysis. 

Meuwly, M., Muller, A. and Leutwyler. S. (2003) Energetics, dynamics and infrared spectra of the DNA base-pair analogue 2-pyridone 2-hydroxypyridine. Phys. Chem. Chem. Phys., 5, 2663-2672. 

Base-Pair Analogues 2.7-bis-[(dialkylamino- and oxa oligoalkylenimino)-acetylamino]-fluoren-9-ones ( f luoramides 1-5) were prepared via the corresponding 2.7-bis- [(chloroacetyl)-amino]-fluoren-9-one by a procedure described recently (56) see also (57). 

Hereupon, adding to the more static view of those system a more dynamic aspect, it was only a short step to look also for thermotropic behaviour of components, that display interaction activities with nucleic acid bases, so for instance among other base-pair analogues the stereoidal hormones (33,50-55,100-104). 

In this context we spent some interest to the field of viro-, cancero- and immunemodulative compounds (Figures 25 and 26) (56,30,31). especially to the first monomer interferon inducer tilorone (116-119), a fluorenone derivative, fitted with basic ali-phatic terminals. As we took it as a nearly ideal example for a geometric base-pair analogue in the meaning of our conception, we postulated for this... 

Hoffmann,S..Witkowski,W.."Polynucleotide Strand-Analogues" and "Base-Pair Analogues" in Conf,Proc. "Wirkungsmechanismen von Herbiciden und syntheti-schen Wachstumsregulatoren" 1972,RGW-Symp,Halle/S.. GDR... 

The mode of action has been a subject for research for a number of years. While it was originally thought that maleic hydrazide replaced uracil in the RNA sequence, it has been deterrnined that the molecule may be a pyrimidine or purine analogue and therefore base-pair formation is possible with uracil and thymine and there exists the probabiHty of base-pair formation with adenine however, if maleic hydrazide occurs in an in vivo system as the diketo species, then there remains the possibiHty of base-pairing with guanine (50). Whatever the mechanism, it is apparent that the inhibitory effects are the result of a shutdown of the de novo synthesis of protein. 

Many of the mutations caused by artificially produced base analogues are transitions. Mutations are produced by base analogues in one of two different ways. On entering the cell, a base analogue is converted to a nucleoside triphosphate that base pairs, perhaps incorrectly, with a DNA template and is inserted into the nucleotide chain. This is one way in which the mutation can be produced. The other requires an additional round of replication so that an improper base pair forms as a result of the previously incorporated analogue. The result in both cases is a permanently modified DNA. 

The preceding approach can be viewed as an orbital representation analogue for a recently proposed Kohn-Sham-based pair-density functional theory [17],... 

Relatively few simple pyrimidine monomers have been incorporated into heterocyclic polymers (70MI11100). By far the greatest efforts with this ring system have involved polymerizable derivatives of nucleic acid bases and related compounds (81MH1102). The majority of this work has involved the synthesis and free radical polymerization of suitable vinyl- and acrylic-functional monomers, e.g. (134)-(136), although epoxy and other derivatives have also been studied. A number of the polymers exhibit base-paired complex formation with natural nucleic acid polymers or synthetic analogues, have found use in... 

Nucleoside analogues do not always behave as expected. 5-Bromouracil (6.a) effectively forms base pairs with guanine nucleotides. This surprising observation has been explained by invoking a different tautomer of 6.a. Draw a different tautomer of 6.a and show how it can effectively base pair to a guanine nucleotide. (Tautomerization theory Topal, M. D., Fresco, J. R. Base Pairing and... 

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