Molecular Switches

Computer networks are a system of interconnected computers for the impetus of sharing the digital information among various networks. The concept of a networking began in 1962 when a server at the Massachusetts Institute of Technology (MIT) was connected to a server in Santa Monica, California for the purpose of communication between the two nodes. Since that time the proliferation of computers and computer networks has increased rapidly. One of the most significant challenges to networks is to prevent the attacks on their resources caused by inadequate network security which causes the malfunctioning of the system. The purpose of the project is establish a connection between the sectors of the networking domain. The project deals with the association of network in the enterprise and MNCs. Imagine a world with less interruption in the network functioning with the higher bandwidth usage. To support the better performance, resilience, security, maintainability and efficiency. Networking deals with the four layer of the OSI model. The purpose of the topology is to establish a seamless connection between the different routers and switches across the various geographical region.

Liquid crystals decorated gold nanoparticles are synthesized as the molecular architecture consists of the azobenzenes moieties with alkene as the peripheral units, which are connected to gold nanoparticles (Au-NPs) via thiolated phenolic units are in the middle. The morphology and mesomorphic properties were investigated by the field emission scanning electron microscope, high-resolution transmission electron microscopy, differential scanning calorimetry, and polarizing optical microscopy. The aromatic thiolated azobenzene moieties with gold nanoparticles showed smectic A phase with monotropic nature only appeared in the cooling cycle. HR-TEM measurement showed that the functionalized Au-NPs are well dispersed without any aggregation. However, the absorption spectrum of peripheral azobenzene units shows strong absorption maxima in the ultraviolet region at 378 nm due to π-π* transition. For n-π* transition, a weak absorption band is observed in the visible region at 472 nm. The photo-isomerization characteristic is measured using absorption spectroscopy. The photosatur-ation of Au-NPs is found at the time duration of 16 s. The thermal back relaxation is completed after the time interval of 70 min. Moreover, Au-NPs showed excellent stability towards photo-decay. Therefore, Au-NPs compound is suitable in the field of optical storage and molecular switching.

The enantiomer separation of a chiral Tröger's base analog and its use, as an optically active building block, in the construction of molecular superstructures are presented. Various strategies are illustrated here for the attachment of azo photoswitches to the Tröger's base scaffold without racemizing its stereogenic centers. The resulting optically active photoswitches introduced chirality, thermochromic, and phototunable properties to an achiral liquid crystal host. The doped mesophases reflected specific wavelengths of light owing to the formation of self-organized helical superstructures. These observations illustrate the potential use of the presented products as liquid crystal dopants.

The question how G-protein-coupled receptors transduce an extracellular signal by a sequence of transmembrane conformational transitions into an intracellular response remains to be solved at molecular detail. Herein, we use molecular dynamics simulations to reveal distinct conformational transitions of the adenosine A2A receptor, and we found that the conserved W246(6.48) residue in transmembrane helix TM6 performs a key rotamer toggle switch. Agonist binding induces the sidechain of W246(6.48) to fluctuate between two distinct conformations enabling the diffusion of water molecules from the bulk into the center of the receptor. After passing the W246(6.48) gate, the internal water molecules induce another conserved residue, Y288(7.53), to switch to a distinct rotamer conformation establishing a continuous transmembrane water pathway. Further, structural changes of TM6 and TM7 induce local structural changes of the adjacent lipid bilayer.

Concave Triphenylmethane DyestuffsTriply- and doubly-bridged as well as dye molecules (2, 18, and 11) connected by a single chain were prepared including the corresponding phenolphthalein and fluorescein derivatives (24a–c). The concave orange-coloured triphenylmethane dye 2 exhibits solvatochromic and halochromic effects different to nonmacrocyclic reference substances. The triphenylmethane dyes are reversibly transferred to the corresponding uncoloured macrocycles by changing the pH. The structures of 9, 22b, and 22c were confirmed by X-ray analyses.