Related Research Articles
Supramolecular chemistry refers to the branch of chemistry concerning chemical systems composed of a discrete number of molecules. The strength of the forces responsible for spatial organization of the system range from weak intermolecular forces, electrostatic charge, or hydrogen bonding to strong covalent bonding, provided that the electronic coupling strength remains small relative to the energy parameters of the component. While traditional chemistry concentrates on the covalent bond, supramolecular chemistry examines the weaker and reversible non-covalent interactions between molecules. These forces include hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, pi–pi interactions and electrostatic effects.
In organic chemistry, crown ethers are cyclic chemical compounds that consist of a ring containing several ether groups (R−O−R’). The most common crown ethers are cyclic oligomers of ethylene oxide, the repeating unit being ethyleneoxy, i.e., −CH2CH2O−. Important members of this series are the tetramer (n = 4), the pentamer (n = 5), and the hexamer (n = 6). The term "crown" refers to the resemblance between the structure of a crown ether bound to a cation, and a crown sitting on a person's head. The first number in a crown ether's name refers to the number of atoms in the cycle, and the second number refers to the number of those atoms that are oxygen. Crown ethers are much broader than the oligomers of ethylene oxide; an important group are derived from catechol.
In chemistry, a molecule or ion is called chiral if it cannot be superposed on its mirror image by any combination of rotations, translations, and some conformational changes. This geometric property is called chirality. The terms are derived from Ancient Greek χείρ (cheir) 'hand'; which is the canonical example of an object with this property.
In chemistry, the valence or valency of an element is the measure of its combining capacity with other atoms when it forms chemical compounds or molecules. Different authors use different definitions of valence, creating a debate about which definition is correct. For example, some authors confuse coordination number with valence or oxidation state with valence, despite the fact those three terms are three different things.
Hexamethylphosphoramide, often abbreviated HMPA, is a phosphoramide (an amide of phosphoric acid) with the formula [(CH3)2N]3PO. This colorless liquid is a useful reagent in organic synthesis.
Heptalene is a polycyclic hydrocarbon with chemical formula C12H10, composed of two fused cycloheptatriene rings. It is an unstable, non-planar compound which is non-aromatic. The dianion, however, satisfies Hückel's rule, is thermally stable, and is planar.
An inorganic nonaqueous solvent is a solvent other than water, that is not an organic compound. These solvents are used in chemical research and industry for reactions that cannot occur in aqueous solutions or require a special environment. Inorganic nonaqueous solvents can be classified into two groups, protic solvents and aprotic solvents. Early studies on inorganic nonaqueous solvents evaluated ammonia, hydrogen fluoride, sulfuric acid, as well as more specialized solvents, hydrazine, and selenium oxychloride.
Jack David Dunitz FRS was a British chemist and widely known chemical crystallographer. He was Professor of Chemical Crystallography at the ETH Zurich from 1957 until his official retirement in 1990. He held Visiting Professorships in the United States, Israel, Japan, Canada, Spain and the United Kingdom.
Etonitazene, also known as EA-4941 or CS-4640, is a benzimidazole opioid, first reported in 1957, that has been shown to have approximately 1,000 to 1,500 times the potency of morphine in animals.
In chemistry, a Grob fragmentation is an elimination reaction that breaks a neutral aliphatic chain into three fragments: a positive ion spanning atoms 1 and 2, an unsaturated neutral fragment spanning positions 3 and 4, and a negative ion comprising the rest of the chain.
In medicinal chemistry, bioisosteres are chemical substituents or groups with similar physical or chemical properties which produce broadly similar biological properties in the same chemical compound. In drug design, the purpose of exchanging one bioisostere for another is to enhance the desired biological or physical properties of a compound without making significant changes in chemical structure. The main use of this term and its techniques are related to pharmaceutical sciences. Bioisosterism is used to reduce toxicity, change bioavailability, or modify the activity of the lead compound, and may alter the metabolism of the lead.
Rolf Huisgen was a German chemist. His importance in synthetic organic chemistry extends to the enormous influence he had in post-war chemistry departments in Germany and Austria, due to a large number of his habilitants becoming professors. His major achievement was the development of the 1,3-dipolar cycloaddition reaction, also called the Huisgen cycloaddition.
