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Mephenytoin
Mephenytoin (marketed as Mesantoin by Novartis) is a hydantoin, used as an anticonvulsant. It was introduced approximately 10 years after phenytoin, in the late 1940s. The significant metabolite of mephenytoin is nirvanol (5-ethyl-5-phenylhydantoin), which was the first hydantoin (briefly used as a hypnotic). However, nirvanol is quite toxic and mephenytoin was only considered after other less toxic anticonvulsants had failed. It can cause potentially fatal blood dyscrasia in 1% of patients. Mephenytoin is no longer available in the US or the UK. It is still studied largely because of its interesting hydroxylation In chemistry, hydroxylation refers to the installation of a hydroxyl group () into an organic compound. Hydroxylations generate alcohols and phenols, which are very common functional groups. Hydroxylation confers some degree of water-solubility ... polymorphism. References * * * Anticonvulsants Hydantoins {{anticonvulsant-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CYP2C19
Cytochrome P450 2C19 (abbreviated CYP2C19) is an enzyme protein. It is a member of the CYP2C subfamily of the cytochrome P450 mixed-function oxidase system. This subfamily includes enzymes that catalyze metabolism of xenobiotics, including some proton pump inhibitors and antiepileptic drugs. In humans, it is the ''CYP2C19'' gene that encodes the CYP2C19 protein. CYP2C19 is a liver enzyme that acts on at least 10% of drugs in current clinical use, most notably the antiplatelet treatment clopidogrel (Plavix), drugs that treat pain associated with ulcers, such as omeprazole, antiseizure drugs such as mephenytoin, the antimalarial proguanil, and the anxiolytic diazepam. CYP2C19 has been annotated as (R)-limonene 6-monooxygenase and (S)-limonene 6-monooxygenase in UniProt. Function The gene encodes a member of the cytochrome P450 superfamily of enzymes. Enzymes in the CYP2C subfamily, including CYP2C19, account for approximately 20% of cytochrome P450 in the adult liver. Thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticonvulsant
Anticonvulsants (also known as antiepileptic drugs, antiseizure drugs, or anti-seizure medications (ASM)) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also used in the treatment of bipolar disorder and borderline personality disorder, since many seem to act as mood stabilizers, and for the treatment of neuropathic pain. Anticonvulsants suppress the uncontrolled and excessive firing of neurons during seizures and in doing so can also prevent the spread of the seizure within the brain. Conventional antiepileptic drugs have diverse mechanisms of action but many block sodium channels or enhance γ-aminobutyric acid ( GABA) function. Several antiepileptic drugs have multiple or uncertain mechanisms of action. Next to voltage-gated sodium channels and components of the GABA system, their targets include GABAA receptors, the GABA transporter type 1, and GABA transaminase. Additional targets include voltage-gate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nirvanol
Nirvanol, also known as ethylphenylhydantoin, is a derivative of hydantoin with anticonvulsant properties. Its 5-ethyl-5-phenyl substitution pattern is similar to that of phenobarbital Phenobarbital, also known as phenobarbitone or phenobarb, sold under the brand name Luminal among others, is a medication of the barbiturate type. It is recommended by the World Health Organization (WHO) for the treatment of certain types of .... It is useful in the treatment of chorea. Metabolism Metabolism of nirvanol is stereoselective, with the (''S'')- enantiomer undergoing roughly 14 times more hydroxylation at the 4 position of the phenyl group than the (''R'')-enantiomer. References External links Comparative Toxicogenomics Database: ethylphenylhydantoinMeSH Supplementary Concept Data: ethylphenylhydantoin Anticonvulsants Hydantoins Phenyl compounds {{Anticonvulsant-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticonvulsants
Anticonvulsants (also known as antiepileptic drugs, antiseizure drugs, or anti-seizure medications (ASM)) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also used in the treatment of bipolar disorder and borderline personality disorder, since many seem to act as mood stabilizers, and for the treatment of neuropathic pain. Anticonvulsants suppress the uncontrolled and excessive firing of neurons during seizures and in doing so can also prevent the spread of the seizure within the brain. Conventional antiepileptic drugs have diverse mechanisms of action but many block sodium channels or enhance γ-aminobutyric acid ( GABA) function. Several antiepileptic drugs have multiple or uncertain mechanisms of action. Next to voltage-gated sodium channels and components of the GABA system, their targets include GABAA receptors, the GABA transporter type 1, and GABA transaminase. Additional targets include voltage-gated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydantoin
Hydantoin, or glycolylurea, is a heterocyclic organic compound with the formula CH2C(O)NHC(O)NH. It is a colorless solid that arises from the reaction of glycolic acid and urea. It is an oxidized derivative of imidazolidine. In a more general sense, hydantoins can refer to Functional group, groups or a class of compounds with the same ring structure as the parent compound. For example, phenytoin (mentioned below) has two phenyl groups substituted onto the number 5 carbon in a hydantoin molecule. Synthesis Hydantoin was first isolated in 1861 by Adolf von Baeyer in the course of his study of uric acid. He obtained it by hydrogenation of allantoin, hence the name. : Friedrich Urech synthesized 5-methylhydantoin in 1873 from alanine sulfate and potassium cyanate in what is now known as the Urech hydantoin synthesis. The method is very similar to the modern route using alkyl and arylcyanates. The 5,5-dimethyl compound can also be obtained from cyanohydrin, acetone cyanohydrin (als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenytoin
Phenytoin (PHT), sold under the brand name Dilantin among others, is an anticonvulsant, anti-seizure medication. It is useful for the prevention of tonic-clonic seizures (also known as grand mal seizures) and focal seizures, but not absence seizures. The intravenous form, fosphenytoin, is used for status epilepticus that does not improve with benzodiazepines. It may also be used for certain heart arrhythmias or neuropathic pain. It can be taken intravenously or by mouth. The intravenous form generally begins working within 30 minutes and is effective for roughly 24 hours. Blood levels can be measured to determine the proper dose. Common side effects include nausea, stomach pain, loss of appetite, poor coordination, hypertrichosis, increased hair growth, and Gingival hyperplasia, enlargement of the gums. Potentially serious side effects include sleepiness, self harm, liver problems, bone marrow suppression, hypotension, low blood pressure, toxic epidermal necrolysis, and atrop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metabolite
In biochemistry, a metabolite is an intermediate or end product of metabolism. The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, catalytic activity of their own (usually as a cofactor to an enzyme), defense, and interactions with other organisms (e.g. pigments, odorants, and pheromones). A primary metabolite is directly involved in normal "growth", development, and reproduction. Ethylene exemplifies a primary metabolite produced large-scale by industrial microbiology. A secondary metabolite is not directly involved in those processes, but usually has an important ecological function. Examples include antibiotics and pigments such as resins and terpenes etc. Some antibiotics use primary metabolites as precursors, such as actinomycin, which is created from the primary metabolite tryptophan. Some sugars are metabolites, such as fructose or glucose, which ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypnotic
A hypnotic (from Ancient Greek, Greek ''Hypnos'', sleep), also known as a somnifacient or soporific, and commonly known as sleeping pills, are a class of psychoactive drugs whose primary function is to sleep induction, induce sleep and to treat insomnia (sleeplessness). This group of drugs is related to sedatives''. ''Whereas the term sedative describes drugs that serve to calm or Anxiolytic, relieve anxiety, the term hypnotic generally describes drugs whose main purpose is to initiate, sustain, or lengthen sleep. Because these two functions frequently overlap, and because drugs in this class generally produce dose-dependent effects (ranging from anxiolysis to loss of consciousness), they are often referred to collectively as sedative–hypnotic drugs. Hypnotic drugs are regularly prescribed for insomnia and other sleep disorders, with over 95% of insomnia patients being prescribed hypnotics in some countries. Many hypnotic drugs are habit-forming and—due to many factors kno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyscrasia
In medicine, both ancient and modern, a dyscrasia is any of various disorders. The word has ancient Greek roots meaning "bad mixture". The concept of dyscrasia was developed by the Greek physician Galen (129–216 AD), who elaborated a model of health and disease as a structure of elements, qualities, humors, organs, and temperaments (based on earlier humorism). Health was understood in this perspective to be a condition of harmony or balance among these basic components, called eucrasia. Disease was interpreted as the disproportion of bodily fluids or four humours: phlegm, blood, yellow bile, and black bile. The imbalance was called dyscrasia. In modern medicine, the term is still occasionally used in medical context for an unspecified disorder of the blood, such as a plasma cell dyscrasia. Ancient use To the Greeks, it meant an imbalance of the four humors: blood, black bile, yellow bile, and water (phlegm). These humors were believed to exist in the body, and any change in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxylation
In chemistry, hydroxylation refers to the installation of a hydroxyl group () into an organic compound. Hydroxylations generate alcohols and phenols, which are very common functional groups. Hydroxylation confers some degree of water-solubility. Hydroxylation of a hydrocarbon is an oxidation, thus a step in degradation. Biological hydroxylation In biochemistry, hydroxylation reactions are often facilitated by enzymes called hydroxylases. These enzymes insert an O atom into a bond. Typical stoichiometries for the hydroxylation of a generic hydrocarbon are these: : : Since itself is a slow and unselective hydroxylating agent, catalysts are required to accelerate the pace of the process and to introduce selectivity. Hydroxylation is often the first step in the degradation of organic compounds in air. Hydroxylation is important in detoxification since it converts lipophilic compounds into water-soluble (hydrophilic) products that are more readily removed by the kidneys or liver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism (biology)
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative '' phenotypes'', in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Ford E.B. 1965. ''Genetic polymorphism''. Faber & Faber, London. Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
