Base analog

Fujita et al. were the first to develop a calculation method that was based, analogously to the Hammett approach, on substituent constants r[6] (see Eq. (7))... 

It has been found that 6-aminopyrazinone (Scheme 2), when incorporated as a pyrimidine base analog into an ohgonucleotide, might participate in a nonstandard base pair that retains Watson-Crick geometry [14],... 

Transition metals have been used to trap and stabilize many different types of reactive intermediates, such as carbenes. Reactive silicon intermediates have only recently yielded to this approach. In the case of alkenes, for instance, transition metal complexes are generally made by exposing the alkene to a transition metal bearing suitable leaving groups (e.g., carbonyl). Unlike carbon-based intermediates, however, silicon-based analogs have been very difficult to prepare until recently. Unless... 

Three fluorescent purine analogs will be described here 2-aminopurine (2AP) [183] and 8-vinyladenine (8VAD), both of which mimic adenine, and N1,N6-ethenoadenine (e-AD). Their structures are shown in Figure 11-15. 2AP is probably the most widely used fluorescent DNA base analog, being utilized as a probe for DNA conformational dynamics [184, 185], due to the environmental specificity of... 

Fig. 6 Dynamic molecular motions can gate DNA-mediated charge transport. Two time constants (5 and 75 ps) are observed for hole transfer from photoexcited ethidium, tethered and intercalated near the end of a 14-base pair DNA duplex, to a base analog, 7-deazaguanine, in DNA. The 5 ps time constant, which is independent of distance between 10-17 A, is due to direct hole transfer, while the 75 ps time constant corresponds to reorientation of the ethidium before hole transfer. Adapted from [96]... 

The ability of the ubiquitous Co(salen) complex and its tetradentate Schiff base analog complexes to bind 02 reversibly has been central to most investigations of its coordination chemistry. A density functional computational investigation has been carried out on the 02 carriers... 

Wade and Williams have reported the synthesis of a carborane-based analog of polyi/t-phenylene).122 The rodlike polymer (91) (Fig. 55) was prepared by the catalytic... 

Figure 55 The rodlike polymer (91) that is the carhorane-based analog of poly(/ -phenylene ). (Adapted from ref. 123.)...

Pyrimidine- and pyridazine-based analogs have recently emerged as PHD inhibitors and IC50 values in the range of 2-175 nM have been reported in a FRET-based PHD2 assay [52], A number of different substitutions ranging from alkyl, aryl, heteroaryl, and amino groups are accommodated in this series of compounds. While 1-pyrrolidinyl-, 23 and 1-piperidinyl-, 24,... 

Figure 5. Substituted pyrimidine base analogs evaluated in FEP calculations...

H Gausepohl, U Pieles, RW Frank. Schiff base analog formation during in situ activation by HBTU and TBTU, in JA Smith, JR Rivier, eds. Peptides Chemistry and Biology. Proceedings of the 12th American Peptide Symposium, Escom, Leiden, 1992, pp 523-524. 

Generally, DNMT inhibitors can be divided in two big dasses. One group consists of base analogs which are incorporated into DNA and act as suidde substrates for DNMT via a covalent adduct formation. The other group acts on the free enzyme in the same way as classic enzyme inhibitors do. 

Poirier LA, Stoner GD, Shimkin MB Bioassay of alkyl halides and nucleotide base analogs by pulmonary tumor response in Strain A mice. Cancer Res 35(6) 1411-1415, 1975... 

In a later work, the iron(III) complex stability and structure of 75 was compared to other NTA-based analogs 76, 77, 78 and 79 °. Complex stability was in the order 75 > 79 > 76 > 77 = 78. CD spectra revealed that the enantiomeric pair 77 and 78 gave A-and A-configurations, respectively, by reference to the assignment for ferrichrome Both 75 and its diastereomer 76 showed preference for the A-cis configuration. 

Equation (50) (or its CCSD/EOMCCSD-based analog, Eq. (53)) defines the exact MMCC formalism for ground and excited states. This equation allows us to improve the CC/EOMCC (e.g. CCSD/EOMCCSD) results, in a state-selective manner, by adding the noniterative corrections (in practice, one of the approximate forms of or obtained using the... 

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