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Enantiopure Drugs
An enantiopure drug is a pharmaceutical available in one specific enantiomeric form. Most biomolecules (proteins, sugars, etc.) are present in only one of many chiral forms, so different enantiomers of a chiral drug molecule bind differently (or not at all) to target receptors. The use of a drug with a single enantiomer intends to make it more effective. One enantiomer of a drug may have a desired beneficial effect while the other may cause serious and undesired side effects, or sometimes even beneficial but entirely different effects. The desired enantiomer is known as an ''eutomer'' while the undesired enantiomer is known as the ''distomer''. When equal amounts of both enantiomers are found in a mixture, the mixture is known as a racemic mixture. If a mixture for a drug does not have a 1:1 ratio of its enantiomers it is a candidate for an enantiopure drug. Advances in industrial chemical processes have made it economical for pharmaceutical manufacturers to take drugs that wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enantiomer
In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities which are mirror images of each other and non-superposable. Enantiomer molecules are like right and left hands: one cannot be superposed onto the other without first being converted to its mirror image. It is solely a relationship of chirality (chemistry), chirality and the permanent three-dimensional relationships among molecules or other chemical structures: no amount of re-orientation of a molecule as a whole or conformational isomerism, conformational change converts one chemical into its enantiomer. Chemical structures with chirality rotate plane-polarized light. A mixture of equal amounts of each enantiomer, a ''racemic mixture'' or a ''racemate'', does not rotate light. Stereoisomers include both enantiomers and diastereomers. Diaste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the general subject of organic synthesis, there are many different types of synthetic routes that can be completed including total synthesis, Enantioselective synthesis, stereoselective synthesis, automated synthesis, and many more. Additionally, in understanding organic synthesis it is necessary to be familiar with the methodology, techniques, and applications of the subject. Total synthesis A total synthesis refers to the complete chemical synthesis of molecules from simple, Precursor (chemistry), natural precursors. Total synthesis is accomplished either via a linear or convergent approach. In a Linear synthesis, ''linear'' synthesis—often adequate for simple structures—several steps are performed sequentially until the molecule is com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Levamlodipine
Levamlodipine (INN), also known as levoamlodipine or ''S''-amlodipine is a pharmacologically active enantiomer of amlodipine. Amlodipine belongs to the dihydropyridine group of calcium channel blocker used as an antihypertensive and antianginal agent. It was approved by the U.S. FDA in December 2019 and is currently marketed under the brand name Conjupri. Mechanism of action Amlodipine blocks the transmembrane influx of calcium into the vascular and cardiac smooth muscles resulting in vasodilation and hence a fall in blood pressure. Levamlodipine is an allosteric modulator and acts on the L-type of calcium channels. Receptor binding studies have shown that out of the two forms only the (''S'')-enantiomer of amlodipine binds to and blocks L-type calcium channels whereas the (''R'')-enantiomer has no activity on these channels. The precise mechanisms by which levamlodipine relieves angina have not been fully explored, but are thought to include the following: * Decreases peri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amlodipine
Amlodipine, sold under the brand name Norvasc among others, is a calcium channel blocker medication used to treat hypertension, high blood pressure, coronary artery disease (CAD) and variant angina (also called Prinzmetal angina or coronary artery vasospasm, among other names). It is taken Oral administration, orally (swallowed by mouth). Common side effects include edema, swelling, fatigue (medical), feeling tired, abdominal pain, and nausea. Serious side effects may include hypotension, low blood pressure or myocardial infarction, heart attack. Whether use is safe during pregnancy or breastfeeding is unclear. When used by people with liver problems, and in elderly individuals, doses should be reduced. Amlodipine works partly by vasodilation (relaxing the arteries and increasing their diameter). It is a long-acting calcium channel blocker of the dihydropyridine type. Amlodipine was patented in 1982, and approved for medical use in 1990. It is on the WHO Model List of Essent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chiral Switch
A chiral switch is a chiral drug that has already approved as racemate but has been re-developed as a single enantiomer. The term chiral switching was introduced by Agranat and Caner in 1999 to describe the development of single enantiomers from racemate drugs. For example, levofloxacin is a chiral switch of racemic ofloxacin. It is important to understand that chiral switches are treated as a Selection Invention, selection invention. A selection invention is an invention that selects a group of new members from a previously known class on the basis of superior properties. Description The essential principle of a chiral switch is that there is a change in the status of chirality. In general, the term chiral switch is preferred over racemic switch because the switch is usually happening from a racemic drug to the corresponding single enantiomer. To express the pharmacological activities of each of the chiral twins of a racemic drug, two technical terms have been coined: ''eut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclooxygenase-2
Cyclooxygenase-2 (COX-2), also known as prostaglandin-endoperoxide synthase 2 ( HUGO PTGS2), is an enzyme that in humans is encoded by the ''PTGS2'' gene. In humans it is one of three cyclooxygenases. It is involved in the conversion of arachidonic acid to prostaglandin H2, an important precursor of prostacyclin, which is expressed in inflammation. Function PTGS2 (COX-2), converts arachidonic acid (AA) to prostaglandin endoperoxide H2. PTGSs are targets for NSAIDs and PTGS2 (COX-2) specific inhibitors called coxibs. PTGS-2 is a sequence homodimer. Each monomer of the enzyme has a peroxidase and a PTGS (COX) active site. The PTGS (COX) enzymes catalyze the conversion of AA to prostaglandins in two steps. First, hydrogen is abstracted from carbon 13 of arachidonic acid, and then two molecules of oxygen are added by the PTGS2 (COX-2), giving PGG2. Second, PGG2 is reduced to PGH2 in the peroxidase active site. The synthesized PGH2 is converted to prostaglandins ( PGD2, PG ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ibuprofen
