In chemistry, isomers are ions or molecules with identical formulas but distinct structures. Isomers do not share similar properties. Two main forms of isomerism are structural stereoisomerism. Structural isomers differ in terms of the connectivity of all constituent atoms. A simple example of isomerism is given by propanol: It has the formula C3H8O and occurs as two isomers: propan-1-ol and propan-2-ol These two molecules are position isomers of each other, because the position of the hydroxy group differs between the two: It is attached to an end carbon in the first isomer, to the center carbon in the second. There is another isomer of C3H8O that has different properties: methoxyethane. Unlike the isomers of propanol, methoxyethane has an oxygen connected to two carbons rather than to one carbon and one hydrogen. Methoxyethane is an ether, not an alcohol, because it lacks a hydroxyl group, it has chemical properties more similar to other ethers than to either of the above alcohol isomers. Propadiene and propyne are examples of isomers containing different bond types.
Propadiene contains two double bonds. Tautomers are structural isomers which interconvert, so that two or more species co-exist in equilibria such as H–X–Y=Z ⇌ X=Y–Z–H. Important examples are keto-enol tautomerism and the equilibrium between neutral and zwitterionic forms of an amino acid. Stereoisomers have the same bond connectivity but different geometries. Two broad classes of stereoisomers are recognized: diastereomers. Enantiomers are non-superposable mirror-images of each other. Diastereomers are not. Enantiomers always contain chiral centers; some diastereomers are chiral and some are not. Another type of isomer, conformational isomers, may be rotamers, diastereomers, or enantiomers depending on the compound. For example, ortho- position-locked biphenyl systems have enantiomers. E/Z isomers, which have restricted rotation at a double bond, are configurational isomers, they are classified as diastereomers. E/Z notation depicts absolute stereochemistry, an unambiguous descriptor based on CIP priorities.
"Cis–trans isomers" are used to describe any molecules with restricted rotation in the molecule. For alkenes, these descriptors describe; this terminology is problematic for double bonds that have more than two substituents. An obsolete term for cis–trans isomerism is "geometric isomerism". For alkenes with more than two substituents, E-Z notation is used instead of cis and trans. If possible, E and Z is preferred in compounds with two substituents. Cis and trans isomers occur in inorganic coordination compounds, such as square planar MX2Y2 complexes and octahedral MX4Y2 complexes. A related type of geometric isomerism is facial–meridional isomerism in octahedral MX3Y3 complexes, in which each set of three identical ligands either occupies one face of the octahedron or is situated on one meridian of the octahedron. Although conformers can be referred to as stereoisomers, they are isolable in pure form. While structural isomers have different chemical properties, stereoisomers behave identically in most chemical reactions, except in their reaction with other stereoisomers.
Enzymes, can distinguish between different enantiomers of a compound, organisms prefer one isomer over the other. Enantiomers differ in the sign of their optical rotation of polarized light, are therefore sometimes described as optical isomers; however this term is ill-defined and has been used to describe other stereoisomers as well as enantiomers. Its use is therefore discouraged and the molecules should instead be described as either enantiomers or diastereomers as appropriate. Isomerization is the process by which one molecule is transformed into another molecule that has the same atoms, but the atoms are rearranged. In some molecules and under some conditions, isomerization occurs spontaneously. Many isomers are equal or equal in bond energy, so exist in equal amounts, provided that they can interconvert freely, the energy barrier between the two isomers is not too high; when the isomerization occurs intramolecularly, it is considered a rearrangement reaction. An example of an organometallic isomerization is the production of decaphenylferrocene, from its linkage isomer.
