Complex compounds where two cyclic molecules are interlaced together as links in a chain. They have potential use in NANOTECHNOLOGY.
CIRCULAR DNA that is interlaced together as links in a chain. It is used as an assay for the activity of DNA TOPOISOMERASES. Catenated DNA is attached loop to loop in contrast to CONCATENATED DNA which is attached end to end.
A group of compounds with three aromatic rings joined in linear arrangement.
Complex compounds in which a dumbbell shaped molecule is encircled by a macrocycle. They are named after rota (wheel) and axis (axle). Notation with a prefix is used to indicate the number of interlocked components. They have potential use in NANOTECHNOLOGY. Rotaxanes have been made with CYCLODEXTRINS and CYCLIC ETHERS.
Any of the covalently closed DNA molecules found in bacteria, many viruses, mitochondria, plastids, and plasmids. Small, polydisperse circular DNA's have also been observed in a number of eukaryotic organisms and are suggested to have homology with chromosomal DNA and the capacity to be inserted into, and excised from, chromosomal DNA. It is a fragment of DNA formed by a process of looping out and deletion, containing a constant region of the mu heavy chain and the 3'-part of the mu switch region. Circular DNA is a normal product of rearrangement among gene segments encoding the variable regions of immunoglobulin light and heavy chains, as well as the T-cell receptor. (Riger et al., Glossary of Genetics, 5th ed & Segen, Dictionary of Modern Medicine, 1992)
A genus of facultatively anaerobic coccoid ARCHAEA, in the family SULFOLOBACEAE. Cells are highly irregular in shape and thermoacidophilic. Lithotrophic growth occurs aerobically via sulfur oxidation in some species. Distribution includes solfataric springs and fields, mudholes, and geothermically heated acidic marine environments.
A strictly autotrophic species of bacteria that oxidizes sulfur and thiosulfate to sulfuric acid. It was formerly called Thiobacillus thiooxidans.
Circular duplex DNA isolated from viruses, bacteria and mitochondria in supercoiled or supertwisted form. This superhelical DNA is endowed with free energy. During transcription, the magnitude of RNA initiation is proportional to the DNA superhelicity.
The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.
DNA TOPOISOMERASES that catalyze ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. These enzymes bring about relaxation of the supercoiled DNA and resolution of a knotted circular DNA duplex.
Enzymes that recombine DNA segments by a process which involves the formation of a synapse between two DNA helices, the cleavage of single strands from each DNA helix and the ligation of a DNA strand from one DNA helix to the other. The resulting DNA structure is called a Holliday junction which can be resolved by DNA REPLICATION or by HOLLIDAY JUNCTION RESOLVASES.
A bacterial DNA topoisomerase II that catalyzes ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. Topoisomerase IV binds to DNA as a heterotetramer consisting 2 parC and 2 parE subunits. Topoisomerase IV is a decatenating enzyme that resolves interlinked daughter chromosomes following DNA replication.
A representation, generally small in scale, to show the structure, construction, or appearance of something. (From Random House Unabridged Dictionary, 2d ed)

A reversible synthetic rotary molecular motor. (1/10)

The circumrotation of a submolecular fragment in either direction in a synthetic molecular structure is described. The movement of a small ring around a larger one occurs through positional displacements arising from biased Brownian motion that are kinetically captured and then directionally released. The sense of rotation is governed solely by the order in which a series of orthogonal chemical transformations is performed. The minimalist nature of the [2]catenane flashing ratchet design permits certain mechanistic comparisons with the Smoluchowski-Feynman ratchet and pawl. Even when no work has to be done against an opposing force and no net energy is used to power the motion, a finite conversion of energy is intrinsically required for the molecular motor to undergo directional rotation. Nondirectional rotation has no such requirement.  (+info)

Chemical peristalsis. (2/10)

Molecules that emulate in part the remarkable capabilities of protein motors were recently chemically synthesized. A promising approach is based on physically interlocked macromolecular complexes such as rotaxanes and catenanes. Using the latter, Leigh et al. [Leigh, D. A., Wong, J. K. Y., Dehez, F. & Zerbetto, F. (2003) Nature 424, 174-179] constructed a molecular rotor in which two small rings are induced by pulses of light to move unidirectionally around a third, larger ring. The mechanism is similar to that by which a peristaltic pump operates. Unlike macroscopic peristalsis, however, in which a traveling wave forces material through a series of one-way valves, the chemical peristaltic mechanism does not directly cause the small rings to move but only alters the energetics, with the motion itself arising by thermal activation over energy barriers. Engines operating by this mechanism are "Brownian" motors. Here we describe a minimal two-state mechanism for a catenane-based molecular motor. Although fluctuations caused by equilibrium processes cannot drive directed motion, nonequilibrium fluctuations, whether generated externally or by a far-from-equilibrium chemical reaction, can drive rotation even against an external torque. We discuss a possible architecture for input and output of information and energy between the motor and its environment and give a simple expression for the maximum thermodynamic efficiency. The proposed Brownian motor mechanism is consistent with the high efficiency observed by Yasuda et al. [Yasuda, Y., Noji, H., Kinoshita, K. & Yoshida, M. (1998) Cell 93, 1117-1124] for the F(1)-ATP synthase operating as an ATP-powered molecular rotor.  (+info)

Amplification of acetylcholine-binding catenanes from dynamic combinatorial libraries. (3/10)

