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Pyranoid spirofused sugar derivatives represent a class of compounds with a significant impact in the literature. Under the structural point of view, the rigidity inferred by the spirofused entity has made these compound object of interest mainly as enzymatic inhibitors, in particular of carbohydrate processing enzymes among which glycogen phosphorylase and sodium glucose co-transporter 2, important target enzymes for diverse pathological states. Most of the developed compounds present the spirofused entity at the C1 position of the sugar moiety, nevertheless spirofused entities can also be found at other sugar ring positions. The main spirofused entities encountered are spiroacetals/thioacetals, spiro-hydantoin and derivatives, spiro-isoxazolines, spiro-aminals, spiro-lactams, spiro-oxathiazole and spiro-oxazinanone, but also other are present.

The paper investigates the use of poly(1-vinylpyrrolidone-co-2-dimethylaminoethylmetacrilate) (PVP-co-DMAEMA) as a novel coating agent in the preparation of alginate-based microcapsule for the supplement delivery of probiotics. Probiotic Lactobacillus plantarum is used to study the viability of the encapsulated bacterium when exposed to conditions simulating the gastrointestinal tract and industrial process. Results demonstrate that the PVP-co-DMAEMA polymer constitutes a pH-responsive coating suitable for probiotic supplement delivery.

The use of cellulose nanocrystals (CNCs) as a biomaterial able to inhibit host cell bacterial adhesion is described. Pre-incubation of E. coli ATCC 25922 with a suspension of 0.1% CNCs afforded a significant 2log reduction of bacterial adhesion to the intestinal cell monolayer HT29. This effect could be attributed to the interaction between the CNCs and the bacterial cell surface as confirmed using fluorescence microscopy experiments.

Probiotic ingestion is recommended as a preventive approach to maintain the balance of the intestinal microbiota and to enhance the human well-being. During the whole life of each individual, the gut microbiota composition could be altered by lifestyle, diet, antibiotic therapies and other stress conditions, which may lead to acute and chronic disorders. Hence, probiotics can be administered for the prevention or treatment of some disorders, including lactose malabsorption, acute diarrhoea, irritable bowel syndrome, necrotizing enterocolitis and mild forms of inflammatory bowel disease. The probiotic-mediated effect is an important issue that needs to be addressed in relation to strain-specific probiotic properties. In this work, the probiotic properties of new Lactobacillus and Bifidobacterium strains were screened, and their effects in vitro were evaluated. They were screened for probiotic properties by determining their tolerance to low pH and to bile salts, antibiotic sensitivity, antimicrobial activity and vitamin B8, B9 and B12 production, and by considering their ability to increase the antioxidant potential and to modulate the inflammatory status of systemic-miming cell lines in vitro. Three out of the examined strains presenting the most performant probiotic properties, as Lactobacillus plantarum PBS067, Lactobacillus rhamnosus PBS070 and Bifidobacterium animalis subsp. lactis PBSO75, were evaluated for their effects also on human intestinal HT-29 cell line. The obtained results support the possibility to move to another level of study, that is, the oral administration of these probiotical strains to patients with acute and chronic gut disorders, by in vivo experiments.

C-Glucoside derivatives covalently linked to the arsenic atom in different oxidation states have been synthesized by avoiding protection-deprotection steps. While compound 1, bearing an AsV atom, did not show any significant biological activity, compound 2, in which the glucose moiety is linked to the arsenic atom as dithioarsenical (AsIII), showed promising antiproliferative activity on a cell line of neuroblastoma (SK-N-BE). C-Glucoside derivatives covalently linked to the arsenic atom in different oxidation states have been synthesized. The C-glucoside conjugated to the phenyldithioarsolan group, showed promising antiproliferative activity on human neuroblastoma cells (SK-N-BE).

