Chitosan is a marine-origin polysaccharide obtained from the deacetylation of chitin, the main component of crustaceans’ exoskeleton, and the second most abundant in nature. Although this biopolymer has received limited attention for several decades right after its discovery, since the new millennium chitosan has emerged owing to its physicochemical, structural and biological properties, multifunctionalities and applications in several sectors. This review aims at providing an overview of chitosan properties, chemical functionalization, and the innovative biomaterials obtained thereof. Firstly, the chemical functionalization of chitosan backbone in the amino and hydroxyl groups will be addressed. Then, the review will focus on the bottom-up strategies to process a wide array of chitosan-based biomaterials. In particular, the preparation of chitosan-based hydrogels, organic–inorganic hybrids, layer-by-layer assemblies, (bio)inks and their use in the biomedical field will be covered aiming to elucidate and inspire the community to keep on exploring the unique features and properties imparted by chitosan to develop advanced biomedical devices. Given the wide body of literature that has appeared in past years, this review is far from being exhaustive. Selected works in the last 10 years will be considered.

Compounds that bind in the minor groove of DNA have found use in the experimental treatment of cancer and certain infectious diseases. Furthermore, agents which target and can recognize discrete sequences of DNA have the potential to offer selective therapies by modulating the activity of specific transcription factors or genes. For this reason, a number of sequence-selective DNA binding agents have been evaluated with a range of affinities and recognition fidelities. In this respect, the pyrrolo[2,1-c][1,4]benzodiazepines (PBDs) are of interest as they bind to guanine residues in the minor groove with a preference for Pu-G-Pu sequences. A dramatic increase in cytotoxicity and sequence selectivity has been achieved by linking two PBD units to form PBD dimers as cross-linking agents on opposite DNA strands (e.g., interstrand cross-links). SJG-136 is currently undergoing Phase I evaluation in both the United States (through the NCI) and United Kingdom (through Cancer Research United Kingdom). This review will focus on design, synthesis and structure activity relationship studies of pyrrolobenzodiazepines as anticancer therapeutics reported since 2003.

Functionalisation of polymers using organosilanes via nucleophilic attack of the epoxide rings is successful under mild pH when the polymers contain carboxylic groups.

Recent iminosugar syntheses starting both from commercially available sugars and non-glycidic precursors, are reported in this article. Exploiting carbohydrate starting materials, different synthetic approaches are described, mainly based on the introduction of an amino function in the sugar skeleton and the subsequent aminocyclization in order to generate the piperidine or pyrrolidine ring. The aminocyclization has been performed in different ways: reductive amination of azidoketones, intramolecular amino group attack on leaving groups and activated double bonds. In some cases one-pot amination and cyclization have been performed using ammonia or a primary amine and a di-functionalised sugar. Bicyclic compounds have also been obtained through these procedures. Starting from non-carbohydrate precursors, the nitrogen containing cycle, already present or easily obtained by Diels-Alder reactions, has been variously functionalised and stereo-differentiated by asymmetric induction or by resolution of the racemate. The syntheses of a variety of innovative structures, such as 1-N-iminosugars, iminosugars with two nitrogen atoms in the ring, iminosugars incorporating a guanidine function, imidazole-, triazole- and tetrazolefused iminosugars, sugar-like aza-, oxa-, and thio-indolizidines, are reported. Finally the synthesis of glycoconjugate-related iminosugars, where the “pseudoanomeric” centre is linked to amino acid or peptide residues, and iminosugar phosphonates and nucleosides have been reviewed.

Covering: 2000 to 2010 Kdo belongs to the 3-deoxysugar ‘family’ and is a critical monosaccharidic component of lipopolysaccharides (LPSs) in Gram-negative bacteria. The incorporation of Kdo into LPSs is a vital step in the assembly of the protective outer membrane of Gram-negative bacteria. This review intends to present recent advances on structural/biocatalytic knowledge on the four enzymes involved in Kdo metabolism, and on the synthesis and biological activity of analogues of biosynthetic intermediates, highlighting the potential of this pathway for the discovery of new antibacterials – a pressing need due to the emergence of new classes of antibiotic-resistant bacteria.