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DNA-binding Metallo-intercalators
DNA-binding metallo-intercalators are positively charged, planar, polycyclic, aromatic compounds that unwind the DNA double helix and insert themselves between DNA base pairs. Metallo- intercalators insert themselves between two intact base pairs without expelling or replacing the original nitrogenous bases; the hydrogen bonds between the nitrogenous bases at the site of intercalation remain unbroken.Gill, Martin R., and Jim A. Thomas. "Ruthenium(ii) Polypyridyl Complexes and DNA-from Structural Probes to Cellular Imaging and Therapeutics - (RSC Publishing)." Chem Soc Rev, n.d. Web. 26 Jan. 2015. .Pages, Benjamin J., Dale L. Ang, Elise P. Wright, and Janice R. Aldrich-Wright. "Metal Complex Interactions with DNA." Royal Society of Chemistry, n.d. Web. 26 Jan. 2015. . In addition to π-stacking between the aromatic regions of the intercalator and the nitrogenous bases of DNA, intercalation is stabilized by van der Waals, hydrophobic, electrostatic, and entropic interactions. Thi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigonal Planar Molecular Geometry
In chemistry, trigonal planar is a molecular geometry model with one atom at the center and three atoms at the corners of an equilateral triangle, called peripheral atoms, all in one plane. In an ideal trigonal planar species, all three ligands are identical and all bond angles are 120°. Such species belong to the point group D3h. Molecules where the three ligands are not identical, such as H2CO, deviate from this idealized geometry. Examples of molecules with trigonal planar geometry include boron trifluoride (BF3), formaldehyde (H2CO), phosgene (COCl2), and sulfur trioxide (SO3). Some ions with trigonal planar geometry include nitrate (), carbonate (), and guanidinium (). In organic chemistry, planar, three-connected carbon centers that are trigonal planar are often described as having sp2 hybridization. Nitrogen inversion is the distortion of pyramidal amines through a transition state that is trigonal planar. Pyramidalization is a distortion of this molecular shape t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Van Der Waals Force
In molecular physics, the van der Waals force is a distance-dependent interaction between atoms or molecules. Unlike ionic or covalent bonds, these attractions do not result from a chemical electronic bond; they are comparatively weak and therefore more susceptible to disturbance. The van der Waals force quickly vanishes at longer distances between interacting molecules. Named after Dutch physicist Johannes Diderik van der Waals, the van der Waals force plays a fundamental role in fields as diverse as supramolecular chemistry, structural biology, polymer science, nanotechnology, surface science, and condensed matter physics. It also underlies many properties of organic compounds and molecular solids, including their solubility in polar and non-polar media. If no other force is present, the distance between atoms at which the force becomes repulsive rather than attractive as the atoms approach one another is called the van der Waals contact distance; this phenomenon resul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ruthenium
Ruthenium is a chemical element with the Symbol (chemistry), symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most other chemicals. Russian-born scientist of Baltic-German ancestry Karl Ernst Claus discovered the element in 1844 at Kazan State University and named ruthenium in honor of Russian Empire, Russia. Ruthenium is usually found as a minor component of platinum ores; the annual production has risen from about 19 tonnes in 2009Summary. Ruthenium platinum.matthey.com, p. 9 (2009) to some 35.5 tonnes in 2017. Most ruthenium produced is used in wear-resistant electrical contacts and thick-film resistors. A minor application for ruthenium is in platinu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ru(bpy)2(paip)2+
''Ru, ru, or RU may refer to: Russia * Russia (ISO 3166-1 alpha-2 country code) * Russian language (ISO 639 alpha-2 code) * .ru, the Internet country code top-level domain for Russia China * Rù (入), the entering tone in Chinese language phonetics * Rú (儒), a Chinese language term for Confucianism * Ru (surname) (茹), a Chinese surname * Ru River (汝), in Henan, China * Ru ware, a type of Chinese pottery Educational institutions * Radboud University Nijmegen, in Nijmegen, Netherlands * Radford University, in Virginia, USA * Rai University in Gujarat, India * Rajshahi University in Bangladesh * Rama University in India * Ramkhamhaeng University in Thailand * Regis University in Colorado, USA * Reykjavík University Iceland * Rhodes University in Grahamstown, South Africa * Rockefeller University in New York, USA * Rockhurst University in Missouri, USA * Roosevelt University in Chicago, Illinois, USA * Rowan University in New Jersey, USA * Ruse University in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entropic
Entropy is a scientific concept, as well as a measurable physical property, that is most commonly associated with a state of disorder, randomness, or uncertainty. The term and the concept are used in diverse fields, from classical thermodynamics, where it was first recognized, to the microscopic description of nature in statistical physics, and to the principles of information theory. It has found far-ranging applications in chemistry and physics, in biological systems and their relation to life, in cosmology, economics, sociology, weather science, climate change, and information systems including the transmission of information in telecommunication. The thermodynamic concept was referred to by Scottish scientist and engineer William Rankine in 1850 with the names ''thermodynamic function'' and ''heat-potential''. In 1865, German physicist Rudolf Clausius, one of the leading founders of the field of thermodynamics, defined it as the quotient of an infinitesimal amount of heat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrostatic
