chembox verifiedrevid 439048895 Name Cyclobutane ImageFile Cyclobutane2.svg ImageSize 100px ImageFileL1 Cyclobutane buckled 3D balls.png ImageSizeL1 100px ImageNameL1 Cyclobutane ImageFileR1 Cyclobutane buckled 3D vdW.png ImageSizeR1 100px ImageNameR1 Cyclobutane IUPACName cyclobutane Section1 Chembox Identifiers CASNo Ref cascite correct ?? CASNo 00287 23 0 SMILES C1CCC1 Section2 Chembox Properties Formula C sub 4 sub H sub 8 MolarMass 56.107 g mol MeltingPtC 91 BoilingPtC 12.5 Density 0.720 g cm ... Cyclobutene Cyclobutadiene Cyclobutane is an organic compound with the formula CH sub 2 sub sub 4 sub . Cyclobutane is a colourless gas and commercially available as a liquefied gas . Derivatives of cyclobutane are called cyclobutanes. Cyclobutane itself is of no commercial or biological significance ... bond energies than related linear or unstrained hydrocarbons, e.g. butane or cyclohexane . As such, cyclobutane is unstable above about 500 C. The four carbon atoms in cyclobutane are not coplanar ... http www.britannica.com EBchecked topic 148015 cyclobutane chemical compound Cycloalkanes Britannica ... 300px Pentacycloanammoxic acid Despite inherent strain the cyclobutane motif is indeed ... volume 419 pages 708 712 year 2002 doi 10.1038 nature01128 title Linearly concatenated cyclobutane ... 12384695 issue 6908 ref which is a ladderane composed of 5 fused cyclobutane units. The estimated strain in this compound is 3 times that of cyclobutane. The compound is found in bacteria performing ... Cyclobutane photodimers CPD s are formed by photochemical reaction s that result in the coupling ... 3734 pages 379 386 doi 10.1126 science.153.3734.379 title Cyclobutane Type Pyrimidine Dimers in Polynucleotides ... cyclobutane 1,1 carboxylic acid. Preparation Many methods exist for the preparation of cyclobutanes ... with reducing metals. See also Commons category Cyclobutane Butane References reflist External ... fr Cyclobutane it Ciclobutano lt Ciklobutanas mk nl Cyclobutaan ja pl ... more details
DISPLAYTITLE C sub 4 sub H sub 8 sub The molecular formula C sub 4 sub H sub 8 sub may refer to Butadiene resin Butene 2 butene Cyclobutane Isobutylene Methylcyclopropane MolFormDisambig el C4H8 fr C4H8 it C4H8 nl C4H8 ja C4H8 zh C4H8 ... more details
The DeMayo reaction is a photochemical reaction in which the enol of a 1,3 diketone reacts with an alkene or another species with a C C bond and the resulting cyclobutane ring undergoes a retro aldol reaction to yield a 1,5 diketone ref Li, Jie Jack. Named Reactions A Collection of Detailed Reaction Mechanisms. Springer 2003, p. 105. ref Image Demayo reaction.png The DeMayo reaction The net effect is to add the two carbon atoms in the C C double bond between the two carbonyl groups of the diketone. It is thus useful in syntheses both as a relatively selective way to join two parts of a molecule and as a way to apply the more developed chemistry of 1,3 diketone synthesis to 1,5 diketones. The first part is a 2 2 cycloaddition . The ensuing retro aldol cleavage is favored by the relative instability of the cyclobutane ring. External links 1. Some background and examples http rawalgroup.uchicago.edu litmeetings demayo.htm Link References Reflist Category Organic reactions ... more details
File Ladderane CM 3D balls.png thumb A simple ladderane, consisting of three fused cyclobutane rings A ladderane is an organic molecule containing two or more fused rings of cyclobutane . The name is a portmanteau because the serial cyclobutane rings look like a ladder and are singly bonded like alkane s. The chemical formula for a ladderane with n rings is Carbon C sub 2n 2 sub Hydrogen H sub 2n 6 sub . The geometry of ladderanes is highly strained because ligands to the carbon atoms cannot extend to their ideal angles. However, examples of ladderanes have been found in living organisms. ref name nouri a An example is pentacycloanammoxic acid ref cite journal journal Nature volume 419 pages 708 712 year 2002 doi 10.1038 nature01128 title Linearly concatenated cyclobutane lipids form a dense bacterial membrane author J. S. Sinninghe Damst , M. Strous, W. I. C. Rijpstra, E. C. Hopmans, J. A. J. Geenevasen, A. C. T. van Duin, L. A. van Niftrik and M. S. M. Jetten pmid 12384695 issue 6908 ref which is composed of 5 fused cyclobutane units. It is found in bacteria performing the anammox process where it forms part of a tight and very dense membrane believed to prevent the organism from losing the intermediate hydrazine which is involved in the production of nitrogen and water from nitrite ions and ammonia . ref cite journal title Enantioselective Synthesis of Pentacycloanammoxic Acid author Vincent Mascitti and E. J. Corey journal J. Am. Chem. Soc. year 2006 volume 128 issue 10 pages 3118 doi 10.1021 ja058370g pmid 16522072 ref Image PentacycloanammoxicAcid.png 300px Pentacycloanammoxic acid Ladderanes can be formed by the reduction of a carbon carbon double bond into a single bond, concomitant with the creation of a new carbon carbon bond to close the ring. Clarify date January 2011 ref name nouri a cite journal author Nouri, D H, Tantillo, D J title They Came from the Deep ... See also Cyclobutane Category Cycloalkanes Organic compound stub fr Ladderane nl Ladderaan zh ... more details
CPD can refer to any of the following US police departments Chicago Police Department Cincinnati Police Department Cleveland Police Department Columbus Police Department Certified Project Director as per IAPPM Town of Carmel Police Department , in New York Also CPD Certification Service Campaign for Peace and Democracy Cape Photographic Durchmusterung Centres of Plant Diversity Centre for Policy Dialogue Cephalo pelvic disproportion Cherry Poppin Daddies Chicago Park District Chronic pulmonary disease Collaborative Product Development Collaborative Professional Development Commission on Presidential Debates Committee on the Present Danger Concert of Parties for Democracy Conditional probability distribution Congress of People s Deputies AKA Congress of Soviets Contact potential difference Continuing Professional Development CPD gene , a human gene encoding the protein Carboxypeptidase D CPD Mark Critical Point Drying , a method of specimen preparation for electron microscopy Pyrimidine dimers Cyclobutane photodimers Cyclobutane Pyrimidine Dimer Cyclopentadiene CPD is the ICAO airline designator for Capital Airlines Limited Kenya PMD software Copy.2FPaste Detector .28CPD.29 PMD Copy&Paste Detector CPD disambiguation de CPD fr CPD it CPD ja CPD ru th CPD ... more details
The metal ion catalyzed bond Rearrangement reaction rearrangement reaction occurs with highly saturated organic ring molecules treated by Ag sup sup , Rh I , or Pd II ions ref Michael B. Smith, Jerry March, March s Advanced Organic Chemistry, 5 th Ed., John Wiley & Sons, Inc., 2001, p. 1459. ISBN 0 471 58589 0 ref . Two types of the reaction were noted 2 2 ring openings, and a conversion to another ring system Image Metal ion catalyzed sigma bond rearrangement.png 500px Scheme 1. Metal ion catalyzed bond rearrangement A mechanism for this rearrangement reaction is not completely understood, however some explanations were suggested. See also Cyclobutane Cubane Cuneane References references Organic reactions Category Rearrangement reactions ... more details
chembox verifiedrevid 442352986 ImageFile Benzocyclobutene.png ImageSize 140 ImageAlt Skeletal formula ImageFile1 Benzocyclobutene 3D balls.png ImageSize1 160 ImageAlt1 Ball and stick model IUPACName Benzocyclobutene OtherNames BCB Section1 Chembox Identifiers CASNo Ref cascite correct ?? CASNo 694 87 1 PubChem 24850072 SMILES C12 CC CC C1CC2 Section2 Chembox Properties C 8 H 8 Appearance Density 0.957 g cm sup 3 sup MeltingPt BoilingPtC 150 Solubility RefractIndex 1.541 Section3 Chembox Hazards MainHazards FlashPt Autoignition Benzocyclobutene BCB is a benzene ring fused to a cyclobutane ring. It has chemical formula carbon sub 8 sub hydrogen sub 8 sub . ref http www.sigmaaldrich.com catalog search ProductDetail ALDRICH 164410 164410 Benzocyclobutene 98 ref BCB is frequently used to create photosensitive polymer s. BCB based polymer dielectric s may be spun on or applied to various Wafer electronics substrate s for use in Micro Electro Mechanical Systems MEMS and microelectronics processing. Applications include wafer bonding, optical interconnects, low K dielectrics, or even intracortical neural implant s. See also Benzocyclopropene Benzocyclobutadiene References reflist Category Polycyclic aromatic hydrocarbons hydrocarbon stub de Benzocyclobuten el nl Benzocyclobuteen zh ... more details
