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Thiuram Disulfides
Thiuram disulfides are a class of organosulfur compounds with the formula (R2NCSS)2. Many examples are known, but popular ones include R = Me and R = Et. They are disulfides obtained by oxidation of the dithiocarbamates. These compounds are used in sulfur vulcanization of rubber as well as in the manufacture of pesticides and drugs. They are typically white or pale yellow solids that are soluble in organic solvents. Preparation, structure, reactions Thiuram disulfides are prepared by oxidizing the salts of the corresponding dithiocarbamates (e.g. sodium diethyldithiocarbamate). Typical oxidants employed include chlorine and hydrogen peroxide: : Thiuram disulfides react with Grignard reagents to give esters of dithiocarbamic acid, as in the preparation of methyl dimethyldithiocarbamate: : The compounds feature planar dithiocarbamate subunits and are linked by an S−S bond of 2.00 Å. The C(S)−N bond is short (1.33 Å), indicative of multiple bonding. The dihedral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allergen
An allergen is an otherwise harmless substance that triggers an allergic reaction in sensitive individuals by stimulating an immune response. In technical terms, an allergen is an antigen that is capable of stimulating a type-I hypersensitivity reaction in atopic individuals through immunoglobulin E (IgE) responses. Most humans mount significant immunoglobulin E responses only as a defense against parasitic infections. However, some individuals may respond to many common environmental antigens. This hereditary predisposition is called atopy. In atopic individuals, non-parasitic antigens stimulate inappropriate IgE production, leading to type I hypersensitivity. Sensitivities vary widely from one person (or from one animal) to another. A very broad range of substances can be allergens to sensitive individuals. Examples Allergens can be found in a variety of sources, such as dust mite excretion, pollen, pet dander, or even royal jelly. Food allergies are not as co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hangover
A hangover is the experience of various unpleasant physiological and psychological effects usually following the consumption of alcohol (beverage), alcohol, such as wine, beer, and liquor. Hangovers can last for several hours or for more than 24 hours. Typical symptoms of a hangover may include headache, Somnolence, drowsiness, weakness, concentration problems, Xerostomia, dry mouth, dizziness, fatigue (medical), fatigue, muscle ache, gastrointestinal distress (e.g., nausea, vomiting, diarrhea), Anorexia (symptom), absence of hunger, Photophobia, light sensitivity, Depression (mood), depression, Perspiration, sweating, hyper-excitability, high blood pressure, irritability, and Anxiety attack, anxiety. While the causes of a hangover are still poorly understood, several factors are known to be involved including acetaldehyde accumulation, changes in the immune system and glucose metabolism, dehydration, metabolic acidosis, disturbed prostaglandin synthesis, increased cardiac out ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetaldehyde Dehydrogenase
Acetaldehyde dehydrogenases () are dehydrogenase enzymes which catalyze the conversion of acetaldehyde into acetyl-CoA. This can be summarized as follows: Acetaldehyde + NAD+ + Coenzyme A ↔ Acetyl-CoA + NADH + H+ In humans, there are three known genes which encode this enzymatic activity, ''ALDH1A1'', ''ALDH2'', and the more recently discovered '' ALDH1B1'' (also known as '' ALDH5''). These enzymes are members of the larger class of aldehyde dehydrogenases. The CAS number for this type of the enzyme is 028-91-5 Structure Cysteine-302 is one of three consecutive Cys residues and is crucial to the enzyme's catalytic function. The residue is alkylated by iodoacetamide in both the cytosolic and mitochondrial isozymes, with modifications to Cys-302 indicative of catalytic activity with other residues. Furthermore, the preceding sequence Gln-Gly-Gln-Cys is conserved in both isozymes for both human and horse, which is consistent with Cys-302 being crucial to catalytic function. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetaldehyde
Acetaldehyde (IUPAC systematic name ethanal) is an organic compound, organic chemical compound with the chemical formula, formula , sometimes abbreviated as . It is a colorless liquid or gas, boiling near room temperature. It is one of the most important aldehydes, occurring widely in nature and being produced on a large scale in industry. Acetaldehyde occurs naturally in coffee, bread, and ripe fruit, and is produced by plants. It is also produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase and is a contributing cause of hangover after alcohol (drug), alcohol consumption. Pathways of exposure include air, water, land, or groundwater, as well as drink and smoke. Consumption of disulfiram inhibits acetaldehyde dehydrogenase, the enzyme responsible for the metabolism of acetaldehyde, thereby causing it to build up in the body. International Agency for Research on Cancer, The International Agency for Research on Cancer (IARC) has listed acetaldehyde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcoholism
