Current Organic Chemistry - Volume 19, Issue 11, 2015

Among the many emerging strategies for macromolecular self-assembly, only a few of them with strong and highly selective molecular recognition are able to achieve ordered self-organization in molecular level. DNA is unquestionably an ideal model in nature carrying such molecular recognition and has been used to design a variety of exquisite self-assemblies at nanoscales. In this review, we focus on the recent advances in DNA nanotechnology from the point of view of chemistry. Two major mechanisms for DNA selfassembly, tile-based DNA self-assembly and DNA origami, are introduced with some very intriguing examples and promising applications. On the other hand, DNA-inspired synthetic polymer is another appealing field for well-defined nanostructure fabrication. Therefore, the DNA-like behaviors of synthetic polymers are also reviewed, including the self-assembly of side-chain multiple-hydrogenbonding polymers and DNA (or its mimics) mediated polymerizations. The synthetic methods, self-organization mechanisms and potential applications of selected cases are illustrated. In the end, we highlight the challenges and drawbacks of the current methods for DNAand DNA-mimic-based supramolecular assembly with possible solutions.

Magnetic nanoparticles and especially superparamagnetic iron oxide nanoparticles (SPIONs) have found innumerable applications in bioscience and biotechnology. Accommodation of active molecules and forming homogeneous dispersion in solution, combined with easy capture by external magnetic fields has made them favorable candidates for molecular scale applications such as sensing and detection, imaging, targeted delivery, toxin decorporation, catalysis and pathogen removal. This review summarizes the recent advances and challenges in the above-mentioned applications.

Glass fiber reinforced plastics (GFRPs) are one of the most widely used composite materials and hold great potential applications due to their high-performance and cost effectiveness. Desired interfacial adhesion are paramount important in order to achieve enhanced affinity between fiber and resin matrix, and to improve the durability of GFRPs. One solution is fibers surface modification and functionization. Commercial glass fibers are sized by sizing solutions and are drawn into filaments. In the sizing solution, coupling agent works as “bridge” to bond fiber with polymers. There is an interphase between glass fiber and resin matrix, which is critical in determining the properties of fiber reinforced plastics. The commonly used coupling agent usually only affect thermosetting plastics, but have little effects the on thermoplastics, particularly when resins have few or no polar groups. For the fiber reinforced plastics composite, limitation is that while the strength is increased, the toughness of the materials degrades. In addition, the matrix polymers are limited due to available sizing solutions for fiber surface modification. Thus, methods such as treating glass fiber by coupling agents, grafting polymer chain onto fiber surface are alternative way to improve GFRPs performance. From the perspective of organic chemistry, this review focus specifically on introducing glasspolymer matrix interphase design, glass fiber sizing, methods to improve composites performance and problems associated with it. Insights and strategies were proposed and discussed as well.

Recently, DNA modifications, in vitro or in vivo, have attracted much attention because of the enhanced structural diversity and functionality of the modified DNA, and their broadened applications. In doing so, the availability of modified nucleosides/tides that can still be recognized by various enzymes required for the incorporation of nucleobases into DNA is critical. In this review, recent progress in developing such modified nucleosides/tides is summarized based on structural modification sites. Various modification strategies are compared and contrasted.

Reductive amination is considered as the most popular and established approaches which provide rapid access to different types of amines, important intermediates for the production of natural products and organic compounds, and also synthesis of essential precursors needed for drug development in chemical and biological systems. The current review discusses the progress of reductive amination catalysis from 2008 to the latest one. Also, efficacy of different reagents including organocatalysts, asymmetric and symmetric complexes of Ir, Rh, and Ru, boron, silicon reagents for enantio-, chemo-, and diastereoselective reactions is illustrated under various reaction conditions with a focus on the yield of the obtained products. Biocatalytic reductive amination for the synthesis of chiral amines and also utility of this reaction for the development of bioactive molecules are also briefly described.