Directed chemical synthesis can produce a vast range of molecular structures, but the intended product must be known at the outset. In contrast, evolution in nature can lead to efficient receptors and catalysts whose structures defy prediction. To access such unpredictable structures, we prepared dynamic combinatorial libraries in which reversibly binding building blocks assemble around a receptor target. We selected for an acetylcholine receptor by adding the neurotransmitter to solutions of dipeptide hydrazones [proline-phenylalanine or proline-(cyclohexyl)alanine], which reversibly combine through hydrazone linkages. At thermodynamic equilibrium, the dominant receptor structure was an elaborate [2]-catenane consisting of two interlocked macrocyclic trimers. This complex receptor with a 100 nM affinity for acetylcholine could be isolated on a preparative scale in 67% yield.  (+info)

Bovine mitochondrial peroxiredoxin III forms a two-ring catenane. (4/10)

A crystal structure is reported for the C168S mutant of a typical 2-Cys peroxiredoxin III (Prx III) from bovine mitochondria at a resolution of 3.3 A. Prx III is present as a two-ring catenane comprising two interlocking dodecameric toroids that are assembled from basic dimeric units. Each ring has an external diameter of 150 A and encompasses a central cavity that is 70 A in width. The concatenated dodecamers are inclined at an angle of 55 degrees, which provides a large contact surface between the rings. Dimer-dimer contacts involved in toroid formation are hydrophobic in nature, whereas the 12 areas of contact between interlocked rings arise from polar interactions. These two major modes of subunit interaction provide important insights into possible mechanisms of catenane formation.  (+info)

Dynamic donor-acceptor [2]catenanes. (5/10)

Donor-acceptor [2]catenanes based on cyclobis(paraquat-p-phenylene) as the pi-acceptor ring have been used prominently in the construction of functional molecular devices. We report here their thermodynamically controlled synthesis from isolated pi-donor and pi-acceptor rings under the catalytic influence of tetra butylammonium iodide. The initial nucleophilic attack of iodide ion, which opens up the pi-acceptor ring, is followed by complexation to the pi-donor ring and the subsequent catenation of the pi-donor ring by the pi-acceptor ring [2]catenane. The reaction is general in scope and proceeds in high yields, without giving rise to side-products.  (+info)

A bistable poly[2]catenane forms nanosuperstructures. (6/10)

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A pseudocatenane structure formed between DNA and A cyclic bisintercalator. (7/10)

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[2]Catenanes decorated with porphyrin and [60]fullerene groups: design, convergent synthesis, and photoinduced processes. (8/10)

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A catenane is a type of molecular structure composed of two or more interlocked macrocyclic molecules, which are circular molecules that resemble rings. The term "catenane" comes from the Latin word "catena," meaning "chain." In a catenane, the rings are linked together in a chain-like fashion, but they are not chemically bonded to each other. Instead, they are held together by non-covalent interactions such as van der Waals forces or hydrogen bonds.

Catenanes have attracted significant interest from chemists and materials scientists due to their unique properties and potential applications in fields such as molecular machines, sensors, and drug delivery systems. They can be synthesized using various methods, including template-directed synthesis, where a template molecule is used to guide the formation of the interlocked rings.

In summary, catenanes are interlocked molecular structures composed of two or more macrocyclic rings that are held together by non-covalent interactions. They have potential applications in various fields and can be synthesized using different methods.

Catenated DNA refers to the linking or interlocking of two or more DNA molecules in a circular form, where the circles are topologically entangled. This occurs during DNA replication when the sister chromatids (identical copies of DNA) are formed and remain interlinked before they are separated during cell division. The term "catenane" is used to describe this interlocking structure. It is important to note that in linear DNA, the term "catenated" does not apply since there is no circular formation.

Anthracene is an organic compound with the chemical formula C6H6. It is a solid polycyclic aromatic hydrocarbon, and is composed of three benzene rings arranged in a linear fashion. Anthracene is used primarily for research purposes, including studying DNA damage and mutagenesis. It is not known to have any significant biological role or uses in medicine. Exposure to anthracene may occur through coal tar or coal tar pitch volatiles, but it does not have established medical definitions related to human health or disease.

I'm sorry for any confusion, but "rotaxanes" is not a term commonly used in medical definitions. Rotaxanes are actually a concept from the field of chemistry, specifically supramolecular chemistry. They refer to mechanically interlocked molecules, consisting of a dumbbell-shaped component with two large rings that thread onto the ends of the dumbbell and cannot come off, much like a macrocycle around an axle.

While rotaxanes have potential applications in various fields, including nanotechnology and materials science, they are not directly related to medical definitions or human health. If you have any questions about medical terminologies or concepts, I'd be happy to help with those instead!

Circular DNA is a type of DNA molecule that forms a closed loop, rather than the linear double helix structure commonly associated with DNA. This type of DNA is found in some viruses, plasmids (small extrachromosomal DNA molecules found in bacteria), and mitochondria and chloroplasts (organelles found in plant and animal cells).

Circular DNA is characterized by the absence of telomeres, which are the protective caps found on linear chromosomes. Instead, circular DNA has a specific sequence where the two ends join together, known as the origin of replication and the replication terminus. This structure allows for the DNA to be replicated efficiently and compactly within the cell.

Because of its circular nature, circular DNA is more resistant to degradation by enzymes that cut linear DNA, making it more stable in certain environments. Additionally, the ability to easily manipulate and clone circular DNA has made it a valuable tool in molecular biology and genetic engineering.

'Acidianus' is a genus of thermoacidophilic archaea, which are extremophiles that thrive in extremely acidic and hot environments. These microorganisms are commonly found in volcanic areas, such as sulfur-rich hot springs and deep-sea hydrothermal vents, where the pH levels can be as low as 0 and the temperature can reach up to 90°C (194°F).