Calixarene-iminosugar derivatives bearing four 1-deoxynojirimycin units at the upper or lower rim of calix[4]arenes in a fixed cone conformation were synthesized by copper-catalyzed azide-alkyne cycloaddition (CuAAC) and their inhibitory activity was evaluated against five glycosidases. Modest but significant affinity enhancements of up to seven per 1-deoxynojirimycin unit over the monovalent iminosugar derivative were observed for the inhibition of Jack bean (Canavalia ensiformis) a-mannosidase. It was also demonstrated that the residual copper ions did not contribute to the inhibitory properties of the newly prepared calixarene-based multivalent iminosugars.

Nanoliposomes decorated on their surface with ligands for Ab-peptides, the key morphological features of Alzheimer's disease (AD), have been synthesized and characterized for their ability to target Abpeptide aggregates. A tricyclic benzopyrane-glycofused structure has been exploited as Ab-peptide ligand, which was linked to liposomes via a copper-free, chemoselective, biocompatible click chemistry reaction. The tricyclic-decorated liposomes presented a mean diameter in the nanomolar range (150 e200 nm), a negative z-potential and a good stability, at least up to one month. Integrity studies performed in the presence of serum proteins indicated that these decorated nanoliposomes fulfill the requirements for in vivo applications. NMR experiments carried out with Ab1-42 oligomers using both surface functionalized and plain (control) liposomes, revealed that the binding ability of the nanoliposomes was mediated by the presence of the tricyclic ligand on their surface. Finally ThT assay carried out with tricyclic-decorated liposomes showed significant decrease in thioflavine T fluorescence after 24 h, suggesting a significant inhibition/delay of Ab1-42 aggregation

The research project is focused on the development and the synthesis of glycoderivatives as potential drug candidates, for therapeutic use, and as molecular tools, for the study of biological processes. The project includes the study of SGLT1 (Sodium-Glucose co-transporter 1), its role in inflammatory processes and the development of potential carbohydrate-based anti-inflammatory agents. Furthermore, new glycoderivatives and glycoconjugates will be synthetized for other potential pharmacological applications such as the targeting of cytotoxic drugs, as novel potential anticancer agents, and for the development of molecular tools to study several biological phenomena.

A set of heterobifunctional oligo ethylene glycols have been synthesized in a straightforward and stepwise manner starting from inexpensive, commercially available, tetraethylene glycol. Introduction of terminal allyl moieties followed by reductive ozonolysis allowed controlled elongation. Mono-allyl derivatives were used for the elongation with a functionalized moiety and for successive introduction of different functional groups on the chain terminal

A new versatile thiophene derivative exomethylene-3,4- ethylenedioxythiophene (emEDOT) is introduced. The molecule can be straightforwardly prepared in two steps from commercially available derivatives and enables facile further derivatization through both acid catalyzed additions of alcohols and standard thiol-ene click chemistry. The preparation of electrochromic materials and of an electrochemical avidine sensor is shown by the oxidative polymerizations of several functionalized EDOT monomers straightforwardly prepared from emEDOT

Cancer is one of the major causes of death worldwide. As a consequence, many different therapeutic approaches, including the use of glycosides as anticancer agents, have been developed. Various glycosylated natural products exhibit high activity against a variety of microbes and human tumors. In this review we classify glycosides according to the nature of their aglycone (non-saccharidic) part. Among them, we describe anthracyclines, aureolic acids, enediyne antibiotics, macrolide and glycopeptides presenting different strengths and mechanisms of action against human cancers. In some cases, the glycosidic residue is crucial for their activity, such as in anthracycline, aureolic acid and enediyne antibiotics; in other cases, Nature has exploited glycosylation to improve solubility or pharmacokinetic properties, as in the glycopeptides. In this review we focus our attention on natural glycoconjugates with anticancer properties. The structure of several of the carbohydrate moieties found in these conjugates and their role are described. The structure-activity relationship of some of these compounds, together with the structural features of their interaction with the biological targets, are also reported. Taken together, all this information is useful for the design of new potential anti-tumor drugs. © The Royal Society of Chemistry 2011.