chembox verifiedrevid 443546612 ImageFileL1 Cyclobutene.svg ImageSizeL1 ImageFileR1 Cyclobutene3D.png ImageSizeR1 IUPACName Cyclobutene OtherNames Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 63164 InChIKey CFBGXYDUODCMNS UHFFFAOYAN StdInChI Ref stdinchicite correct chemspider StdInChI 1S C4H6 c1 2 4 3 1 h1 2H,3 4H2 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey CFBGXYDUODCMNS UHFFFAOYSA N CASNo 822 35 5 EINECS 212 496 8 PubChem 69972 ChEBI Ref ebicite correct EBI ChEBI 51206 SMILES C 1 C CC 1 InChI 1 C4H6 c1 2 4 3 1 h1 2H,3 4H2 Section2 Chembox Properties Formula C sub 4 sub H sub 6 sub MolarMass 54.09 g mol Appearance Density 0.733 g cm sup 3 sup MeltingPt BoilingPt 2 C Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Cyclobutene is a cycloalkene . It is used in the chemical industry as a monomer for synthesis of some polymer s and for a range of chemical syntheses. See also Cyclobutane Cyclobutadiene Cyclobutyne Squaric acid External links http www.orgsyn.org orgsyn prep.asp?prep cv7p0117 Preparation of cyclobutene cycloalkenes Category Cycloalkenes Category Monomers hydrocarbon stub ar ca Ciclobut de Cyclobuten es Ciclobuteno fa fr Cyclobut ne it Ciclobutene hu Ciklobut n nl Cyclobuteen ja pt Ciclobuteno sr Ciklobuten zh ... more details
The Thorpe Ingold effect or gem dimethyl effect , or angle compression is an effect observed in organic chemistry where increasing the size of two substituents on a tetrahedral center leads to enhanced reactions between parts of the other two substituents. The effect was first reported by Beesley, Thorpe and Ingold in 1916 as part of a study of cyclization reaction s. ref cite journal author Beesley, Richard Moore coauthors Christopher Kelk Ingold Ingold, Christopher Kelk Jocelyn Field Thorpe Thorpe, Jocelyn Field title CXIX.?The formation and stability of spiro compounds. Part I. Spiro Compounds from cyclohexane journal J. Chem. Soc. , Trans. year 1915 volume 107 pages 1080 doi 10.1039 CT9150701080 ref A common application of this effect is addition of a quaternary carbon e.g., a geminal gem di methyl group in an alkyl chain to increase the reaction rate and or equilibrium constant of cyclization reactions. An example of this is an olefin metathesis reaction ref cite journal journal J. Org. Chem. volume 61 issue 25 pages 8746 8749 doi 10.1021 jo961600c title A Concise Total Synthesis of Dactylol via Ring Closing Metathesis last F rstner first A coauthors Langemann, K. year 1996 ref image tiemethathesis.PNG One proposed explanation for this effect is that the increased size of the substituents increases the angle between them. As a result, the angle between the other two substituents decreases. By moving them closer together, reactions between them are accelerated. It is thus a kinetic effect. image Thorpeingoldeffect.PNG The effect also has some thermodynamic contribution as the in silico strain energy decreases on going from cyclobutane to 1 methylcyclobutane and 1,1 dimethylcyclobutane by a value between 8 kcal mole ref Conventional Strain Energy in Dimethyl Substituted Cyclobutane and the gem Dimethyl Effect Ashley L. Ringer and David H. Magers J. Org. Chem. 2007 , 72, 2533 2537 DOI 10.1021 jo0624647 ref and 1.5 kcal mole. ref The gem Dimethyl Effect Revisited S ... more details