The name 'Acidianus' is derived from the Latin word "acidus," meaning sour or acidic, and the Greek word "ianos," meaning belonging to. Therefore, the medical definition of 'Acidianus' refers to a genus of archaea that are adapted to survive in highly acidic environments.

These microorganisms have developed unique metabolic pathways to generate energy from sulfur compounds and other reduced substances present in their environment. They play an essential role in the global carbon and sulfur cycles, contributing to the breakdown of organic matter and the formation of elemental sulfur and sulfate.

Understanding the biology and ecology of 'Acidianus' and other thermoacidophilic archaea can provide insights into the limits of life on Earth and help us explore the potential for extraterrestrial life in extreme environments, such as those found on Mars or other planets.

'Acidithiobacillus thiooxidans' is a species of gram-negative, rod-shaped bacteria that derives energy from the oxidation of sulfur compounds. It is commonly found in acidic environments such as mines, caves, and soils with low pH levels. This bacterium plays a significant role in the biogeochemical cycling of sulfur and contributes to the natural attenuation of metal/sulfide-containing mine wastes. It can survive in extremely acidic conditions, with some strains able to tolerate pH levels as low as 0.5.

The primary metabolic process of 'Acidithiobacillus thiooxidans' involves the oxidation of elemental sulfur or reduced sulfur compounds (such as sulfide, thiosulfate, and tetrathionate) to produce sulfuric acid. This results in a decrease in pH and an increase in the acidity of its environment. The bacterium can also use ferrous iron as an electron donor for growth, further contributing to the acidification process.

'Acidithiobacillus thiooxidans' has potential applications in various industrial processes, including bioleaching (the extraction of metals from ores using microorganisms), bioremediation (the use of microorganisms to clean up contaminated environments), and wastewater treatment. However, its ability to acidify environments can also have negative consequences, such as accelerating corrosion in industrial settings or contributing to the formation of acid mine drainage.

Superhelical DNA refers to a type of DNA structure that is formed when the double helix is twisted around itself. This occurs due to the presence of negative supercoiling, which results in an overtwisted state that can be described as having a greater number of helical turns than a relaxed circular DNA molecule.

Superhelical DNA is often found in bacterial and viral genomes, where it plays important roles in compacting the genome into a smaller volume and facilitating processes such as replication and transcription. The degree of supercoiling can affect the structure and function of DNA, with varying levels of supercoiling influencing the accessibility of specific regions of the genome to proteins and other regulatory factors.

Superhelical DNA is typically maintained in a stable state by topoisomerase enzymes, which introduce or remove twists in the double helix to regulate its supercoiling level. Changes in supercoiling can have significant consequences for cellular processes, as they can impact the expression of genes and the regulation of chromosome structure and function.

Nucleic acid conformation refers to the three-dimensional structure that nucleic acids (DNA and RNA) adopt as a result of the bonding patterns between the atoms within the molecule. The primary structure of nucleic acids is determined by the sequence of nucleotides, while the conformation is influenced by factors such as the sugar-phosphate backbone, base stacking, and hydrogen bonding.

Two common conformations of DNA are the B-form and the A-form. The B-form is a right-handed helix with a diameter of about 20 Å and a pitch of 34 Å, while the A-form has a smaller diameter (about 18 Å) and a shorter pitch (about 25 Å). RNA typically adopts an A-form conformation.

The conformation of nucleic acids can have significant implications for their function, as it can affect their ability to interact with other molecules such as proteins or drugs. Understanding the conformational properties of nucleic acids is therefore an important area of research in molecular biology and medicine.

DNA topoisomerases are enzymes that regulate the topological state of DNA during various cellular processes such as replication, transcription, and repair. They do this by introducing temporary breaks in the DNA strands and allowing the strands to rotate around each other, thereby relieving torsional stress and supercoiling. Topoisomerases are classified into two types: type I and type II.

Type II topoisomerases are further divided into two subtypes: type IIA and type IIB. These enzymes function by forming a covalent bond with the DNA strands, cleaving them, and then passing another segment of DNA through the break before resealing the original strands. This process allows for the removal of both positive and negative supercoils from DNA as well as the separation of interlinked circular DNA molecules (catenanes) or knotted DNA structures.

Type II topoisomerases are essential for cell viability, and their dysfunction has been linked to various human diseases, including cancer and neurodegenerative disorders. They have also emerged as important targets for the development of anticancer drugs that inhibit their activity and induce DNA damage leading to cell death. Examples of type II topoisomerase inhibitors include etoposide, doxorubicin, and mitoxantrone.

Transposases are a type of enzyme that are involved in the process of transposition, which is the movement of a segment of DNA from one location within a genome to another. Transposases recognize and bind to specific sequences of DNA called inverted repeats that flank the mobile genetic element, or transposon, and catalyze the excision and integration of the transposon into a new location in the genome. This process can have significant consequences for the organization and regulation of genes within an organism's genome, and may contribute to genetic diversity and evolution.

DNA Topoisomerase IV is a type of enzyme that plays a crucial role in the relaxation and manipulation of supercoiled DNA during processes such as replication, transcription, and chromosome segregation. It functions by temporarily cleaving and rejoining the DNA strands to allow for the unlinking and separation of DNA molecules. This enzyme primarily targets double-stranded DNA and is especially important in bacteria, where it helps to resolve the topological challenges that arise during DNA replication and segregation of daughter chromosomes during cell division. Inhibition of DNA Topoisomerase IV has been explored as a strategy for developing antibacterial drugs, as this enzyme is essential for bacterial survival and is not found in humans.

