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Heterocyclic compounds have an extremely important practical application, since many heterocycles are the basis of the most valuable medicinal substances, both natural (vitamins, enzymes, alkaloids, etc.) and synthetic biologically active compounds. The work mainly considers the most relevant directions for various purposes drugs search by modifying known bioactive natural, organoelement and framework compounds with 1,2-azole, oxazole, oxadiazole, thiazole, triazole, pyridine, pyrimidine heterocycles over the past 10 years. Chemical modification makes it possible to increase the water solubility of the compounds, which is important when choosing the pathways for the most rational drug introduction into the body, to reduce the toxicity of the corresponding substances, to increase the breadth of the therapeutic action, and also to give new valuable medicinal properties, thus significantly expanding their application in medicine and agriculture.

Hyaluronan (HA), a non-branched and multifunctional glycosaminoglycan, attracted interest by its breadth of biological roles, despite its structural simplicity. HA was considered a versatile building block to develop new biomaterials for more and more diverse and ingenious biomedical applications, such as scaffolds for tissue engineering, including cell and bioactive molecules, regenerative medicine, coatings and carriers used in imagistic investigations or therapy. The challenge of selective chemical reactions comes from HA limited solubility in organic solvents and sensitivity to enzymatic, mechanic and thermal degradation. All functional groups of HA can be modified by conjugation or covalent crosslinking with synthetic or natural compounds. All these modifications intent to improve the mechanical, rheological, swelling and controlled degradation properties of native HA in related biomaterials.

[EN] The main goal of the present work was to investigate the damages photoinduced by pterin (Ptr), an endogenous photosensitizer present in human skin under pathological conditions, on a globular protein such as ubiquitin (Ub). Particular attention has been paid on the formation of covalent adducts between Ptr and the protein that can behave as photoantigen and provoke an immune system response. Here, a multifaceted approach including UV-visible spectrophotometry, fluorescence spectroscopy, electrophoresis, size exclusion chromatography, and mass spectrometry is used to establish the Ub changes triggered by UV-A irradiation in the presence of Ptr. Under anaerobic conditions, the only reaction corresponds to the formation of a covalently bound Ptr-Ub adduct that retains the spectroscopic properties of the free photosensitizer. A more complex scheme is observed in air-equilibrated solutions with the occurrence of three different processes, that is, formation of a Ptr-Ub adduct, dimerization, and fragmentation of the protein. ; The present work was partially supported by Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET-Grants PIP 112-200901-0304 and PIP 11220120100072CO), Agencia de Promocion Cientifica y Tecnologica (ANPCyT-Grants PICT-2015-1988 and PICT 2016-00130), Universidad Nacional de La Plata (UNLP-Grant X712 and X840), and Universidad de Buenos Aires (UBA-Grant 000110BA). Funding from the Programa CSIC de Cooperacion Cientifica para el Desarrollo (iCOOPLight project ref 20105CD0017) and Spanish government (PGC2018-096684-B-I00) is gratefully acknowledged. The Ultraflex II (Bruker) TOF/TOF mass spectrometer was supported by a grant from ANPCYT, PME2003 No. 125, and the ESI-MS Q Exactive, Thermo Scientific, by a grant from ANPCYT, PME2011-PPL2-0009, CEQUIBIEM, DQB, FCEN, UBA. The proteomic analysis was performed in the proteomics facility of SCSIE University of Valencia. This proteomics laboratory is a member of Proteored, PRB3 and is supported by grant PT17/0019, of the PE I+D+i ...