enzyme Name deoxyribodipyrimidine photo lyase EC number 4.1.99.3 CAS number 37290 70 3 IUBMB EC number 4 1 99 3 GO code 0003904 image width caption In enzymology , a deoxyribodipyrimidine photo lyase EC number 4.1.99.3 is an enzyme that catalysis catalyzes the chemical reaction cyclobutadipyrimidine in DNA math rightleftharpoons math 2 pyrimidine residues in DNA Hence, this enzyme has one substrate biochemistry substrate , cyclobutadipyrimidine in DNA , and one product chemistry product , pyrimidine residues in DNA . This enzyme belongs to the family of lyase s, specifically in the catch all class of carbon carbon lyases. The systematic name of this enzyme class is deoxyribocyclobutadipyrimidine pyrimidine lyase . Other names in common use include photoreactivating enzyme , DNA photolyase , DNA photoreactivating enzyme , DNA cyclobutane dipyrimidine photolyase , DNA photolyase , deoxyribonucleic photolyase , deoxyribodipyrimidine photolyase , photolyase , PRE , PhrB photolyase , deoxyribonucleic cyclobutane dipyrimidine photolyase , phr A photolyase , dipyrimidine photolyase photosensitive , and deoxyribonucleate pyrimidine dimer lyase photosensitive . It has 2 cofactor biochemistry cofactors FAD , and 5,10 Methenyltetrahydrofolate . Structural studies As of late 2007, 14 tertiary structure structures have been solved for this class of enzymes, with Protein Data Bank PDB accession codes PDB link 1DNP , PDB link 1IQR , PDB link 1IQU , PDB link 1OWL , PDB link 1OWM , PDB link 1OWN , PDB link 1OWO , PDB link 1OWP , PDB link 1QNF , PDB link 1TEZ , PDB link 2E0I , PDB link 2J07 , PDB link 2J08 , and PDB link 2J09 . References reflist 1 cite journal author Eker AP, Fichtinger Schepman AM date 1975 title Studies on a DNA photoreactivating enzyme from Streptomyces griseus II. Purification of the enzyme journal Biochim. Biophys. Acta. volume 378 pages 54&ndash 63 pmid 804322 issue 1 cite journal author Sancar GB, Smith FW, Reid R, Payne G, Levy M, Sancar A date 1987 title Ac ... more details
Image Cyclobutane buckled 3D balls.png thumb right Ball and stick model of cyclobutane Cycloalkanes also called naphthenes not to be confused with naphthalene are types of alkane s that have one or more rings of carbon atom s in the chemical structure of their molecule s. Alkanes are types of Organic compound organic hydrocarbon Chemical compound compounds that have only single chemical bond s in their chemical structure. Cycloalkanes consist of only carbon C and hydrogen H atoms and are saturated because there are no multiple C C bonds to Hydrogenation hydrogenate add more hydrogen to . A general chemical formula for cycloalkanes would be C sub n sub H sub 2 n 1 g sub where n number of C atoms and g number of rings in the molecule. Cycloalkanes with a single ring are named analogously to their normal alkane counterpart of the same carbon count cyclopropane , cyclobutane , cyclopentane , cyclohexane , etc. The larger cycloalkanes, with greater than 20 this could be less, now that I think about it the information in the paraffin article could be wrong, or not apply to the ring varieties carbon atoms are typically called cycloparaffins. Cycloalkanes are classified into small, common, medium, and large cycloalkanes, where cyclopropane and cyclobutane are the small ones, cyclopentane, cyclohexane, cycloheptane are the common ones, cyclooctane through cyclotridecane are the medium ones, and the rest are the larger ones. The need for the delineation between medium and large rings, is that ring strain is zero for all rings with 14 or more members, i.e. the large rings Nomenclature See also IUPAC nomenclature Image Norbornane 2D skeletal.png thumb Norbornane also called bicyclo 2.2.1 heptane The naming of polycyclic alkanes such as Bicyclic compound bicyclic alkanes and Spiro compound spiro alkanes is more complex, with the base name indicating the number of carbons in the ring ... to be around 120 kJ mol. Cyclobutane has the carbon atoms in a puckered square with approximately 90 ... more details
. Right Cyclobutane pyrimidine dimer. A cyclobutane pyrimidine dimer CPD contains a four membered ... Science year 1966 volume 153 issue 3734 pages 379 386 doi 10.1126 science.153.3734.379 title Cyclobutane ... 01 00245 7 author Vink Arie A., Roza Len year 2001 title Biological consequences of cyclobutane pyrimidine ... more details