Structural models in medicine and biology are theoretical or physical representations used to explain the arrangement, organization, and relationship of various components or parts of a living organism or its systems. These models can be conceptual, graphical, mathematical, or computational and are used to understand complex biological structures and processes, such as molecular interactions, cell signaling pathways, organ system functions, and whole-body physiology. Structural models help researchers and healthcare professionals form hypotheses, design experiments, interpret data, and develop interventions for various medical conditions and diseases.

... "catenane" in order to indicate how many rings are involved. Discrete catenanes up to a [7]catenane have been synthesised. ... Another family of catenanes are called pretzelanes or bridged [2]catenanes after their likeness to pretzels with a spacer ... When molecular recognition motifs exist in the finished catenane (usually those that were used to synthesize the catenane), the ... Li, J.; Nowak, P.; Fanlo-Virgos, H.; Otto, S. (2014). "Catenanes from Catenanes: Quantitative Assessment of Cooperativity in ...
"Guinness World Records certificate". catenane.net. Retrieved 26 May 2020. "Nanobot (Havana Parody) - A Capella Science ft. ... catenanes and molecular knots and some of the earliest synthetic molecular motors, molecular robots and functional nanomachines ...
Rotaxanes and catenanes beyond the small molecule". Chemical Society Reviews. 48 (19): 5016-5032. doi:10.1039/C8CS00888D. ISSN ... Schill, Gottfried (1971). Catenanes, Rotaxanes, and Knots (1st ed.). Academic Press. p. 204. ISBN 9781483275666. G. A. Breault ... Olympiadane Rotaxane Catenane Molecular knot Molecular Borromean rings Browne, Wesley R.; Feringa, Ben L. (2006). "Making ... This increased strength is demonstrated by the necessity of harsher conditions to remove a metal template ion from catenanes as ...
Gibson, Harry W.; Bheda, Mukesh C.; Engen, Paul T. (1994). "Rotaxanes, catenanes, polyrotaxanes, polycatenanes and related ... Gibson, Harry W.; Bheda, Mukesh C.; Engen, Paul T. (1994). "Rotaxanes, catenanes, polyrotaxanes, polycatenanes and related ... doi:10.1016/s0040-4020(01)96671-2. Schill, Gottfried; Logemann, Enno; Littke, Walter (August 1984). "Makrocyclen, Catenane und ...
Rotaxanes and catenanes beyond the small molecule". Chemical Society Reviews. 48 (19): 5016-5032. doi:10.1039/C8CS00888D. ISSN ...
Related compounds in organic chemistry are the catenanes. The notation sn stands for stereospecific numbering, and indicates a ...
These approaches have been particularly successful in preparing unpredictable Catenanes and other complex macrocycles including ... "Amplification of acetylcholine-binding catenanes from dynamic combinatorial libraries". Science. 308 (5722): 667-9. Bibcode: ...
... catenanes. Also the synthesis of [3]-catenanes, [5]-catenanes, [6]-catenanes and [7]-catenanes is reported in many articles. ... They are a class of catenanes where the number of macrocycles is greater than two and as catenanes they belong to the big ... The main difference between poly-[2]-catenanes and poly-[n]-catenanes is the repeating unit, as a monomer is for the polymer. ... and Polymeric Catenanes", Molecular Catenanes, Rotaxanes and Knots (1 ed.), Wiley, pp. 247-276, doi:10.1002/9783527613724.ch10 ...
Catenane Made to Order". Angewandte Chemie International Edition in English. 28 (10): 1396-1399. doi:10.1002/anie.198913961. ...
His Nobel Prize work was done in 1983, when he was the first to synthesize a catenane, a complex of two interlocking ring- ... He has described syntheses of catenanes and molecular knots based on coordination complexes. He was elected a correspondent ... "Rotaxanes and catenanes as prototypes of molecular machines and motors". Pure and Applied Chemistry. 75 (10): 1383-93. doi: ...
In the same year, Guillaume showed how the ability of the two rings in [2]catenane to rotate alone each other enables [2] ... De Bo, Guillaume; Zhang, Min (2020). "A Catenane as a Mechanical Protecting Group". J. Am. Chem. Soc. 142 (11): 5029-5033. doi: ... De Bo, Guillaume; Zhang, Min (2020). "A Catenane as a Mechanical Protecting Group". J. Am. Chem. Soc. 142 (11): 5029-5033. doi: ... catenane to be used as a mechanical protecting group via the diversion of technical forces away from a mechanically active ...
1989). "A [2] Catenane Made to Order". J. Angew. Chem. Int. Ed. 28 (10): 1396-1399. doi:10.1002/anie.198913961. Luo R, Gilson ... The major challenge for the synthesis of catenane is to interlock molecules in a controlled fashion. Stoddart and co-workers ... A notable example of applying π-π interactions in supramolecular assembly is the synthesis of catenane. ... catenane product. Noncovalent interaction Dispersion (chemistry) Cation-pi interaction Intercalation (biochemistry) ...
Levene, SD; Donahue, C; Boles, TC; Cozzarelli, NR (1995). "Analysis of the structure of dimeric DNA catenanes by electron ... when he collaborated with Nicholas Cozzarelli's group on the structure and properties of supercoiled DNA and DNA catenanes. ...
"Geometry and Physics of Catenanes Applied to the Study of DNA Replication". Biophysical Journal. 74 (6): 2815-2822. Bibcode: ...
Catenane Mechanically interlocked molecular architecture Molecular Borromean rings Molecular knots Polyrotaxane Bravo, José A ... Sauvage, J. P. (1999). "Transition Metal-Containing Rotaxanes and Catenanes in Motion: Toward Molecular Machines and Motors". ... Much of the research concerning rotaxanes and other mechanically interlocked molecular architectures, such as catenanes, has ...