Alcoholism is the continued drinking of alcohol despite it causing problems. Some definitions require evidence of dependence and withdrawal. Problematic use of alcohol has been mentioned in the earliest historical records. The World Health Organization (WHO) estimated there were 283 million people with alcohol use disorders worldwide . The term ''alcoholism'' was first coined in 1852, but ''alcoholism'' and ''alcoholic'' are considered stigmatizing and likely to discourage seeking treatment, so diagnostic terms such as ''alcohol use disorder'' and ''alcohol dependence'' are often used instead in a clinical context. Alcohol is addictive, and heavy long-term alcohol use results in many negative health and social consequences. It can damage all the organ systems, but especially affects the brain, heart, liver, pancreas, and immune system. Heavy alcohol usage can result in trouble sleeping, and severe cognitive issues like dementia, brain damage, or Wernicke–Kors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disulfiram
Disulfiram is a medication used to support the treatment of chronic alcoholism by producing an acute sensitivity to ethanol (drinking alcohol). Disulfiram works by Enzyme inhibition, inhibiting the enzyme aldehyde dehydrogenase (specifically ALDH2), causing many of the effects of a hangover to be felt immediately following alcohol (drug), alcohol consumption. Disulfiram plus alcohol, even small amounts, produces flushing, throbbing in the head and neck, a throbbing headache, respiratory difficulty, nausea, copious vomiting, sweating, thirst, chest pain, palpitation, dyspnea, shortness of breath, hyperventilation, tachycardia, fast heart rate, hypotension, low blood pressure, Syncope (medicine), fainting, marked uneasiness, weakness, vertigo, blurred vision, and confusion. In severe reactions there may be respiratory depression, cardiovascular collapse, arrhythmia, abnormal heart rhythms, myocardial infarction, heart attack, acute congestive heart failure, unconsciousness, convulsi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiram
Thiram is the simplest thiuram disulfide and the oxidized dimer of dimethyldithiocarbamate. It is used as a fungicide, ectoparasiticide to prevent fungal diseases in seed and crops and similarly as an animal repellent to protect fruit trees and ornamentals from damage by rabbits, rodents and deer. It is effective against Stem gall of coriander, damping off, smut of millet, neck rot of onion, etc. Thiram has been used in the treatment of human scabies, as a sun screen and as a bactericide applied directly to the skin or incorporated into soap. Thiram is also used as a sulfur source and secondary accelerator the sulfur vulcanization Sulfur vulcanization is a chemical process for converting natural rubber or related polymers into materials of varying hardness, elasticity, and mechanical durability by heating them with sulfur or sulfur-containing compounds. Sulfur forms cros ... of rubbers. Usage Thiram was traditionally used in apple and wine farming. Since 2010 most thira ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiocarbamoyl Chloride
Dimethylthiocarbamoyl chloride is an organosulfur compound with the formula (CH3)2NC(S)Cl. A yellow solid, it is often encountered as a yellow syrup. It is a key reagent in the synthesis of arylthiols via the Newman-Kwart rearrangement. Synthesis and reactions Representative of other thiocarbamoyl chlorides, dimethylthiocarbamoyl chloride is electrophilic, serving as a source of R2NC(S)+.R. J. Cremlyn "An Introduction to Organosulfur Chemistry" John Wiley and Sons: Chichester (1996). It is analogous to dimethylcarbamoyl chloride (R2NC(O)Cl). Dimethylthiocarbamoyl chloride is prepared by chlorination of the related tetramethylthiuram disulfide: : e2NC(S)sub>2S2 + 3 Cl2 → 2 Me2NC(S)Cl + 2 SCl2 Dimethylthiocarbamoyl chloride reacts with dithiocarbamates (R2NCS{{su, b=2, p=−) to give thiuram sulfides 2NC(S)sub>2S. With methanethiolate, it gives methyl dimethyldithiocarbamate Methyl dimethyldithiocarbamate is the organosulfur compound with the formula . It is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triphenylphosphine Sulfide
Triphenylphosphine sulfide (IUPAC name: triphenyl-''λ''5-phosphanethione) is the organophosphorus compound with the formula , usually written (where Ph = phenyl). It is a colourless solid, which is soluble in a variety of organic solvents. Structurally, the molecule resembles the corresponding oxide, with idealized C3 point group symmetry. It is weakly nucleophilic at the sulfur atom. Applications Organic synthesis Triphenylphosphine sulfide is useful for the conversion of epoxides to the corresponding episulfides: : It also reacts with ketenes to form thioketenes: : Analytical chemistry In analytical chemistry, triphenylphosphine is used for the analysis of certain kinds of sulfur compounds. Elemental sulfur (), as occurs in some oils, and labile organosulfur compounds, such as organic trisulfides, react with triphenylphosphine to give , which can be detected by gas chromatography Gas chromatography (GC) is a common type of chromatography used in analytical chemistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetramethylthiuram Sulfide
Tetramethylthiuram sulfide is an organosulfur compound with the formula ((CH3)2NCS)2S. It is a yellow solid that is soluble in organic solvents. It is the parent member of a large class of tetraalkylthiuram sulfides. It is used as an activator in the sulfur vulcanization of natural and butyl rubbers. Synthesis and structure It is prepared by desulfuration of tetramethylthiuram disulfides with triphenylphosphine or cyanide: :(Me2NCSS)2 + PPh3 → (Me2NCS)2S + SPPh3 According to X-ray crystallography, the molecule consists of two planar (CH3)2NCS subunits joined by a sulfide Sulfide (also sulphide in British English) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. ''Sulfide'' also refers to large families o .... The dihedral angle between the subunits is close to 90°. References Organosulfur compounds {{organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