Synthesis of fumaric acidIndustrial synthesis of fumaric acid proceeds via the cis-trans isomerization of maleic acid: Isomers having different medical properties are common. In substituted xanthines, found in chocolate, is a vasodilator with some effects in common with caffeine. Another example of this occurs in the phenethylamine-based stimulant drugs. Phentermine is a non-chiral compound with a weaker effect than that of amphetamine, it has mild or no stimulant properties. However, a different atomic arrangement gives dextromethamphetamine, a stronger stimulant than amphetamine. In medicinal chemistry and biochemistry, enantiomers are a special concern because they may possess quite different biological activity. Many preparative procedures afford a mixture of equal amounts of both enantiomeric forms. In some cases, the enantiomer
Ellsworth Place is a 350,000-square-foot, six-story, enclosed shopping mall in downtown Silver Spring, Maryland. It opened as City Place Mall on April 2, 1992, is located at the intersection of Fenton Street and Colesville Road. Dave and Buster's opened in November 2016; the mall is located near center of intense development and redevelopment occurring in downtown Silver Spring. Current Ellsworth Place anchors include Burlington Coat Factory, Michaels, Ross Dress for Less and TJMaxx. An initial redevelopment in the early 2000s saw the addition of a row of street-level shops, including PNC Bank, Noodles & Company, Chipotle Mexican Grill, Ben & Jerry's; the building that houses the mall was a Hecht Company department store, the first suburban Washington, D. C. branch of that company, which opened in 1947. From its start, the mall included "upscale" discount stores, including original tenants Nordstrom Rack and Ross Dress for Less; the mall included an AMC movie theater on its fifth floor, but it closed shortly after a 20-screen Consolidated Theatres opened directly across Ellsworth Drive from Ellsworth Place.
In 2005 up-and-coming artist Rihanna performed a free concert at the mall, on a temporary stage built over the center court fountain. The event was sponsored by radio station Hot 99.5, was in support of her debut album Music of the Sun, with proceeds donated to victims of Hurricane Katrina. Downtown Silver Spring - City Place Mall website Petrie Richardson Ventures - Ellsworth Place website
The Fudge is a Dutch rock band formed in 2009 in Amsterdam by vocalist Midas Treub, guitarists Ruben van Wiggen and Max Westendorp, keyboardist Darius Timmer, bassist Shawn Moorhead and drummer Florent de Jong. In 2011 they have released their first single'Too busy being Delicious' followed by the release of their first album Morning Comes Again. Brought together by accident in 2009, six guys decided to embark on a musical adventure. During the first session the band explored each other’s preferences and it turned out that each member had his own musical influences; the Fudge knew that their diversity could be one of their main powers. A powerful and danceable sound in which Rock, Folk, Pop and Psychedelic are all morphed together in one, they dubbed it Magnetic Rock: loud and great to dance to. In their first year they played over 50 times in the Netherlands and they toured twice in Germany. In a short period the band accumulated quite a lot of prize money to record their debut album, they won the MakeMoreMusic competition, were selected to play on the prestigious Queens-night festival in The Hague and won the people’s choice award at the'Grote Prijs van Nederland' competition where they finished 2nd.
October 2011 saw the release of the Fudge first studio album titled'Morning Comes Again'. The album was recorded in Amsterdam; the band started the recording of their debut album with Jonas Filterborg. The record is mastered by Brad Blackwood. On 5 October the Fudge presented their debut album in a sold out Paradiso. In 2012 keyboardist Darius Timmer and bassist Shawn Moorhead left the band. Moorhead was replaced by Timothy Dunn. At the end of the year the band started working on their second studio album, released the single'Moviestar'. In March 2013 they announced they would "go our separate ways for the time being". However, the bandmembers have shown no interest in continuing as The Fudge so far. Vocalist Midas Treub is a solo artist. Midas Treub - lead vocals, guitar Max Westendorp - guitar, vocals Ruben van Wiggen - guitar, backing vocals Timothy Dunn - bass, backing vocals Florent de Jong - drums, backing vocals Darius Timmer - keys, backing vocals Shawn Moorhead - bass Morning Comes Again The name'The Fudge' refers to the English confectionery Fudge.
Like the confectionery, The Fudge is a mix of different people each having a different musical backgrounds and influences. The title of their debut single "Too busy being delicious" refers to what people say about and to then-bassist Shawn Moorhead when seen around women