|
Development Of Dipeptidyl Peptidase-4 Inhibitors
Dipeptidyl peptidase-4 inhibitors (DPP-4 inhibitors) are enzyme inhibitors that inhibit the enzyme dipeptidyl peptidase-4 (DPP-4). They are used in the treatment of type 2 diabetes mellitus. Inhibition of the DPP-4 enzyme prolongs and enhances the activity of incretins that play an important role in insulin secretion and blood glucose control regulation. Type 2 diabetes mellitus is a chronic metabolic disease that results from inability of the β-cells in the pancreas to secrete sufficient amounts of insulin to meet the body's needs. Insulin resistance and increased hepatic glucose production can also play a role by increasing the body's demand for insulin. Current treatments, other than insulin supplementation, are sometimes not sufficient to achieve control and may cause undesirable side effects, such as weight gain and hypoglycemia. In recent years, new drugs have been developed, based on continuing research into the mechanism of insulin production and regulation of the metaboli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipeptidyl Peptidase-4 Inhibitors
Inhibitors of dipeptidyl peptidase 4 (DPP-4 inhibitors or gliptins) are a class of oral hypoglycemics that block the enzyme dipeptidyl peptidase-4 (DPP-4). They can be used to treat diabetes mellitus type 2. The first agent of the class – sitagliptin – was approved by the FDA in 2006. Glucagon increases blood glucose levels, and DPP-4 inhibitors reduce glucagon and blood glucose levels. The mechanism of DPP-4 inhibitors is to increase incretin levels (GLP-1 and GIP), which inhibit glucagon release, which in turn increases insulin secretion, decreases gastric emptying, and decreases blood glucose levels. A 2018 meta-analysis found no favorable effect of DPP-4 inhibitors on all-cause mortality, cardiovascular mortality, myocardial infarction or stroke in patients with type 2 diabetes. Examples Drugs belonging to this class are: * Sitagliptin (FDA approved 2006, marketed by Merck & Co. as Januvia) * Vildagliptin (EU approved 2007, marketed in the EU by Novartis as Galvus) * S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substrate (biochemistry)
In chemistry, the term substrate is highly context-dependent. Broadly speaking, it can refer either to a chemical species being observed in a chemical reaction, or to a surface on which other chemical reactions or microscopy are performed. In the former sense, a reagent is added to the ''substrate'' to generate a product through a chemical reaction. The term is used in a similar sense in synthetic and organic chemistry, where the substrate is the chemical of interest that is being modified. In biochemistry, an enzyme substrate is the material upon which an enzyme acts. When referring to Le Chatelier's principle, the substrate is the reagent whose concentration is changed. ;Spontaneous reaction : :*Where S is substrate and P is product. ;Catalysed reaction : :*Where S is substrate, P is product and C is catalyst. In the latter sense, it may refer to a surface on which other chemical reactions are performed or play a supporting role in a variety of spectroscopic and microscop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphonate
In organic chemistry, phosphonates or phosphonic acids are organophosphorus compounds containing groups (where R = alkyl, aryl, or just hydrogen). Phosphonic acids, typically handled as salts, are generally nonvolatile solids that are poorly soluble in organic solvents, but soluble in water and common alcohols. Many commercially important compounds are phosphonates, including glyphosate (the active molecule of the herbicide Roundup), and ethephon, a widely used plant growth regulator. Bisphosphonates are popular drugs for treatment of osteoporosis.Svara, J.; Weferling, N.; Hofmann, T. "Phosphorus Compounds, Organic," in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim, 2008. . In biochemistry and medicinal chemistry, phosphonate groups are used as stable bioisoteres for phosphate, such as in the antiviral nucleotide analog, Tenofovir, one of the cornerstones of anti-HIV therapy. And there is an indication that phosphonate derivatives are "promising ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boronic Acids
A boronic acid is an organic compound related to boric acid () in which one of the three hydroxyl groups () is replaced by an alkyl or aryl group (represented by R in the general formula ). As a compound containing a carbon–boron bond, members of this class thus belong to the larger class of organoboranes. Boronic acids act as Lewis acids. Their unique feature is that they are capable of forming reversible covalent complexes with sugars, amino acids, hydroxamic acids, etc. (molecules with vicinal, (1,2) or occasionally (1,3) substituted Lewis base donors (alcohol, amine, carboxylate)). The p''K''a of a boronic acid is ~9, but they can form tetrahedral boronate complexes with p''K''a ~7. They are occasionally used in the area of molecular recognition to bind to saccharides for fluorescent detection or selective transport of saccharides across membranes. Boronic acids are used extensively in organic chemistry as chemical building blocks and intermediates predominantly in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serine
Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − form under biological conditions), and a side chain consisting of a hydroxymethyl group, classifying it as a polar amino acid. It can be synthesized in the human body under normal physiological circumstances, making it a nonessential amino acid. It is encoded by the codons UCU, UCC, UCA, UCG, AGU and AGC. Occurrence This compound is one of the naturally occurring proteinogenic amino acids. Only the L-stereoisomer appears naturally in proteins. It is not essential to the human diet, since it is synthesized in the body from other metabolites, including glycine. Serine was first obtained from silk protein, a particularly rich source, in 1865 by Emil Cramer. Its name is derived from the Latin for silk, ''sericum''. Serine's structure was estab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imidate
