|
α-Cyclodextrin
α-Cyclodextrin (''alpha''-cyclodextrin), sometimes abbreviated as α-CD, is a hexasaccharide derived from glucose. It is related to the β- (beta) and γ- (gamma) cyclodextrins, which contain seven and eight glucose units, respectively. All cyclodextrins are white, water-soluble solids with minimal toxicity. Cyclodextrins tend to bind other molecules in their quasi-cylindrical, lipophilic interiors. The compound is of wide interest because it exhibits host–guest properties, forming inclusion compounds. This inclusion (and release) behavior leads to applications in medicine. Structure In α-cyclodextrin, the six glucose subunits are linked end to end via α-1, 4 linkages. The result has the shape of a tapered cylinder, with six primary alcohols on one face and twelve secondary alcohol groups on the other. The exterior surface of cyclodextrins is somewhat hydrophilic whereas the interior core is hydrophobic. Applications α-Cyclodextrin is marketed for a range of medical, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclodextrin
Cyclodextrins are a family of cyclic oligosaccharides, consisting of a macrocycle, macrocyclic ring of glucose subunits joined by α-1,4 glycosidic bonds. Cyclodextrins are produced from starch by enzyme, enzymatic conversion. They are used in food, pharmaceutical, drug delivery, and chemical industries, as well as agriculture and environmental engineering. Cyclodextrins are composed of 5 or more α-D-glucoPyranose, pyranoside units linked 1 → 4, as in amylose (a fragment of starch). Typical cyclodextrins contain a number of glucose monomers ranging from six to eight units in a ring, creating a cone shape: * α-Cyclodextrin, α (alpha)-cyclodextrin: 6 glucose subunits * β-Cyclodextrin, β (beta)-cyclodextrin: 7 glucose subunits * γ-Cyclodextrin, γ (gamma)-cyclodextrin: 8 glucose subunits The largest well-characterized cyclodextrin contains 32 1,4-anhydroglucopyranoside units. Poorly-characterized mixtures, containing at least 150-membered cyclic oligosaccharides are also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
β-Cyclodextrin
β-Cyclodextrin sometimes abbreviated as β-CD, is a heptasaccharide derived from glucose. The α- (alpha), β- (beta), and γ- (gamma) cyclodextrins correspond to six, seven, and eight glucose units, respectively. β-Cyclodextrin is the most used natural cyclodextrin in marketed medicines. The reason for this lies in the ease of its production and subsequent low price (more than 10,000 tons produced annually with an average bulk price of approximately 5 USD per kg). Structure In β-cyclodextrin, the seven glucose subunits are linked end to end via α-1,4 linkages. The result has the shape of a tapered cylinder, with seven primary alcohols on one face and fourteen secondary alcohol groups on the other. The exterior surface of cyclodextrins is somewhat hydrophilic whereas the interior core is hydrophobic. Physical properties β-Cyclodextrin exists as a white (colorless) powder or crystals. The density of its saturated hydrate crystal (βCD·12H2O) is 1.46 g/cm3. β-Cyclodextrin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
γ-Cyclodextrin
γ-Cyclodextrin sometimes abbreviated as γ-CD, is an octa saccharide derived from glucose Glucose is a sugar with the Chemical formula#Molecular formula, molecular formula , which is often abbreviated as Glc. It is overall the most abundant monosaccharide, a subcategory of carbohydrates. It is mainly made by plants and most algae d .... The α- (alpha), β- (beta), and γ- (gamma) cyclodextrins correspond to six, seven, and eight glucose units, respectively. Structure In γ-cyclodextrin, the eight glucose subunits are linked end to end via α-1,4 linkages. The result has the shape of a tapered cylinder, with 8 primary alcohols on one face and 16 secondary alcohol groups on the other. The exterior surface of cyclodextrins is somewhat hydrophilic whereas the interior core is hydrophobic. Physical properties γ-Cyclodextrin exists as a white (colorless) powder or crystals. The density of its hydrate crystal (γCD·14H2O) is 1.41 g/cm3. γ-Cyclodextrin is well soluble in wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccharide
A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' may differ). This formula does not imply direct covalent bonding between hydrogen and oxygen atoms; for example, in , hydrogen is covalently bonded to carbon, not oxygen. While the 2:1 hydrogen-to-oxygen ratio is characteristic of many carbohydrates, exceptions exist. For instance, uronic acids and deoxy-sugars like fucose deviate from this precise stoichiometric definition. Conversely, some compounds conforming to this definition, such as formaldehyde and acetic acid, are not classified as carbohydrates. The term is predominantly used in biochemistry, functioning as a synonym for saccharide (), a group that includes sugars, starch, and cellulose. The saccharides are divided into four chemical groups: monosaccharides, disaccharides, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucose
Glucose is a sugar with the Chemical formula#Molecular formula, molecular formula , which is often abbreviated as Glc. It is overall the most abundant monosaccharide, a subcategory of carbohydrates. It is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using energy from sunlight. It is used by plants to make cellulose, the most abundant carbohydrate in the world, for use in cell walls, and by all living Organism, organisms to make adenosine triphosphate (ATP), which is used by the cell as energy. In energy metabolism, glucose is the most important source of energy in all organisms. Glucose for metabolism is stored as a polymer, in plants mainly as amylose and amylopectin, and in animals as glycogen. Glucose circulates in the blood of animals as blood sugar. The naturally occurring form is -glucose, while its Stereoisomerism, stereoisomer L-glucose, -glucose is produced synthetically in comparatively small amounts and is less biologicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inclusion Compound
Inclusion or Include may refer to: Sociology * Social inclusion, action taken to support people of different backgrounds sharing life together. ** Inclusion (disability rights), promotion of people with disabilities sharing various aspects of life and life as a whole with those without disabilities. ** Inclusion (education), to do with students with special educational needs spending most or all of their time with non-disabled students Science and technology * Inclusion (mineral), any material that is trapped inside a mineral during its formation * Inclusion bodies, aggregates of stainable substances in biological cells * Inclusion (cell), insoluble non-living substance suspended in a cell's cytoplasm * Inclusion (taxonomy), combining of biological species * Include directive, in computer programming Mathematics * Inclusion (set theory), or subset * Inclusion (Boolean algebra), the Boolean analogue to the subset relation * Inclusion map, or inclusion function, or canonical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotaxane Crystal Structure ChemComm Page493 2001 Commons
A rotaxane () is a mechanically interlocked molecular architecture consisting of a dumbbell-shaped molecule which is threaded through a macrocycle (see graphical representation). The two components of a rotaxane are kinetically trapped since the ends of the dumbbell (often called ''stoppers'') are larger than the internal diameter of the ring and prevent dissociation (unthreading) of the components since this would require significant distortion of the covalent bonds. Much of the research concerning rotaxanes and other mechanically interlocked molecular architectures, such as catenanes, has been focused on their efficient synthesis or their utilization as artificial molecular machines. However, examples of rotaxane substructure have been found in naturally occurring peptides, including: cystine knot peptides, cyclotides or lasso-peptides such as microcin J25. Synthesis The earliest reported synthesis of a rotaxane in 1967 relied on the statistical probability that if t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclodextrin Glycosyltransferase
In enzymology, a cyclomaltodextrin glucanotransferase (also cyclodextrin glycosyl transferase or CGTase for short) () is an enzyme that catalyzes the chemical reaction of cyclizing part of a 1,4-alpha-D- glucan molecule through the formation of a 1,4-alpha-D-glucosidic bond. They are bacterial enzymes belonging to the same family of the α-amylase specifically known as glycosyl-hydrolase family 13. This peculiar enzyme is capable of catalyzing more than one reaction with the most important being the synthesis of non-reducing cyclic dextrins known as cyclodextrins starting from starch, amylose, and other polysaccharides. CGTase is an enzyme common to many bacterial species, in particular of the ''Bacillus'' genus (e.g. ''B. circulans'', ''B. macerans'' and ''B. stearothermophilus'') and ''Brevibacillus brevis.'' This enzyme belongs to the family of glycosyltransferases, specifically the hexosyltransferases. The systematic name A systematic name is a name given in a systema ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligosaccharides
An oligosaccharide (; ) is a saccharide polymer containing a small number (typically three to ten) of monosaccharides (simple sugars). Oligosaccharides can have many functions including cell recognition and cell adhesion. They are normally present as glycans: oligosaccharide chains are linked to lipids or to compatible amino acid side chains in proteins, by ''N''- or ''O''- glycosidic bonds. ''N''-Linked oligosaccharides are always pentasaccharides attached to asparagine via a beta linkage to the amine nitrogen of the side chain.. Alternately, ''O''-linked oligosaccharides are generally attached to threonine or serine on the alcohol group of the side chain. Not all natural oligosaccharides occur as components of glycoproteins or glycolipids. Some, such as the raffinose series, occur as storage or transport carbohydrates in plants. Others, such as maltodextrins or cellodextrins, result from the microbial breakdown of larger polysaccharides such as starch or cellulose. Gly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