To create catenanes, the cyclobis(paraquat-p-phenylene) can be used as a template to "thread" a crown ether with a π-donor ... A bistable catenane (a ring with two π-donor components) is already a simple example of a molecular switch. In the present ... The modifications include mechanically entrapped compounds such as catenanes and rotaxanes, molecular switches and larger ... Catenanes Prepared by Kinetically Controlled Reactions Involving Alkynes". Organic Letters. 8 (21): 4835-4838. doi:10.1021/ ...
1. [2]Rotaxanes and a [2]catenane made to order". Journal of the American Chemical Society. 114 (1): 193-218. doi:10.1021/ ...
1. [2]Rotaxanes and a [2]catenane made to order". Journal of the American Chemical Society. 114 (1): 193-218. doi:10.1021/ ... Her research looks to understand the structure of supramolecular systems (e.g. rotaxanes and catenanes). She is generally ... rotaxanes and catenanes. Slawin joined the University of St Andrews in 1999. She was made a professor in 2004, and serves as ...
The molecule is a linear pentacatenane or a [5]catenane. It was synthesized and named by Fraser Stoddart and coworkers in 1994 ... The molecule was designed without any practical use in mind, although other catenanes may have possible application to the ...
He has also synthesised catenanes and metal-containing polymers by dynamic ring opening polymerisation. Puddephatt was won ...
... les metallo-catenanes" [A new family of molecules: metallo-catenanes]. Tetrahedron Letters (in French). 24 (46): 5095-5098. doi ... Building upon the assembly of mechanically linked molecules such as catenanes and rotaxanes as developed by Jean-Pierre Sauvage ... Neal, E. A.; Goldup, S. M. (2014). "Chemical consequences of mechanical bonding in catenanes and rotaxanes: isomerism, ... primarily catenanes). While this type of rotation can not be accessed beyond the molecule itself (because the rings are ...
Catenane Möbius strip Nucleoid Plasmid Ribbon theory Rolling circle replication Topoisomerase Theta type replication This is ... In this particular experiment, when DNA gyrase alone were inhibited, most of the catenanes were unlinked. However, when ... catenanes' or topologically interlinked circles. The circles are not covalently linked, but cannot be separated because they ...
One on the synthesis of catenanes began with serious chemistry and gradually - imperceptibly - became less credible; it ...
... such as rotaxanes and catenanes. Illustrative, α-cyclodextrin form second-sphere coordination complex with tetrabromoaurate ...
Examples of mechanically interlocked molecular architectures include catenanes, rotaxanes, molecular knots, molecular Borromean ...
Examples of molecules for which there exist topoisomers include DNA, which can form knots, and catenanes. Each topoisomer of a ... Mechanically-interlocked molecular architectures Catenane Rotaxanes Molecular knot Molecular Borromean rings ^ New Molecular ... Topologies Beyond Catenanes and Rotaxanes Essay 2000 Theresa Chang American Chemical Society Online Article v t e v t e ( ...
Fujita, M.; Ogura, K (1996). "Supramolecular Self-Assembly of Macrocycles, Catenanes, and Cages through Coordination of ... Fujita, M.; Ogura, K (1996). "Supramolecular Self-Assembly of Macrocycles, Catenanes, and Cages through Coordination of ...
Catenane and Rotaxane molecules, and Molecular knot Interlock fabric, a double-knitted jersey fabric. Interlocking directorate ...
Cryptand Rotaxane Catenane Molecular knot Effective molarity Macrocyclic stereocontrol Macrocyclic ligand Hamilton-Miller, JM ( ...
An interwoven grid complex has been used to template the synthesis of a doubly-twisted [2]catenane (otherwise known as a ... catenane and a granny knot. In 2021, the first report of a 3 × 3 interwoven grid was published. It was used to template the ... Catenane with Twisted Rings, and a Molecular Granny Knot". Angewandte Chemie International Edition. 57 (42): 13833-13837. doi: ...
... "catenane" in order to indicate how many rings are involved. Discrete catenanes up to a [7]catenane have been synthesised. ... Another family of catenanes are called pretzelanes or bridged [2]catenanes after their likeness to pretzels with a spacer ... When molecular recognition motifs exist in the finished catenane (usually those that were used to synthesize the catenane), the ... Li, J.; Nowak, P.; Fanlo-Virgos, H.; Otto, S. (2014). "Catenanes from Catenanes: Quantitative Assessment of Cooperativity in ...
Syntheses of three-dimensional catenanes under kinetic control. Yong Wu, Qing Hui Guo*, Yunyan Qiu, Jacob A. Weber, Ryan M. ...
Molecular motion of donor-acceptor catenanes in water. Fabien B. L. Cougnon, Nandhini Ponnuswamy, G. Dan Pantos, Jeremy K M ... Cougnon, F. B. L., Ponnuswamy, N., Pantos, G. D., & Sanders, J. K. M. (2015). Molecular motion of donor-acceptor catenanes in ... Molecular motion of donor-acceptor catenanes in water. / Cougnon, Fabien B. L.; Ponnuswamy, Nandhini; Pantos, G. Dan et al. In ... Cougnon, FBL, Ponnuswamy, N, Pantos, GD & Sanders, JKM 2015, Molecular motion of donor-acceptor catenanes in water, Organic ...
What is Catenane and rotaxane?. Catenanes are two interlocked cycles, like two links in a chain, which cannot be separated ... What are Catenanes give examples?. Catenanes have been synthesized incorporating many functional units, including redox-active ... What are Catenanes in DNA replication?. Catenanes, or topologically linked circular molecules, were first extracted from living ... What is Catenanes in biology?. Brian Rogers 2022-10-25 • comments off ...
Catenanes, DNA. Catenated DNA. DNA Catenanes. DNA, Catanates. CIRCULAR DNA that is interlaced together as links in a chain. It ...
The self-assembly and dynamic properties of two new catenanes, (P. R. Ashton, C. L. Brown, E. J. T. Chrystal, K. P. Parry, M. ... The self-assembly and dynamic properties of two new catenanes. Molecular trains. ...
Bistable [2]Catenanes for Data Storage. September 28, 2023. *Author: ChemViews (Photo: Ⓒ Markus Breig/KIT) ...