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is used to relieve pain, fever, and inflammation. This includes dysmenorrhea, painful menstrual periods, migraines, and rheumatoid arthritis. It can be taken oral administration, orally (by mouth) or Intravenous therapy, intravenously. It typically begins working within an hour. Common side effects include heartburn, nausea, indigestion, and abdominal pain. Potential side effects include gastrointestinal bleeding. Long-term use has been associated with kidney failure, and rarely liver failure, and it can exacerbate the condition of people with heart failure. At low doses, it does not appear to increase the risk of myocardial infarction (heart attack); however, at higher doses it may. Ibuprofen can also worsen asthma. While its safety in early pregnancy is unclear, it appears to be harmful in later pregnancy, so it is not recommended during that period. It works by inhibiting the production of prostaglandins by dec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Generic Drug
A generic drug is a pharmaceutical drug that contains the same chemical substance as a drug that was originally protected by chemical patents. Generic drugs are allowed for sale after the patents on the original drugs expire. Because the active chemical substance is the same, the medical profile of generics is equivalent in performance compared to their performance at the time when they were patented drugs. A generic drug has the same active pharmaceutical ingredient (API) as the original, but it may differ in some characteristics such as the manufacturing process, formulation, excipients, color, taste, and packaging. Although they may not be associated with a particular company, generic drugs are usually subject to government regulations in the countries in which they are dispensed. They are labeled with the name of the manufacturer and a generic non-proprietary name such as the United States Adopted Name (USAN) or International Nonproprietary Name (INN) of the drug. A generic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binding Site
In biochemistry and molecular biology, a binding site is a region on a macromolecule such as a protein that binds to another molecule with specificity. The binding partner of the macromolecule is often referred to as a ligand. Ligands may include other proteins (resulting in a protein–protein interaction), enzyme substrates, second messengers, hormones, or allosteric modulators. The binding event is often, but not always, accompanied by a conformational change that alters the protein's function. Binding to protein binding sites is most often reversible (transient and non-covalent), but can also be covalent reversible or irreversible. Function Binding of a ligand to a binding site on protein often triggers a change in conformation in the protein and results in altered cellular function. Hence binding site on protein are critical parts of signal transduction pathways. Types of ligands include neurotransmitters, toxins, neuropeptides, and steroid hormones. Binding site ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recrystallization (chemistry)
Recrystallization is a broad class of List of purification methods in chemistry , chemical purification techniques characterized by the dissolution of an impure sample in a solvent or solvent mixture, followed by some change in conditions that encourages the formation of pure isolate as solid crystals. Recrystallization as a purification technique is driven by spontaneous process , spontaneous processes of molecular self-assembly , self-assembly that leverage the highly ordered (i.e. low-entropy) and periodic characteristics of a crystal's molecular structure to produce purification. Basic principles The driving force of this purification emerges from the difference in molecular interactions between the isolate and the impurities: if a molecule of the desired isolate interacts with any isolate crystal present, it is likely the molecule Deposition (chemistry) , deposits on the crystal's ordered surface and contributes to the crystal's growth; if a molecule of the impurity inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromatography
In chemical analysis, chromatography is a laboratory technique for the Separation process, separation of a mixture into its components. The mixture is dissolved in a fluid solvent (gas or liquid) called the ''mobile phase'', which carries it through a system (a column, a capillary tube, a plate, or a sheet) on which a material called the ''stationary phase'' is fixed. Because the different constituents of the mixture tend to have different affinities for the stationary phase and are retained for different lengths of time depending on their interactions with its surface sites, the constituents travel at different apparent velocities in the mobile fluid, causing them to separate. The separation is based on the differential partitioning between the mobile and the stationary phases. Subtle differences in a compound's partition coefficient result in differential retention on the stationary phase and thus affect the separation. Chromatography may be ''preparative'' or ''analytical' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NMR Shift
Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique based on re-orientation of atomic nuclei with non-zero nuclear spins in an external magnetic field. This re-orientation occurs with absorption of electromagnetic radiation in the radio frequency region from roughly 4 to 900 MHz, which depends on the isotopic nature of the nucleus and increases proportionally to the strength of the external magnetic field. Notably, the resonance frequency of each NMR-active nucleus depends on its chemical environment. As a result, NMR spectra provide information about individual functional groups present in the sample, as well as about connections between nearby nuclei in the same molecule. As the NMR spectra are unique or highly characteristic to individual compounds and functional groups, NMR spectroscopy is one of the most important methods to identify molecular structures, particularly of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
