2-Pyridinyl-N-(2,4-difluorobenzyl)aminoethyl Group As Thermocontrolled Implement for Protection of Carboxylic Acids.

A thermolabile protecting group strategy for carboxylic acids is expanded. Thermosensitive esters are readily prepared using a known procedure, and their stability under neutral condition is investigated. Effective thermolytic deprotection initiated only by temperature for different carboxylic acids is demonstrated, and the compatibility of a thermolytic protecting group with acidic and basic protecting groups in an orthogonal protection strategy is also presented. This study showed interesting correlations between the pKa of acids and the deprotection rate of their well-protected moieties.

Gel electrophoresis in a polyvinylalcohol coated fused silica capillary for purity assessment of modified and secondary-structured oligo- and polyribonucleotides.

Application of a polyvinylalcohol-coated (PVA-coated) capillary in capillary gel electrophoresis (CGE) enables the selective separation of oligoribonucleotides and their modifications at high resolution. Quality assessment of shorter oligomers of small interfering RNA (siRNA) is of key importance for ribonucleic acid (RNA) technology which is increasingly being applied in medical applications. CGE is a technique of choice for calculation of chemically synthesized RNAs and their modifications which are frequently obtained as a mixture including shorter oligoribonucleotides. The use of CGE with a PVA-coated capillary to analyze siRNA mixtures presents an alternative to conventionally employed techniques. Here, we present study on identification of the length and purity of RNA mixture ingredients by using PVA-coated capillaries. Also, we demonstrate the use of PVA-coated capillaries to identify and separate phosphorylated siRNAs and secondary structures (e.g. siRNA duplexes).

Boron Clusters as a Platform for New Materials: Synthesis of Functionalized o-Carborane (C2 B10 H12 ) Derivatives Incorporating DNA Fragments.

A synthetic strategy for functionalization of the three vertices of o-carborane and the attachment of the obtained triped to the solid support was developed. Further functionalization of the triped with short DNA sequences by automated DNA synthesis was achieved. The proposed methodology is a first example of boron cluster chemistry on a solid support opening new perspectives in boron cluster functionalization.