Image Cyclopropane.png thumb 150px right Cyclopropane is the smallest alicyclic compound. An alicyclic compound is an organic compound that is both Aliphatic compound aliphatic and cyclic compound cyclic . They contain one or more all carbon rings which may be either saturation chemistry saturated or unsaturated, but do not have aromaticity aromatic character. ref GoldBookRef title Alicyclic compounds file A00216 year 1995 ref Alicyclic compounds may or may not have aliphatic side chains attached. The simplest alicyclic compounds are the monocyclic cycloalkane s cyclopropane , cyclobutane , cyclopentane , cyclohexane , cycloheptane , cyclooctane , cyclononane , cyclodecane , cycloundecane , cyclododecane , and so on. Bicyclic molecule Bicyclic alkanes include bicycloundecane and decalin . Polycyclic compound Polycyclic alkanes include cubane , basketane , and housane . Spiro compound s have two or more rings that are connected through only one carbon atom. An exocyclic group is always shown outside the ring structure, take for instance the exocyclic double bond on the left Image Exocyclic.png 200px Left exocyclic double bond Right regular double bond br style clear both See for an example isotoluene . The placement of double bonds in many alicyclic compounds can be predicted with Bredt s rule . The mode of ring closing in the formation of many alicyclic compounds can be predicted by Baldwin s rules . Cycloalkenes Image Cyclohexene structures.svg thumb right Cyclohexene is an alicyclic compound with a double bond. Monocyclic cycloalkene s are cyclopropene , cyclobutene , cyclopentene , cyclohexene , cycloheptene , cyclooctene , and so on. Bicyclic alkenes include norbornene and norbornadiene . References references Category Organic compounds Category Organic chemistry ar ca Compost alic clic cs Alicyklick slou eniny de Alicyclische Verbindungen et Alits klilised hendid el fa fr Compos alicyclique he ... more details
Unreferenced date December 2009 Image Alkyl cycloalkane.png thumb Methylcyclopropane , the simplest alkyl cycloalkane. Alkyl cycloalkanes are chemical compound s with an alkyl group with a single ring of carbon s to which hydrogen s are attached according to the formula C sub n sub H sub 2n sub . They are named analogously to their normal alkane counterpart of the same carbon count methylcyclopropane , methylcyclobutane , methylcyclopentane , methylcyclohexane , etc. Methylcycloalkanes are classed into compounds with small, normal and bigger cycloalkanes, where cyclopropane and cyclobutane are the small ones, cyclopentane , cyclohexane , cycloheptane are the normal ones and the rest are the bigger ones. TOC Nomenclature The naming of polycyclic alkanes is more complex, with the base name indicating the number of carbons in the ring system, a prefix indicating the number of rings e.g., bicyclo , and a numeric prefix before that indicating the number of carbons in each part of each ring, exclusive of vertices. For instance, a bicyclooctane which consists of a six member ring and a four member ring, which share two adjacent carbon atoms which form a shared edge, is 4.2.0 bicyclooctane. That part of the six member ring, exclusive of the shared edge has 4 carbons. That part of the four member ring, exclusive of the shared edge, has 2 carbons. The edge itself, exclusive of the two vertices that define it, has 0 carbons. Reactions The normal and the bigger alkylcycloalkanes are very stable like alkanes and their reactions cf. radicalic chain reactions are like alkanes. The small alkylcycloalkanes particularly alkylcyclopropane has a lower stability due to the Baeyer tension . They react similar to alkenes , though they don t react with the EA cf. electrophilic addition , but with the SN2 cf. nucleophilic substitution reaction mechanism. These reactions are both ring opening reactions and Cleavage crystal cleavage reactions. Typical compound The typical compound of the grou ... more details