By means of DFT calculations the aforementioned [3]catenanem+ and the inclusion complex ([TTF]2n+ C CBPQT4+)m+, where CBPQT is ... Despite the fact that this instability per se in the gase phase would make the [3]catenane dissociate, it does not since it ... Our results show the stabilization that the [TTF]n+ moieties experience when they are part of the [3]catenane, although these ... The Nature of the [TTF]·+··· [TTF]·+ Interactions in the [TTF]22+ Dimers Embedded in Charged [3]Catenanes: Room-Temperature ...
Simultaneous self-assembly of a [2]catenane, a trefoil knot, and a Solomon link from a simple pair of ligands. Angew. Chem. Int ... Rigid-strut-containing crown ethers and [2]catenanes for incorporation into metal-organic frameworks. Chem. Eur. J. 15, 13356- ... A metal-organic framework replete with ordered donor-acceptor catenanes. Chem. Commun. 46, 380-382 (2010). ...
E. Flapan, A knot theoretic approach to molecular chirality, in: Molecular Topology: Catenanes, Rotaxanes, and Knots, eds. J.-P ...
Catenanes and rotaxanes in motion: towards molecular machines Org.: Prof. Alan Francis Williams ...
J. 2015, 21, 7193-7210: "p-Conjugated [2]Catenanes based on Oligothiophenes and Phenanthrolines: Efficient Synthesis and ... 2007, 119, 367-372: "Oligothiophene-Based Catenanes: Synthesis and Electronic Properties of a Novel Conjugated Topological ...
Brown, C. L.; Jonas, U.; Preece, J. A.; Ringsdorf, H.; Seitz, M.; Stoddart, J. F.: Introduction of [2]Catenanes into Langmuir ...
... catenanes and Cyclic Oligo[2]catenanes Containing Alternating Topological and Covalent Bonds: Synthesis and Characterization. ... catenanes Containing Rigid Catenane Segments. Macromolecules 32, pp. 1737 - 1745 (1999) ...
The first crystal structures of a catenane and of a metalio-catenate are reported; upon complexation with Cu, there is a ... The first crystal structures of a catenane and of a metalio-catenate are reported; upon complexation with CuI, there is a ...
Topoisomerases introduce transient DNA breaks to relax supercoiled DNA, remove catenanes and enable chromosome segregation. ...
Even catenanes and molecular knots made up from achiral molecules are chiral.. ...
... catenane and their subsequent deposition onto an electrode surface. ... catenane and their subsequent deposition onto an electrode surface" (2007). TETRAHEDRON. 182. Retrieved from https:// ...
Title: DNA Origami Catenanes Templated by Gold Nanoparticles Authors: Andreas Peil, Pengfei Zhan, Na Liu ...
... catenanes, TETRAHEDRON LETTERS, Vol: 58, Pages: 3226-3229, ISSN: 0040-4039 ...
... catenanes) below the expected thermodynamic equilibrium? Or is it used to precisely fine tune enzymatic conformations during ...
Electrochemically Driven Molecular Machines Based on Transition-Metal Complexed Catenanes and Rotaxanes Electrochemistry of ...
... "catenane". Unlike ordinary chemical bonds, the molecules in catenanes are linked like a chain, and so the links can move ... This work, published in Nature (Self-assembled poly-catenanes from supramolecular toroidal building blocks), reports the ... By altering self-assembly conditions, the group were able to create intricate structures, including a nano-[5]catenane with ... catenanes with up to 22 rings. Given the scale of these structures (already hundreds of nanometres), it is likely that only ...
... cut the resulting Möbius shapes along their length to produce twisted ring structures and interlocking loops known as catenanes ...
... called a catenane. Normally, molecules are joined by strong covalent bonds in which the atoms share electrons, but in the chain ...
Kinetic Monte Carlo modelling of interlocked catenane formation. Datta, A., Das, A. & Leherte, L. ...
... catenanes) to date and the introduction of molecular weaving. ... catenanes and knots, and the first molecular weaving (2020). ...
Switchable Reconfiguration of a Seven-Ring Interlocked DNA Catenane Nanostructure. Nano Lett. 2015, 15, 7133-7137. (Link) ...
Catenanes - Preferred Concept UI. M0443666. Scope note. Complex compounds where two cyclic molecules are interlaced together as ...
Title: Effects of linking topology on the shear response of connected ring polymers: Catenanes and bonded rings flow ...
  • Catenanes have been synthesised in two different ways: statistical synthesis and template-directed synthesis. (wikipedia.org)
  • There are two primary approaches to the organic synthesis of catenanes. (wikipedia.org)
  • There are a number of distinct methods of holding the precursors together prior to the ultimate ring-closing reaction in a template-directed catenane synthesis. (wikipedia.org)
  • Synthesis and Characterization of Poly[2]-catenanes Containing Rigid Catenane Segments. (mpg.de)
  • Poly[2]catenanes and Cyclic Oligo[2]catenanes Containing Alternating Topological and Covalent Bonds: Synthesis and Characterization. (mpg.de)
  • This work, published in Nature ( 'Self-assembled poly-catenanes from supramolecular toroidal building blocks' ), reports the first template-free synthesis of nano-poly[n]catenanes via molecular self-assembly. (nanowerk.com)
  • Dr. Leigh will discuss the latest progress from his laboratory, including the synthesis of some of the most complex molecular knots and links (catenanes) to date and the introduction of molecular weaving. (gonzaga.edu)
  • n After the synthesis of the 3D-catenane, the author\u0027s interest shifted towards systems which are challenging as well as functional. (soken.ac.jp)
  • Catenanes, as the name of Latin origin suggests (catena = chain), are chain-like molecules composed of at least two cyclic compounds (i.e., a [2]catenane) that are not covalently linked to one another but nevertheless cannot be separated unless covalent bond breakage occurs. (rf-onlinegame.com)