Albert Jakob Eschenmoser (born 5 August 1925) is a Swiss organic chemist, best known for his work on the synthesis of complex heterocyclic natural compounds, most notably vitamin B12. In addition to his significant contributions to the field of organic synthesis, Eschenmoser pioneered work in the Origins of Life (OoL) field with work on the synthetic pathways of artificial nucleic acids. Before retiring in 2009, Eschenmoser held tenured teaching positions at the ETH Zurich and The Skaggs Institute for Chemical Biology at The Scripps Research Institute in La Jolla, California as well as visiting professorships at the University of Chicago, Cambridge University, and Harvard.
Mercury(II) hydroxide or mercuric hydroxide is the metal hydroxide with the chemical formula Hg(OH)2. The compound has not been isolated in pure form, although it has been the subject of several studies. Attempts to isolate Hg(OH)2 yield yellow solid HgO.
Lanostane or 4,4,14α-trimethylcholestane is a tetracyclic chemical compound with formula C
30H
54. It is a polycyclic hydrocarbon, specifically a triterpene. It is an isomer of cucurbitane.
1,2,3,4,5-Cyclopentanepentol, also named cyclopentane-1,2,3,4,5-pentol or 1,2,3,4,5-pentahydroxycyclopentane is a chemical compound with formula C
5H
10O
5 or (–CHOH–)
5, whose molecule consists of a ring of five carbon atoms, each connected to one hydrogen and one hydroxyl group. The unqualified term "cyclopentanepentol" usually refers to this compound. There are four distinct stereoisomers with this same structure.
1,2,3,4-Cyclohexanetetrol (also named cyclohexane-1,2,3,4-tetrol, 1,2,3,4-tetrahydroxycyclohexane, or ortho-cyclohexanetetrol) is an organic compound whose molecule can be described as a cyclohexane with four hydroxyl (OH) groups substituted for hydrogen atoms on four consecutive carbon atoms. Its formula can be written C
6H
12O
4, C
6H
8(OH)
4, or (–CH(OH)–)4(–CH
2–)2.
1,2,4,5-Cyclohexanetetrol (also named cyclohexane-1,2,4,5-tetrol, 1,2,4,5-tetrahydroxycyclohexane, or para-cyclohexanetetrol) is an organic compound whose molecule can be described as a cyclohexane with four hydroxyl (OH) groups substituted for hydrogen atoms on two non-adjacent pairs of adjacent carbon atoms. Its formula can be written C
6H
12O
4, C
6H
8(OH)
4, or [–(CH(OH)–)2–CH
2–]2.
2-(Ethylamino)-1,2-diphenylethanone is a chemical compound which was first invented in 1955, researched by ICI in 1969 as an antidepressant, and subsequently claimed by AstraZeneca as an inhibitor of the enzyme 11β-Hydroxysteroid dehydrogenase type 1. No other pharmacological data has been disclosed, though its chemical structure closely resembles that of certain designer drug compounds such as ephenidine and N-ethylhexedrone.
References
- ↑ Richard Silverman, The Organic Chemistry of Drug Design and Drug Action, Second Edition, 2004
- ↑ Nathan Brown. Bioisosteres in Medicinal Chemistry. Wiley-VCH, 2012, p. 237. ISBN 978-3-527-33015-7
- ↑ Irving Langmuir. Isomorphism, isosterism and covalence. J. Am. Chem. Soc.1919, 41, 1543-1559. doi : 10.1021/ja02231a009
- ↑ Mukesh Doble, Anil Kumar Kruthiventi, Vilas Gajanan. Biotransformations and Bioprocesses. CRC Press, 2004, p. 60. ISBN 0-8247-4775-5
- ↑ H. Erlenmeyer, Ernst Willi: Zusammenhänge zwischen Konstitution und Wirkung bei Pyrazolonderivaten. In: Helvetica Chimica Acta. 18, 1935, S. 740, doi : 10.1002/hlca.193501801101.
- ↑ Hans Erlenmeyer, Martin Leo: Über Pseudoatome. In: Helvetica Chimica Acta. 15, 1932, S. 1171, doi : 10.1002/hlca.193201501132.
 | This article about theoretical chemistry is a stub. You can help Wikipedia by expanding it. |