The polyynes are a group of organic compounds with alternating single and triple bonds, for example buta-1,3-diyne (diacetylene), C4H2. An organic compound is any member of a large class of Chemical compounds whose Molecules contain Carbon. Diacetylene (also known as butadiyne) with the formula C4H2 is a highly unsaturated Hydrocarbon that contains one Single bond
Along with cumulenes, polyynes are distinguished from other organic chains by their rigidity, which makes them promising for molecular nanotechnology. A cumulene is a Chemical compound with three or more cumulative (consecutive double bonds, for example 123-butatriene (which is also just called cumulene Molecular nanotechnology (MNT is the concept of engineering functional mechanical systems at the molecular scale Polyynes are found in interstellar molecular clouds where hydrogen is scarce. See also Solar nebula A molecular cloud, sometimes called a stellar nursery if Star formation is occurring within is a type of Interstellar
Cyanopolyynes such as cyanoacetylene, C3HN, (expanding the definition to any triple bond functional group) are particularly common in these interstellar clouds. They were first detected around 1970. Cyanoacetylene is one of the molecules that is known to exist because of the Miller-Urey experiment. The Miller-Urey experiment (or Urey-Miller experiment) was an Experiment that simulated hypothetical conditions present on the Early Earth and tested This molecule appears in the large glass container, where water is being boiled.
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Naturally occurring polyynes
Naturally occurring polyynes exist,[1] and many are associated with medicinal properties. Medicine is the art and science of healing It encompasses a range of Health care practices evolved to maintain and restore Human Health by the The acetylenic fatty acid 1 (scheme 1) is isolated from the root bark of the legume Paramacrolobium caeruleum of the Showy Mistletoe Family. Mistletoe is the common name for a group of hemi-parasitic Plants in the order Santalales that grow attached to and within the The stems and leaves of members of this family have been used for the treatment of cancer in Java and Indonesia. Cancer (medical term Malignant Neoplasm) is a class of Diseases in which a group of cells display uncontrolled
The naturally occurring pigment thiarubrine B (2) has been isolated from the giant ragweed (Ambrosia trifida). For the drug referred to as "pigment" see Black tar heroin. Ragweeds ( Ambrosia) also called bitterweeds and bloodweeds, are a Genus of flowering Plants from the sunflower Plants containing this type of compound have been used to treat skin infections and intestinal parasites by native people in Africa and Canada.
The inner bark and roots of Devil's club is used by native Americans to treat a variety of ailments. Devil's Club ( Oplopanax horridus, Araliaceae; syn Echinopanax horridus, Fatsia horrida) is a large Shrub native to One of the polyynes isolated is oplopandiolacetate (3). Dihydromatricaria acid (4) is a polyyne obtained from the soldier beetle. The soldier beetles, Cantharidae, are relatively soft-bodied straight sided Beetles related to the Lampyridae or Firefly family but being
Because of the potential medicinal properties of these polyynes, their synthetic pathways are being studied with the hope that these can be replicated industrially by organic synthesis. Organic synthesis is a special branch of Chemical synthesis and is concerned with the construction of Organic compounds via Organic reactions Organic Many such procedures involve a Cadiot–Chodkiewicz coupling. The Cadiot-Chodkiewicz coupling in Organic chemistry is a Coupling reaction between a terminal Alkyne and a Haloalkyne Catalyzed
Polyynes in space
The octatetraynyl radicals and hexatriynyl radicals together with their ions are detected in space. Octatetraynyl radical (C8H is an organic Free radical with eight Carbon atoms linked in a chain with alternating Single bonds and The hexatriynyl radical, C6H is an organic radical molecule consisting of a chain of six carbon atoms terminated by a hydrogen
References
- ^ Synthesis of Naturally Occurring Polyynes Annabelle L. K. Shi Shun, Rik R. Tykwinski Angewandte Chemie International Edition Volume 45, Issue 7 , Pages 1034 - 1057 2006 Abstract
External links
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