Carboximidates (or more general imidates) are organic compounds, which can be thought of as esters formed between a carboximidic acid (R-C(=NR')OH) and an alcohol, with the general formula R-C(=NR')OR". They are also known as imino ethers, since they resemble imines (>C=N-) with an oxygen atom connected to the carbon atom of the C=N double bond. Synthesis Imidates may be generated by a number of synthetic routes, but are in general formed by the Pinner reaction. This proceeds via the acid catalyzed attack of nitriles by alcohols. Imidates produced in this manner are formed as their hydrochloride salts, which are sometimes referred to as Pinner salts. Carboximidates are also formed as intermediates in the Mumm rearrangement and the Overman rearrangement. Imidate/amidate anions An amidate/imidate anion is formed upon deprotonation of an amide or imidic acid. Since amides and imidic acids are tautomers, they form the same anion upon deprotonation. The two names are thus syn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Function Group
In organic chemistry, a functional group is a substituent or moiety in a molecule that causes the molecule's characteristic chemical reactions. The same functional group will undergo the same or similar chemical reactions regardless of the rest of the molecule's composition. This enables systematic prediction of chemical reactions and behavior of chemical compounds and the design of chemical synthesis. The reactivity of a functional group can be modified by other functional groups nearby. Functional group interconversion can be used in retrosynthetic analysis to plan organic synthesis. A functional group is a group of atoms in a molecule with distinctive chemical properties, regardless of the other atoms in the molecule. The atoms in a functional group are linked to each other and to the rest of the molecule by covalent bonds. For repeating units of polymers, functional groups attach to their nonpolar core of carbon atoms and thus add chemical character to carbon chains. Fu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrile
In organic chemistry, a nitrile is any organic compound that has a functional group. The prefix ''cyano-'' is used interchangeably with the term ''nitrile'' in industrial literature. Nitriles are found in many useful compounds, including methyl cyanoacrylate, used in super glue, and nitrile rubber, a nitrile-containing polymer used in latex-free laboratory and medical gloves. Nitrile rubber is also widely used as automotive and other seals since it is resistant to fuels and oils. Organic compounds containing multiple nitrile groups are known as cyanocarbons. Inorganic compounds containing the group are not called nitriles, but cyanides instead. Though both nitriles and cyanides can be derived from cyanide salts, most nitriles are not nearly as toxic. Structure and basic properties The N−C−C geometry is linear in nitriles, reflecting the sp hybridization of the triply bonded carbon. The C−N distance is short at 1.16 Å, consistent with a triple bond. Nitriles a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalytic
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some stag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiazolidine
Thiazolidine is a heterocyclic organic compound with the formula (CH2)3(NH)S. It is a 5-membered saturated ring with a thioether group and an amine group in the 1 and 3 positions. It is a sulfur analog of oxazolidine. Thiazolidine is a colorless liquid. Derivatives, thiazolidines, are known. For example, the drug pioglitazone contains a thiazolidine ring. Another drug that contains a thiazolidine ring is the antibiotic penicillin. Preparation Thiazolidine is prepared as it was in its first reported synthesis, by the condensation of cysteamine and formaldehyde. Other thiazolidines may be synthesized by similar condensations. A notable derivative is 4-carboxythiazolidine, derived from formaldehyde and cysteine. Derivatives N-Methyl-2-thiazolidinethione is an accelerator for the vulcanization of chloroprene rubbers. Thiazolidines functionalized with carbonyls at the 2 and 4 positions, the thiazolidinediones, are drugs used in the treatment of diabetes mellitus type 2. Rhodanin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrrolidine
Pyrrolidine, also known as tetrahydropyrrole, is an organic compound with the molecular formula (CH2)4NH. It is a cyclic secondary amine, also classified as a saturated heterocycle. It is a colourless liquid that is miscible with water and most organic solvents. It has a characteristic odor that has been described as "ammoniacal, fishy, shellfish-like". In addition to pyrrolidine itself, many substituted pyrrolidines are known. Production and synthesis Industrial production Pyrrolidine is prepared industrially by the reaction of 1,4-butanediol and ammonia at a temperature of 165–200 °C and a pressure of 17–21 MPa in the presence of a cobalt- and nickel oxide catalyst, which is supported on alumina. : The reaction is carried out in the liquid phase in a continuous tube- or tube bundle reactor, which is operated in the cycle gas method. The catalyst is arranged as a fixed-bed and the conversion is carried out in the downflow mode. The product is obtained after mu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mimic
MIMIC, known in capitalized form only, is a former simulation computer language developed 1964 by H. E. Petersen, F. J. Sansom and L. M. Warshawsky of Systems Engineering Group within the Air Force Materiel Command at the Wright-Patterson AFB in Dayton, Ohio, United States. It is an expression-oriented continuous block simulation language, but capable of incorporating blocks of FORTRAN-like algebra. MIMIC is a further development from MIDAS (Modified Integration Digital Analog Simulator), which represented analog computer design. Written completely in FORTRAN but one routine in COMPASS, and ran on Control Data supercomputers, MIMIC is capable of solving much larger simulation models. With MIMIC, ordinary differential equations describing mathematical models in several scientific disciplines as in engineering, physics, chemistry, biology, economics and as well as in social sciences can easily be solved by numerical integration and the results of the analysis are listed or drawn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