Nowadays, consumers are increasingly aware of the relationship between diet and health, showing a greater preference of products from natural origin. In the last decade, seaweeds have outlined as one of the natural sources with more potential to obtain bioactive carbohydrates. Numerous seaweed polysaccharides have aroused the interest of the scientific community, due to their biological activities and their high potential on biomedical, functional food and technological applications. To obtain polysaccharides from seaweeds, it is necessary to find methodologies that improve both yield and quality and that they are profitable. Nowadays, environmentally friendly extraction technologies are a viable alternative to conventional methods for obtaining these products, providing several advantages like reduced number of solvents, energy and time. On the other hand, chemical modification of their structure is a useful approach to improve their solubility and biological properties, and thus enhance the extent of their potential applications since some uses of polysaccharides are still limited. The present review aimed to compile current information about the most relevant seaweed polysaccharides, available extraction and modification methods, as well as a summary of their biological activities, to evaluate knowledge gaps and future trends for the industrial applications of these compounds. Key teaching points: Structure and biological functions of main seaweed polysaccharides. Emerging extraction methods for sulfate polysaccharides. Chemical modification of seaweeds polysaccharides. Potential industrial applications of seaweed polysaccharides. Biological activities, knowledge gaps and future trends of seaweed polysaccharides. ; The research leading to these results was supported by MICINN supporting the Ramón y Cajal grant for M.A. Prieto (RYC-2017-22891); by Xunta de Galicia for supporting the program EXCELENCIA-ED431F 2020/12, the post-doctoral grant of M. Fraga-Corral (ED481B-2019/096), the pre-doctoral grant of P. Garcia-Oliveira (ED481A-2019/295) the program Grupos de Referencia Competitiva (GRUPO AA1-GRC 2018) that supports the work of J. Echave; by University of Vigo for supporting the predoctoral grant of M. Carpena (Uvigo-00VI 131H 6410211) and Becas de Fundación ONCE Programme "Oportunidad al Talento" to support the work of A. Soria-Lopez. Authors are grateful to Ibero-American Program on Science and Technology (CYTED— AQUA-CIBUS, P317RT0003), to the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019) that supports the work of P. Otero. The JU receives support from the European Union's Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The project SYSTEMIC Knowledge hub on Nutrition and Food Security, has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS and FACCE-JPI launched in 2019 under the ERA-NET ERA-HDHL (n° 696295). ; info:eu-repo/semantics/publishedVersion

Aptamers are promising molecules for a wide range of applications in biomedicine and various diagnostic systems due to their unique properties as selective ligands, speci cally obtained for a selected target using methods of arti cial evolution and combinatorial chemistry. We discuss strategies of obtaining aptamers in vitro and using their chemical modi cations, as well as approaches to design initial compound libraries based on in silico prestructuring. Limitations are formulated, and a direction for the development of the eld in obtaining new aptamers is proposed.

International audience ; AbstractKey messageIncreasing environmental pressures appearing over the last few years have led to important changes in the field of wood protection. In this context, new technologies, based either on thermal or chemical modifications, suggest increasing interest in prospect of programmed ban of biocide products.• ContextThe evolution of the regulations on the use of biocide products has led to important changes in the field of wood preservation, leading to an increasing interest for non-biocide treatments like thermal or chemical modifications to face to the programmed ban of biocide products.• AimsThe paper reviews the different non-biocide alternatives developed currently on an industrial scale, highlighting their main characteristics and applications.• ResultsDifferent treatments have been developed on an industrial scale involving mainly thermal modifications and acetylation, furfurylation and DMDHEU constituting already available solutions.• ConclusionDifferent non-biocide alternatives already exist and will become more important in the next decades due to the increasing legislative pressure driven by environmental considerations.

International audience ; AbstractKey messageIncreasing environmental pressures appearing over the last few years have led to important changes in the field of wood protection. In this context, new technologies, based either on thermal or chemical modifications, suggest increasing interest in prospect of programmed ban of biocide products.• ContextThe evolution of the regulations on the use of biocide products has led to important changes in the field of wood preservation, leading to an increasing interest for non-biocide treatments like thermal or chemical modifications to face to the programmed ban of biocide products.• AimsThe paper reviews the different non-biocide alternatives developed currently on an industrial scale, highlighting their main characteristics and applications.• ResultsDifferent treatments have been developed on an industrial scale involving mainly thermal modifications and acetylation, furfurylation and DMDHEU constituting already available solutions.• ConclusionDifferent non-biocide alternatives already exist and will become more important in the next decades due to the increasing legislative pressure driven by environmental considerations.

Key message Increasing environmental pressures appearing over the last few years have led to important changes in the field of wood protection. In this context, new technologies, based either on thermal or chemical modifications, suggest increasing interest in prospect of programmed ban of biocide products. The evolution of the regulations on the use of biocide products has led to important changes in the field of wood preservation, leading to an increasing interest for non-biocide treatments like thermal or chemical modifications to face to the programmed ban of biocide products. The paper reviews the different non-biocide alternatives developed currently on an industrial scale, highlighting their main characteristics and applications. Different treatments have been developed on an industrial scale involving mainly thermal modifications and acetylation, furfurylation and DMDHEU constituting already available solutions. Different non-biocide alternatives already exist and will become more important in the next decades due to the increasing legislative pressure driven by environmental considerations.