|
Racemic Drug
Chemical compounds that come as mirror-image pairs are referred to by chemists as chiral or handed molecules. Each twin is called an enantiomer. Drugs that exhibit handedness are referred to as chiral drugs. Chiral drugs that are equimolar (1:1) mixture of enantiomers are called racemic drugs and these are obviously devoid of optical rotation. The most commonly encountered stereogenic unit, that confers chirality to drug molecules are stereogenic center. Stereogenic center can be due to the presence of tetrahedral tetra coordinate atoms (C,N,P) and pyramidal tricoordinate atoms (N,S). The word chiral describes the three-dimensional architecture of the molecule and does not reveal the stereochemical composition. Hence "chiral drug" does not say whether the drug is racemic (racemic drug), single enantiomer (chiral specific drug) or some other combination of stereoisomers. To resolve this issue ''Joseph Gal'' introduced a new term called '' unichiral.'' Unichiral indicates that the ster ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirality (chemistry)
In chemistry, a molecule or ion is called chiral () if it cannot be superposed on its mirror image by any combination of rotation (geometry), rotations, translation (geometry), translations, and some Conformational isomerism, conformational changes. This geometric property is called chirality (). The terms are derived from Ancient Greek (''cheir'') 'hand'; which is the canonical example of an object with this property. A chiral molecule or ion exists in two stereoisomers that are mirror images of each other, called enantiomers; they are often distinguished as either "right-handed" or "left-handed" by their absolute configuration or some other criterion. The two enantiomers have the same chemical properties, except when reacting with other chiral compounds. They also have the same physics, physical properties, except that they often have opposite optical activity, optical activities. A homogeneous mixture of the two enantiomers in equal parts is said to be racemic mixture, racem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dopa Enantiomers in Thailand
{{Disambiguation ...
Dopa or DOPA may refer to: * Dihydroxyphenylalanine (DOPA) ** L-DOPA (levodopa), used in the treatment of Parkinson's disease ** D-DOPA, an enantiomer of L-DOPA * 3,4-Dihydroxyphenylacetic acid or DOPAC, a metabolite of dopamine * Dopa, an angel in Enochian * Deleting Online Predators Act of 2006 * Department of Provincial Administration (DOPA), a department under the Ministry of Interior An interior ministry or ministry of the interior (also called ministry of home affairs or ministry of internal affairs) is a government department that is responsible for domestic policy, public security and law enforcement. In some states, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketamine Enantiomers
Ketamine is a cyclohexanone-derived general anesthetic and NMDA receptor antagonist with analgesic and hallucinogenic properties, used medically for anesthesia, depression, and pain management. Ketamine exists as its S- (esketamine) and R- (arketamine) two enantiomers and has antidepressant action likely involving additional mechanisms than NMDA antagonism. At anesthetic doses, ketamine induces a state of dissociative anesthesia, a trance-like state providing pain relief, sedation, and amnesia. Its distinguishing features as an anesthestic are preserved breathing and airway reflexes, stimulated heart function with increased blood pressure, and moderate bronchodilation. As an anesthetic, it is used especially in trauma, emergency, and pediatric cases. At lower, sub-anesthetic doses, it is used as a treatment for pain and treatment-resistant depression. Ketamine is legally used in medicine but is also tightly controlled due to its potential for recreational use and dissoci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penicillamine
Penicillamine, sold under the brand name of Cuprimine among others, is a medication primarily used for the treatment of Wilson's disease. It is also used for people with kidney stones who have high urine cystine levels, rheumatoid arthritis, and various heavy metal poisonings. It is taken by mouth. Penicillamine was approved for medical use in the United States in 1970. It is on the World Health Organization's List of Essential Medicines. Medical uses It is used as a chelating agent: * In Wilson's disease, a rare genetic disorder of copper metabolism, penicillamine treatment relies on its binding to accumulated copper and elimination through urine. Succimer (dimercaptosuccinic acid) is increasingly used in place of penicillamine. * Penicillamine was the second line treatment for arsenic poisoning, after dimercaprol (BAL). It is no longer recommended. In cystinuria, a hereditary disorder in which high urine cystine levels lead to the formation of cystine stones, penicilla ... [...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] |
Chiral Inversion