Electrostatics is a branch of physics that studies electric charges at rest (static electricity). Since classical times, it has been known that some materials, such as amber, attract lightweight particles after rubbing. The Greek word for amber, (), was thus the source of the word 'electricity'. Electrostatic phenomena arise from the forces that electric charges exert on each other. Such forces are described by Coulomb's law. Even though electrostatically induced forces seem to be rather weak, some electrostatic forces are relatively large. The force between an electron and a proton, which together make up a hydrogen atom, is about 36 orders of magnitude stronger than the gravitational force acting between them. There are many examples of electrostatic phenomena, from those as simple as the attraction of plastic wrap to one's hand after it is removed from a package, to the apparently spontaneous explosion of grain silos, the damage of electronic components during manufacturi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrophobic
In chemistry, hydrophobicity is the physical property of a molecule that is seemingly repelled from a mass of water (known as a hydrophobe). In contrast, hydrophiles are attracted to water. Hydrophobic molecules tend to be nonpolar and, thus, prefer other neutral molecules and nonpolar solvents. Because water molecules are polar, hydrophobes do not dissolve well among them. Hydrophobic molecules in water often cluster together, forming micelles. Water on hydrophobic surfaces will exhibit a high contact angle. Examples of hydrophobic molecules include the alkanes, oils, fats, and greasy substances in general. Hydrophobic materials are used for oil removal from water, the management of oil spills, and chemical separation processes to remove non-polar substances from polar compounds. Hydrophobic is often used interchangeably with lipophilic, "fat-loving". However, the two terms are not synonymous. While hydrophobic substances are usually lipophilic, there are exceptions, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stacking (chemistry)
In chemistry, pi stacking (also called π–π stacking) refers to the presumptive attractive, noncovalent pi interactions ( orbital overlap) between the pi bonds of aromatic rings. However this is a misleading description of the phenomena since direct stacking of aromatic rings (the "sandwich interaction") is electrostatically repulsive. What is more commonly observed (see figure to the right) is either a staggered stacking (parallel displaced) or pi-teeing (perpendicular T-shaped) interaction both of which are electrostatic attractive For example, the most commonly observed interactions between aromatic rings of amino acid residues in proteins is a staggered stacked followed by a perpendicular orientation. Sandwiched orientations are relatively rare. Pi stacking is repulsive as it places carbon atoms with partial negative charges from one ring on top of other partial negatively charged carbon atoms from the second ring and hydrogen atoms with partial positive charges on top of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polycyclic Compound
In the field of organic chemistry, a polycyclic compound is an organic compound featuring several closed rings of atoms, primarily carbon. These ring substructures include cycloalkanes, aromatics, and other ring types. They come in sizes of three atoms and upward, and in combinations of linkages that include tethering (such as in biaryls), fusing (edge-to-edge, such as in anthracene and steroids), links via a single atom (such as in spiro compounds), bridged compounds, and longifolene. Though poly- literally means "many", there is some latitude in determining how many rings are required to be considered polycyclic; many smaller rings are described by specific prefixes (e.g., bicyclic, tricyclic, tetracyclic, etc.), and so while it can refer to these, the title term is used with most specificity when these alternative names and prefixes are unavailable. In general, the term polycyclic includes polycyclic aromatic compounds, including polycyclic aromatic hydrocarbons, as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Bonds
In chemistry, a hydrogen bond (or H-bond) is a primarily electrostatic force of attraction between a hydrogen (H) atom which is covalently bound to a more electronegative "donor" atom or group (Dn), and another electronegative atom bearing a lone pair of electrons—the hydrogen bond acceptor (Ac). Such an interacting system is generally denoted , where the solid line denotes a polar covalent bond, and the dotted or dashed line indicates the hydrogen bond. The most frequent donor and acceptor atoms are the second-row elements nitrogen (N), oxygen (O), and fluorine (F). Hydrogen bonds can be intermolecular (occurring between separate molecules) or intramolecular (occurring among parts of the same molecule). The energy of a hydrogen bond depends on the geometry, the environment, and the nature of the specific donor and acceptor atoms and can vary between 1 and 40 kcal/mol. This makes them somewhat stronger than a van der Waals interaction, and weaker than fully covalent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogenous Bases
Nucleobases, also known as ''nitrogenous bases'' or often simply ''bases'', are nitrogen-containing biological compounds that form nucleosides, which, in turn, are components of nucleotides, with all of these monomers constituting the basic building blocks of nucleic acids. The ability of nucleobases to form base pairs and to stack one upon another leads directly to long-chain helical structures such as ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Five nucleobases—adenine (A), cytosine (C), guanine (G), thymine (T), and uracil (U)—are called ''primary'' or ''canonical''. They function as the fundamental units of the genetic code, with the bases A, G, C, and T being found in DNA while A, G, C, and U are found in RNA. Thymine and uracil are distinguished by merely the presence or absence of a methyl group on the fifth carbon (C5) of these heterocyclic six-membered rings. In addition, some viruses have aminoadenine (Z) instead of adenine. It differs in having an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