chembox verifiedrevid 436868615 ImageFileL1 Perfluorocyclobutane.svg ImageFileR1 Perfluorocyclobutane 3D.png ImageSizeL1 125px ImageSizeR1 125px IUPACName Octafluorocyclobutane OtherNames Freon C 318, perfluorocyclobutane Section1 Chembox Identifiers CASNo Ref cascite correct CAS CASNo 115 25 3 EINECS 204 075 2 PubChem SMILES Section2 Chembox Properties Formula C sub 4 sub F sub 8 sub MolarMass 200.03 g mol Appearance colourless gas Density 1.654 at 20 C 8.460 kg m 3 gas at 15 C and 1 atm , 6.91 times air MeltingPt 40.1 C BoilingPt 6 C Solubility low Section7 Chembox Hazards MainHazards FlashPt Autoignition Octafluorocyclobutane , or perfluorocyclobutane , C sub 4 sub F sub 8 sub , is an Organofluorine chemistry organofluorine compound which enjoys several niche applications. It is related to cyclobutane by replacement of all C H bonds with C F bond s. Octafluorocyclobutane is produced by the dimerization of tetrafluoroethylene and the reductive coupling of 1,2 dichloro 1,1,2,2 tetrafluoroethane . ref name Ullmann G. Siegemund, W. Schwertfeger, A. Feiring, B. Smart, F. Behr, H. Vogel, B. McKusick Fluorine Compounds, Organic in Ullmann s Encyclopedia of Industrial Chemistry 2005, Wiley VCH, Weinheim. DOI 10.1002 14356007.a11 349 ref Applications In the production semiconductor materials and devices, octafluorocyclobutane serves as a deposition gas and etchant . It has also been investigated as a refrigerant in specialised applications, as a replacement for ozone depleting chlorofluorocarbon refrigerants. Exploiting its volatility and chemical inertness, octafluorocyclobutane may be found in some aerosolized foods. It is listed by the Codex Alimentarius under number E946. It is investigated as a possible replacement for sulfur hexafluoride as a dielectric gas . References references Appendix Its critical point thermodynamics critical point is at 115.3 C and 2.79 MPa. Category Organofluorides Category Aerosol propellants Category Refrigerants Category Dielectric gases ... more details
Pfam box Symbol DNA photolyase Name DNA photolyase image width caption Pfam PF00875 InterPro IPR006050 SMART Prosite PDOC00331 SCOP 1qnf TCDB OPM family OPM protein DNA photolyase is an evolutionary conserved protein domain . This domain binds a light harvesting cofactor. ref name pmid9360600 cite journal author Tamada T, Kitadokoro K, Higuchi Y, Inaka K, Yasui A, de Ruiter PE, Eker AP, Miki K title Crystal structure of DNA photolyase from Anacystis nidulans journal Nat. Struct. Biol. volume 4 issue 11 pages 887 91 year 1997 month November pmid 9360600 doi 10.1038 nsb1197 887 url issn ref Deoxyribodipyrimidine photolyase DNA photolyase is a DNA repair enzyme. It binds to UV damaged DNA containing pyrimidine dimers and, upon absorbing a near UV photon 300 to 500 nm , breaks the cyclobutane ring joining the two pyrimidine s of the dimer. DNA photolyase is an enzyme that requires two chromophore cofactors for its activity a reduced FAD FADH2 and either 5,10 methenyltetrahydrofolate 5,10 Methenyltetrahydrofolate 5,10 MTFH or an oxidized 8 hydroxy 5 deazaflavin 8 HDF derivative Coenzyme F420 F420 . The folate or deazaflavin chromophore appears to function as an antenna, while the FADH2 chromophore is thought to be responsible for electron transfer. On the basis of sequence similarities DNA photolyases can be grouped into two classes. The first class contains enzymes from Gram negative and Gram positive bacteria, the halophilic archaebacteria Halobacterium halobium, fungi and plants. Class 1 enzymes bind either 5,10 MTHF Escherichia coli E. coli , fungi, etc. or 8 HDF Streptomyces griseus S. griseus , Halobacterium H. halobium . Proteins containing this domain also include Arabidopsis thaliana cryptochromes 1 CRY1 and 2 CRY2 , which are blue light photoreceptors that mediate blue light induced gene expression. Examples Human proteins containing this domain include CRY1 CRY2 References Reflist InterPro content IPR005101 protein stub Category Protein domains ... more details
state. image NgroupP11.jpg center 100px NGP by a cyclopropane, cyclobutane or a homoallyl group If Cyclopropylmethyl ... alcohol, 47 cyclobutane cyclobutanol and 5 homoallyl alcohol but 3 enol is obtained. This is because ... more details
like transition state. An example of the Cope rearrangement is the expansion of a cyclobutane ... thermal conditions. The driving force of the reaction is the loss of strain from the cyclobutane ring ... more details
