73-39-2Relevant articles and documents
Structure and dynamics of disulfide cross-linked DNA triple helices
Osborne, Scott E.,Cain, Robert J.,Glick, Gary D.
, p. 1171 - 1182 (2007/10/03)
The design, synthesis, and characterization of two disulfide cross-linked intramolecular pyr·pur-pyr triple helices (IV and V) is presented. Placement of a covalent cross-link from the Hoogsteen strand to the Watson-Crick duplex produces two fundamental changes in the cross-linked DNAs relative to the parent sequence. First, formation of the cross-link results in an increase in the apparent pK(a) of the Hoogsteen cytosines by 1.5 pK(a) units (to 8.6 and 8.3 for IV and V, respectively) with a concomitant increase in thermal stability of ~40°C at pH 7.4. Second, the cross-link enforces the triplex structure over a wide range of solution conditions, including those that are physiologically relevant (e.g., pH 7.4, 155 mM Na+, 37°C). CD and NMR measurements indicate that the cross-link does not significantly perturb the geometry of IV and V relative to their unmodified counterpart. Because the disulfide crosslink effectively prevents conformational heterogeneity associated with pyr·pur-pyr triple helices containing C+·G-C base-triplets at neutral pH, constructs possessing this modification can serve as model systems to examine the structural and thermodynamic aspects of triplex formation in vitro and to aid in the development of sequences that bind with higher affinity and specificity.
PALLADIUM-CATALYZED CROSS-COUPLING REACTION OF ORGANOSTANNANES WITH NUCLEOSIDE HALIDES
Hassan, Mohamed Ezeldin
, p. 1944 - 1948 (2007/10/02)
A general reaction is described for the synthesis of C-5 substituted nucleosides through the coupling of organostannanes with nucleoside-palladium intermediate derived in situ from 5-iodouridine (or 5-iodo-2'-deoxyuridine) and .The reaction was used for the synthesis of C-5 aryl, heteroaryl, vinyl, allyl and alkyl substituted nucleosides.
A FACILE PHOTOCHEMICAL ROUTE TO C-5 AND C-6 ALLYL-SUBSTITUTED URACIL NUCLEOSIDES
Saito, Isao,Ikehira, Hideyuki,Matsuura, Teruo
, p. 1993 - 1994 (2007/10/02)
Irradiation of 5-iodouridine or 6-iodo-1,3-dimethyluracil in aq. acetonitrile in the presence of allyltrimethylsilane provided the corresponding 5- or 6-allylated product.
