Recent Advances on Metal-Free, Visible-Light- Induced Catalysis for Assembling Nitrogen- and Oxygen-Based Heterocyclic Scaffolds

Heterocycles are important class of structures, which occupy a major space in the domain of natural and bioactive compounds. For this reason, development of new synthetic strategies for their controllable synthesis became of special interests. The development of novel photoredox systems with wide-range application in organic synthesis is particularly interesting. Organic dyes have been widely applied as photoredox catalysts in organic synthesis. Their low costs compared to the typical photocatalysts based on transition metals make them an excellent alternative. This review describes proceedings since 2015 in the area of application of metal-free, visible-light-mediated catalysis for assembling various heterocyclic scaffolds containing five- and six-membered rings bearing nitrogen and oxygen heteroatoms

Nouvelles aryl-alkyl-piperazines comportant des acides amines N-acyles, ligands de récepteurs sérotoninergiques

Ce travail présente des nouveaux composés ciblant les récepteurs sérotoninergiques. La première partie traite de la synthèse supposée d'une chimiothèque d'arylpiperazines. Plusieurs composés montrent une haute affinité pour 5-HT1A(K1=3-52nM) . Des tests pharmacologiques pré-cliniques ont révélé des comportements de type agoniste complet ou partiel de 5-HT1A ou antagoniste 5-HT1A/5-HT2A. La synthèse supportée de 64 dérivés sulfonamide de la proline carboxamide est décrite, visant l'obtention d'antagonistes de 5-HT7. La dernière partie traite de la synthèse supportée sur lanternes BAL de dérivés d'arylalkyl amines ciblant les récepteurs des amines biogéniques du SNC. Une synthèse originale supportée d'une nouvelle classe d'arylpipérazines a été présentée. L'étude biologique in vitro a révélé plusieurs doubles ligands 5-TH1A/5-HT2A possédant in vivi une activité anxiolytique et antidépressive. Les résultats du criblage des composés sur 5-HT7 aideront à la conception de nouvelles séries.MONTPELLIER-BU Pharmacie (341722105) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

Harvesting Entropy for Random Number Generation for Internet of Things Constrained Devices Using On-Board Sensors

Entropy in computer security is associated with the unpredictability of a source of randomness. The random source with high entropy tends to achieve a uniform distribution of random values. Random number generators are one of the most important building blocks of cryptosystems. In constrained devices of the Internet of Things ecosystem, high entropy random number generators are hard to achieve due to hardware limitations. For the purpose of the random number generation in constrained devices, this work proposes a solution based on the least-significant bits concatenation entropy harvesting method. As a potential source of entropy, on-board integrated sensors (i.e., temperature, humidity and two different light sensors) have been analyzed. Additionally, the costs (i.e., time and memory consumption) of the presented approach have been measured. The results obtained from the proposed method with statistical fine tuning achieved a Shannon entropy of around 7.9 bits per byte of data for temperature and humidity sensors. The results showed that sensor-based random number generators are a valuable source of entropy with very small RAM and Flash memory requirements for constrained devices of the Internet of Things

EAP for IoT ::more efficient transport of authentication data - TEPANOM case study

Internet of Things security has been the most challenging part of the domain. Combining strong cryptography, lifelong security with highly constrained devices under conditions of limited energy consumption and no maintenance time makes it extremely difficult task. In this paper it has been presented approach that combines authentication and bootstrapping protocol (TEPANOM) with authentication framework optimized for the IEEE 802.15.4 networks (EAP with SEAPOL adaptation layer) to achieve significant network resource usage reduction. The EAP-TEPANOM solution has achieved substantial 42% reduction in the number of transferred packets and 35% reduction of the transferred data. This results have placed as one of the most lightweight EAP methods that has been tested in this research

Extending Extensible Authentication Protocol over IEEE 802.15.4 Networks

Internet into our physical world and making it present everywhere. This evolution is also raising challenges in issues such as privacy, and security. For that reason, this work is focused on the integration and lightweight adaptation of existing authentication protocols, which are able also to offer authorization and access control functionalities. In particular, this work is focused on the Extensible Authentication Protocol (EAP). EAP is widely used protocol for access control in local area networks such Wireless (802.11) and wired (802.3). This work presents an integration of the EAP frame into IEEE 802.15.4 frames, demonstrating that EAP protocol and some of its mechanisms are feasible to be applied in constrained devices, such as the devices that are populating the IoT networks