. The more common covalent linkage involves the formation of a cyclobutane bridge. Photolyases have .... Image direct DNA damage.png thumb left 410px A UV radiation induced thymine thymine cyclobutane dimer ... more details
Image direct DNA damage.png thumb right 500px Direct DNA damage The UV photon is directly absorbed by the DNA left . One of the possible reactions from the excited state is the formation of a thymine thymine cyclobutane dimer right . The direct DNA damage leads to sunburn, causing an increase in melanin production, thereby leading to a long lasting tan. However, it is responsible for only 8 of all melanoma. Direct DNA damage can occur when DNA directly absorbs the UV B photon. UVB light causes thymine base pairs next to each other in genetic sequences to bond together into pyrimidine dimers , a disruption in the strand, which reproductive enzymes cannot copy. It causes sunburn and it triggers the production of melanin . ref name Parrish1982 cite journal author John A. Parrish, Kurt F. Jaenicke, R. Rox Anderson title ERYTHEMA AND MELANOGENESIS ACTION SPECTRA OF NORMAL HUMAN SKIN url http www.blackwell synergy.com doi abs 10.1111 j.1751 1097.1982.tb04362.x journal Photochemistry and Photobiology volume 36 issue 2 pages 187 191 year 1982 doi 10.1111 j.1751 1097.1982.tb04362.x pmid 7122713 ref Other names for the direct DNA damage are ref http www.osti.gov bridge servlets purl 6106470 Syh9i7 6106470.PDF Effects of Solar Ultraviolet Photons on Mammalian Cell DNA ref thymine dimer s pyrimidine dimer s Cyclobutane Pyrimidine Dimers CPD s . UV endonuclease sensitive sites ESS Due to the excellent photochemical properties of DNA, this nature made molecule is damaged only by a tiny fraction of the absorbed photons. DNA transforms more than 99.9 of the photons into harmless heat ref name DNA IC But the damage from the remaining 0.1 of the photons is still enough to cause sunburn . ref name Parrish1982 The transformation of excitation energy into harmless heat occurs via a photochemical process called internal conversion chemistry internal conversion . In DNA, this internal conversion chemistry internal conversion is extremely fast and therefore efficient. This ultrafast subpic ... more details
chembox verifiedrevid 444653737 ImageFileL1 Ref chemboximage correct ?? ImageFileL1 Cyclopentane2d.png ImageSizeL1 100px ImageAltL1 Skeletal formula ImageFileR1 Cyclopentane3d.png ImageSizeR1 110px ImageAltR1 Space filling model IUPACName Cyclopentane OtherNames pentamethylene Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 8896 InChI 1 C5H10 c1 2 4 5 3 1 h1 5H2 InChIKey RGSFGYAAUTVSQA UHFFFAOYAL StdInChI Ref stdinchicite correct chemspider StdInChI 1S C5H10 c1 2 4 5 3 1 h1 5H2 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey RGSFGYAAUTVSQA UHFFFAOYSA N CASNo Ref cascite correct CAS CASNo 287 92 3 PubChem 9253 ChEBI Ref ebicite correct EBI ChEBI 23492 SMILES C1CCCC1 RTECS GY2390000 Section2 Chembox Properties Formula C sub 5 sub H sub 10 sub MolarMass 70.1 g mol Appearance clear, colorless liquid Density 0.751 g cm sup 3 sup MeltingPt 94 C BoilingPtC 49 Solubility pKa 45 pKb Section3 Chembox Hazards MainHazards FlashPt Autoignition Section8 Chembox Related OtherCpds cyclopropane , cyclobutane , cyclohexane Cyclopentane is a highly flammable alicyclic compound alicyclic hydrocarbon with chemical formula carbon sub 5 sub hydrogen sub 10 sub and CAS number 287 92 3, consisting of a ring of five carbon atoms each bonded with two hydrogen atoms above and below the plane. It occurs as a colorless liquid with a petrol like odor . Its melting point is 94 C and its boiling point is 49 C. Cyclopentane is in the class of cycloalkane s, being alkane s that have one or more Carbon ring rings of carbon atoms . Image Cyclopentane3D.png thumb left 120px The typical structure of cyclopentane is the envelope conformation. Industrial usage Cyclopentane is used in the manufacture of chemical synthesis synthetic resin s and rubber adhesive s and also as a blowing agent in the manufacture of polyurethane insulating foam, as found in many domestic appliances such as refrigerator s and freezer s, replacing environmentally damaging alt ... more details