Chiral inversion is the process of conversion of one enantiomer of a chiral molecule to its mirror-image version with no other change in the molecule. Chiral inversion happens depending on various factors (viz. biological-, solvent-, light-, temperature- induced, etc.) and the energy barrier energy barrier associated with the stereogenic element present in the chiral molecule. 2-Arylpropionic acid nonsteroidal anti-inflammatory drugs (NSAIDs) provide one of the best pharmaceutical examples of chiral inversion. Chirality is attributed to a molecule due to the presence of a stereogenic element (viz. center, planar, helical, or axis). Many pharmaceutical drugs are chiral and have a labile (configurationally unstable) stereogenic element. Chiral compounds with stereogenic center are found to have high energy barriers for inversion and generally undergo biologically mediated chiral inversion. While compounds with helical or planar chirality have low energy barriers and chiral inver ... [...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] |
Propoxyphene
Dextropropoxyphene is an analgesic in the opioid category, patented in 1955 and manufactured by Eli Lilly and Company. It is an optical isomer of levopropoxyphene. It is intended to treat mild pain and also has antitussive (cough suppressant) and local anaesthetic effects. The drug has been taken off the market in Europe and the US due to concerns of fatal overdoses and heart arrhythmias. It is still available in Australia, albeit with restrictions after an application by its manufacturer to review its proposed banning. Its onset of analgesia (pain relief) is said to be 20–30 minutes and peak effects are seen about 1.5–2.0 hours after oral administration. Dextropropoxyphene is sometimes combined with acetaminophen. Trade names include Darvocet-N, Di-Gesic, and Darvon with APAP (for dextropropoxyphene and paracetamol). The British approved name (i.e. the generic name of the active ingredient) of the paracetamol/dextropropoxyphene preparation is co-proxamol (sold under a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indacrinone
Indacrinone is a loop diuretic. It can be used in patients of gout with hypertension as an antihypertensive because it decreases reabsorption of uric acid, while other diuretics increase it. Chirality and biological activity Indacrinone is a chiral drug, with one chiral center and hence exists as mirror-image twins. (R)-enantiomer, the eutomer, is diuretic whereas the mirror-image version (S)-enantiomer counteracts side effect of the eutomer. Here both the enantiomers contribute to the overall desired effect in different ways. As indicated earlier, the (R)- enantiomer is the pharmacologically active diuretic. Like most other diuretics, the (R)-isomer possesses an undesirable side-effect of retaining uric acid. But the (S)-enantiomer, the distomer The eudysmic ratio (also spelled eudismic ratio) represents the difference in pharmacologic activity between the two enantiomers of a drug. In most cases where a chiral compound is biologically active, one enantiomer is more act ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propranolol
Propranolol is a medication of the beta blocker class. It is used to treat hypertension, high blood pressure, some types of cardiac dysrhythmia, irregular heart rate, thyrotoxicosis, capillary hemangiomas, akathisia, performance anxiety, and essential tremors, as well to prevent migraine headaches, and to prevent further heart problems in those with angina or previous myocardial infarction, heart attacks. It can be taken oral administration, orally or by intravenous injection. The formulation that is taken orally comes in short-acting and long-acting versions. Propranolol appears in the blood after 30 minutes and has a maximum effect between 60 and 90 minutes when taken orally. Common side effects include nausea, abdominal pain, and constipation. It may worsen the symptoms of asthma. Propranolol may cause teratogen, harmful effects for the baby if taken during pregnancy; however, its use during breastfeeding is generally considered to be safe. It is a non-selective beta block ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salbutamol
Salbutamol, also known as albuterol and sold under the brand name Ventolin among others, is a medication that opens up the medium and large airways in the lungs. It is a short-acting β2 adrenergic receptor agonist that causes relaxation of airway smooth muscle. It is used to treat asthma, including asthma attacks and exercise-induced bronchoconstriction, as well as chronic obstructive pulmonary disease (COPD). It may also be used to treat high blood potassium levels. Salbutamol is usually used with an inhaler or nebulizer, but it is also available in a pill, liquid, and intravenous solution. Onset of action of the inhaled version is typically within 15 minutes and lasts for two to six hours. Common side effects include shakiness, headache, fast heart rate, dizziness, and feeling anxious. Serious side effects may include worsening bronchospasm, irregular heartbeat, and low blood potassium levels. It can be used during pregnancy and breastfeeding, but safety is no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