  • Catenanes, or topologically linked circular molecules, were first extracted from living cells by Vinograd and co-workers (1,2). (rf-onlinegame.com)
  • Unlike ordinary chemical bonds, the molecules in catenanes are linked like a chain, and so the links can move relative to each other. (nanowerk.com)
  • The first step towards a molecular machine was taken by Jean-Pierre Sauvage in 1983, when he succeeded in linking two ring-shaped molecules together to form a chain, called a catenane . (nobelprize.org)
  • In view of synthetic challenge, the author has studied the construction of topologically complex, interlocked molecules (catenanes) by self-assembly. (soken.ac.jp)
  • In macromolecular chemistry, a catenane (from Latin catena 'chain') is a mechanically interlocked molecular architecture consisting of two or more interlocked macrocycles, i.e. a molecule containing two or more intertwined rings. (wikipedia.org)
  • When molecular recognition motifs exist in the finished catenane (usually those that were used to synthesize the catenane), the catenane can have one or more thermodynamically preferred positions of the rings with respect to each other (recognition sites). (wikipedia.org)
  • In this article, we use 1 H NMR spectroscopy to study the spontaneous molecular motion of donor-acceptor [2]catenanes in water. (bath.ac.uk)
  • Landmark achievements of his lab include the first synthetic Brownian ratchet molecular motors (2003), synthetic molecular machines able to perform macroscopic work (2005), the invention of catalytic routes to rotaxanes, catenanes and knots, and the first molecular weaving (2020). (gonzaga.edu)
  • A twisted triple trefoil tangle 1 and a molecular granny knot 2 have been made by catenane wizard David Leigh and his team from the University of Manchester, UK. (chemistryworld.com)
  • El Máster en Nanociencia y Nanotecnología Molecular responde al perfil académico e investigador a través de una oferta de asignaturas en áreas científicas y tecnológicas de interés actual como son la Electrónica Molecular, el Nanomagnetismo y la Espintrónica Molecular, la Química Supramolecular, la Física de Superficies, o la Ciencia de los Materiales Moleculares. (uclm.es)
  • Que los estudiantes de un área de conocimiento (p.e. física) sean capaces de comunicarse e interaccionar científicamente con colegas de otras áreas de conocimiento (p.e. química en la resolución de problemas planteados por la Nanociencia y la Nanotecnología Molecular. (uclm.es)
  • Conocer los fundamentos de física del estado sólido y de química supramolecular necesarios en nanociencia molecular. (uclm.es)
  • Is ATP-hydrolysis needed to ensure topology simplification by keeping the number of complex DNA topoisomers (e.g. knots, catenanes) below the expected thermodynamic equilibrium? (jic.ac.uk)
  • Self-assembled poly-catenanes from supramolecular toroidal building blocks. (supsi.ch)
  • Recently the terminology "mechanical bond" has been coined that describes the connection between the macrocycles of a catenane. (wikipedia.org)
  • The approach also provides information on the affinity constants between different macrocycles thanks to the equilibrium between the individual components and the catenanes, allowing a titration-like experiment. (wikipedia.org)
  • When a catenane is synthesized by coordination of the macrocycles around a metal ion, then removal and re-insertion of the metal ion can switch the free motion of the rings on and off. (wikipedia.org)
  • Another family of catenanes are called pretzelanes or bridged [2]catenanes after their likeness to pretzels with a spacer linking the two macrocycles. (wikipedia.org)
  • n]Rotaxanes (Figure1A) are composed of a central dumbbell-shaped component encircled by nÀ1 trapped rings, while [n]catenanes (Figure 1B) contain n interlocked macrocycles. (rf-onlinegame.com)
  • The efficient synthetic methodologies obtaining [2] catenane by interlocking two macrocycles have been recently established. (soken.ac.jp)
  • However, construction of their three-dimensional analog which is also a [2] catenane but composed of two macrobicyclic three-dimensional cages instead of two macrocycles has never been achieved. (soken.ac.jp)
  • Described in Chapter 4 is the construction of [2] catenane composed of Zn(II) and Au(III) porphyrin-incorporated macrocycles which is capable of intramolecular photo induced electron transfer between donor and acceptor components. (soken.ac.jp)
  • even if a macrocycle closes without forming a catenane it can re-open and yield the desired interlocked structure later. (wikipedia.org)
  • By altering self-assembly conditions, the group were able to create intricate structures, including a nano-[5]catenane with interlocked rings in a linear arrangement, which has been named "nanolympiadane" in homage to the [5]catenane system "olympiadane" first reported by Fraser Stoddart and colleagues in 1994, and the well-known symbol of the Olympic games. (nanowerk.com)
  • The team used a versatile construction method known as DNA origami and in a dramatic extension of the technique, (which they refer to as DNA Kirigami), they cut the resulting Möbius shapes along their length to produce twisted ring structures and interlocking loops known as catenanes. (foresight.org)
  • Informed by the step-wise nature of the formation mechanism, they added monomers sequentially, and were thereby able to create poly[n]catenanes with up to 22 rings. (nanowerk.com)
  • Motion is controlled by the size of the catenane rings and the arrangement of the electron-deficient and electron-rich aromatic units. (bath.ac.uk)
  • The first is to simply perform a ring-closing reaction with the hope that some of the rings will form around other rings giving the desired catenane product. (wikipedia.org)