chembox Watchedfields changed verifiedrevid 450502843 Reference ref name Merck Merck Index , 11th Edition, 4442 ref ref name Science Science. 1969 , vol. 166 pp.1010 1012 ref Name Grandisol ImageFile Grandisol.png ImageSize 120px ImageName IUPACName small 1 R ,2 S 1 2 Hydroxyethyl 1 methyl br 2 isopropenylcyclobutane small OtherNames small cis 2 Isopropenyl 1 methylcyclobutaneethanol small Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 147990 PubChem 169202 InChI 1 C10H18O c1 8 2 9 4 5 10 9,3 6 7 11 h9,11H,1,4 7H2,2 3H3 t9 ,10 m0 s1 InChIKey SJKPJXGGNKMRPD VHSXEESVBS StdInChI Ref stdinchicite correct chemspider StdInChI 1S C10H18O c1 8 2 9 4 5 10 9,3 6 7 11 h9,11H,1,4 7H2,2 3H3 t9 ,10 m0 s1 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey SJKPJXGGNKMRPD VHSXEESVSA N CASNo Ref cascite correct ?? CASNo 28117 21 7 SMILES OCC C 1 C C H C C C CC1 Section2 Chembox Properties Formula C sub 10 sub H sub 18 sub O MolarMass 154.25 g mol Density MeltingPt 25 C BoilingPt 50 60 C at 1 mmHg Grandisol is a natural organic compound with the molecular formula C sub 10 sub H sub 18 sub O. It is a monoterpene containing a cyclobutane ring, an alcohol group, an alkene group and two Chirality chemistry chiral centers one of which is quaternary . Grandisol is a pheromone primarily important as the sex attractant of the cotton boll weevil Anthonomus grandis , from which it gets its name. ref name Merck It is also a pheromone for other related insects. The cotton boll weevil is an agricultural pest that can cause significant economic damage if not controlled. Grandisol is the major constituent of the mixture known as grandlure , which is used to protect cotton crops from the boll weevil. ref name Merck Synthesis Grandisol was first isolated, identified, and synthesized by J. Tumlinson et al . at Mississippi State University in 1969. ref name Science The most recent and highest yielding synthetic route to grandisol was repor ... more details
File Dictyophora indusiata Feb 2010.JPG thumb Phallus indusiatus . Cooktown, Queensland , Australia. Produces two novel sesquiterpenes Sesquiterpenes are a class of terpene s that consist of three isoprene units and have the molecular formula C sub 15 sub H sub 24 sub . Like monoterpenes , sesquiterpenes may be acyclic or contain rings, including many unique combinations. Biochemical modifications such as redox oxidation or rearrangement reaction rearrangement produce the related sesquiterpenoids . Sesquiterpenes are found naturally in plants and insects, as semiochemical s, e.g. defensive agents or pheromones. Acyclic When geranyl pyrophosphate reacts with isopentenyl pyrophosphate , the result is the 15 carbon farnesyl pyrophosphate , which is an intermediate in the biosynthesis of sesquiterpenes such as farnesene . Oxidation can then provide sesquiterpenoids such as farnesol . Image Farnesyl pyrophosphate.png thumb 300px none Farnesyl pyrophosphate Monocyclic With the increased chain length and additional double bond, the number of possible ways that cyclization can occur is also increased, and there exists a wide variety of cyclic sesquiterpenes. In addition to common six membered ring systems such as is found in zingiberene , a constituent of the oil from ginger , cyclization of one end of the chain to the other end can lead to macrocyclic rings such as humulene . Bicyclic image Cadinene.png thumb right 100px &delta Cadinene, a sesquiterpene In addition to common six membered rings such as in the cadinene s, one classic bicyclic sesquiterpene is caryophyllene , from the oil of clove s, which has a nine membered ring and cyclobutane ring. Additional unsaturation provides aromatic bicyclic sesquiterpenoids such as vetivazulene and guaiazulene . Tricyclic With the addition of a third ring, the possible structures become increasingly varied. Examples include longifolene , copaene and the alcohol patchoulol . Dictyophorine A and B Two novel sesquiterpene s have been ... more details
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