  • A particularly interesting property of many catenanes is the ability of the rings to rotate with respect to one another. (wikipedia.org)
  • Catenanes are two interlocked cycles, like two links in a chain, which cannot be separated without the breaking of a covalent bond. (rf-onlinegame.com)
  • More recently, the groups of Sanders and Otto have shown that dynamic combinatorial approaches using reversible chemistry can be particularly successful in preparing new catenanes of unpredictable structure. (wikipedia.org)
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  • These non-covalent interactions offset some of the entropic cost of association and help position the components to form the desired catenane upon the final ring-closing. (wikipedia.org)
  • The majority of the chemical systems discussed here are based on pseudorotaxanes and catenanes. (unibo.it)
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  • Each noncovalent approach to catenane formation results in what can be considered different families of catenanes. (wikipedia.org)
  • Introduction of [2]Catenanes into Langmuir Films and Langmuir-Blodgett Multilayers. (mpg.de)
  • Thus a novel system was designed where porphyrin array is incorporated into a catenane structure. (soken.ac.jp)
  • He synthesized a porphyrin catenane that constitutes multi-component, photo-induced electron transfer system where components are assembled and arrayed through catenation. (soken.ac.jp)
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  • As a consequence of their interlocked structure, catenanes and rotaxanes may present such a 3D scaffold, and can be chiral by inclusion of a classical chiral element and/or as a consequence of the mechanical bond. (lancs.ac.uk)
  • This Minireview presents illustrative examples of chiral [2]catenanes and [2]rotaxanes, and discusses where these molecules have been used in chemical applications such as chiral host-guest recognition and asymmetric catalysis. (lancs.ac.uk)
  • Strategies and tactics for the metal-directed synthesis of rotaxanes, knots, catenanes, and higher order links. (typeset.io)
  • Catenanes, rotaxanes, knots and Borromean rings have all been successfully accessed by methods in which metal ions play a pivotal role. (typeset.io)
  • Rikke has developed methods for the production and characterisation of catenanes and rotaxanes. (sdu.dk)
  • In addition to host-guest chemistry, the favourable binding of CDs to common organic scaffolds has also made CDs popular building blocks for the construction of complex molecular topology such as rotaxanes and catenanes [12-15] . (beilstein-journals.org)
  • Catenanes have been synthesized incorporating many functional units, including redox-active groups (e.g. viologen, TTF=tetrathiafulvalene), photoisomerizable groups (e.g. azobenzene), fluorescent groups and chiral groups. (wikipedia.org)
  • In addition, any pre-catenanes are mechanically transformed into catenanes9. (rxcostore.com)
  • By exploiting the ability of the calixarene to thread appropriate non-symmetric axles with directional selectivity, we assembled an oriented pseudorotaxane and converted it into the corresponding oriented catenane by intramolecular ring closing metathesis. (unibo.it)
  • All the results indicate that the [2]catenane is thermodynamically the most stable structure, while the [3]catanane is a meta-stable self-assembly. (typeset.io)
  • The reversible redox-switching of the bistable [2]catenanes is retained inside the MOF, as evidenced by solid-state UV-vis-NIR reflectance spectroscopy and cyclic voltammetry. (bgu.ac.il)
  • An anion templated double cyclization strategy to synthesize [2]catenanes in which two identical acyclic pyridinium receptor motifs interweave around a chloride anion template is described. (kent.ac.uk)
  • This "template-directed" approach, together with the use of high-pressure conditions, can provide yields of over 90%, thus improving the potential of catenanes for applications. (wikipedia.org)
  • Ring closing metathesis (RCM) of the preorganized orthogonal precursor chloride complex facilitates the isolation of [2]catenanes in very high yields. (kent.ac.uk)
  • More recently, the groups of Sanders and Otto have shown that dynamic combinatorial approaches using reversible chemistry can be particularly successful in preparing new catenanes of unpredictable structure. (wikipedia.org)
  • If there are more than one recognition sites it is possible to observe different colors depending on the recognition site the ring occupies and thus it is possible to change the color of the catenane solution by changing the preferred recognition site. (wikipedia.org)
  • The approach also provides information on the affinity constants between different macrocycles thanks to the equilibrium between the individual components and the catenanes, allowing a titration-like experiment. (wikipedia.org)
  • DOSY study on dynamic catenation: self-assembly of a [3]catenane as a meta-stable compound from twelve simple components. (typeset.io)
  • CSI-MS studies further support the assigned catenane super structures 6 and 7. (typeset.io)
  • Each noncovalent approach to catenane formation results in what can be considered different families of catenanes. (wikipedia.org)
  • He has also synthesised catenanes and metal-containing polymers by dynamic ring opening polymerisation. (royalsociety.org)
  • 1H NMR anion binding investigations demonstrate the catenanes to be highly selective hosts for chloride in preference to more basic monocharged oxoanions. (kent.ac.uk)
  • The resolution of catenanes is unlikely to be mechanistically distinct from the unlinking of precatenanes behind replication forks18. (rxcostore.com)
  • May promote the resolution of double-strand DNA catenanes (intertwines) between sister chromatids. (nih.gov)