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Methiocarb
Methiocarb is a carbamate pesticide (an acetylecholinesterase inhibitor) which is used as an insecticide, bird repellent, acaricide and molluscicide since the 1960s. Methiocarb has contact and stomach action on mites and neurotoxic effects on molluscs. Seeds treated with methiocarb also affect birds. Other names for methiocarb are mesurol and mercaptodimethur. Due to its toxicity, methiocarb approval as a plant protection product has been withdrawn by the EU effective 2020. Structure and reactivity The carbamate functional group in methiocarb can be cleaved by cholinesterase to result in the carbamate, which binds to the cholinesterase, and the aromatic alcohol. Synthesis Methiocarb (3) is synthesised by Bayer from 4-methylthio-3,5-xylenol (1) and methyl isocyanate (2). The xylenol (1) will act as the nucleophile in this reaction attacking the partially positively charged carbon in the isocyanate (2). Mechanism of action Methiocarb acts by acetylcholinesterase inhibition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesurol
Methiocarb is a carbamate pesticide (an acetylecholinesterase inhibitor pesticide, acetylecholinesterase inhibitor) which is used as an insecticide, bird repellent, acaricide and molluscicide since the 1960s. Methiocarb has contact and stomach action on mites and neurotoxin, neurotoxic effects on molluscs. Seeds treated with methiocarb also affect birds. Other names for methiocarb are mesurol and mercaptodimethur. Due to its toxicity, methiocarb approval as a plant protection product has been withdrawn by the EU effective 2020. Structure and reactivity The carbamate functional group in methiocarb can be cleaved by cholinesterase to result in the carbamate, which binds to the cholinesterase, and the aromatic alcohol. Synthesis Methiocarb (3) is synthesised by Bayer from 4-methylthio-3,5-xylenol (1) and methyl isocyanate (2). The xylenol (1) will act as the nucleophile in this reaction attacking the partially positively charged carbon in the isocyanate (2). Mechanism of action ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methiocarb Synthesis
Methiocarb is a carbamate pesticide (an acetylecholinesterase inhibitor) which is used as an insecticide, bird repellent, acaricide and molluscicide since the 1960s. Methiocarb has contact and stomach action on mites and neurotoxic effects on molluscs. Seeds treated with methiocarb also affect birds. Other names for methiocarb are mesurol and mercaptodimethur. Due to its toxicity, methiocarb approval as a plant protection product has been withdrawn by the EU effective 2020. Structure and reactivity The carbamate functional group in methiocarb can be cleaved by cholinesterase to result in the carbamate, which binds to the cholinesterase, and the aromatic alcohol. Synthesis Methiocarb (3) is synthesised by Bayer from 4-methylthio-3,5-xylenol (1) and methyl isocyanate (2). The xylenol (1) will act as the nucleophile in this reaction attacking the partially positively charged carbon in the isocyanate (2). Mechanism of action Methiocarb acts by acetylcholinesterase inhibition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methiocarb Metabolism
Methiocarb is a carbamate pesticide (an acetylecholinesterase inhibitor) which is used as an insecticide, bird repellent, acaricide and molluscicide since the 1960s. Methiocarb has contact and stomach action on mites and neurotoxic effects on molluscs. Seeds treated with methiocarb also affect birds. Other names for methiocarb are mesurol and mercaptodimethur. Due to its toxicity, methiocarb approval as a plant protection product has been withdrawn by the EU effective 2020. Structure and reactivity The carbamate functional group in methiocarb can be cleaved by cholinesterase to result in the carbamate, which binds to the cholinesterase, and the aromatic alcohol. Synthesis Methiocarb (3) is synthesised by Bayer from 4-methylthio-3,5-xylenol (1) and methyl isocyanate (2). The xylenol (1) will act as the nucleophile in this reaction attacking the partially positively charged carbon in the isocyanate (2). Mechanism of action Methiocarb acts by acetylcholinesterase inhibition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercaptodimethur
Methiocarb is a carbamate pesticide (an acetylecholinesterase inhibitor) which is used as an insecticide, bird repellent, acaricide and molluscicide since the 1960s. Methiocarb has contact and stomach action on mites and neurotoxic effects on molluscs. Seeds treated with methiocarb also affect birds. Other names for methiocarb are mesurol and mercaptodimethur. Due to its toxicity, methiocarb approval as a plant protection product has been withdrawn by the EU effective 2020. Structure and reactivity The carbamate functional group in methiocarb can be cleaved by cholinesterase to result in the carbamate, which binds to the cholinesterase, and the aromatic alcohol. Synthesis Methiocarb (3) is synthesised by Bayer from 4-methylthio-3,5-xylenol (1) and methyl isocyanate (2). The xylenol (1) will act as the nucleophile in this reaction attacking the partially positively charged carbon in the isocyanate (2). Mechanism of action Methiocarb acts by acetylcholinesterase inhibition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylcholinesterase Inhibitor Pesticide
Acetylcholinesterase inhibitors (AChEIs) also often called cholinesterase inhibitors, inhibit the enzyme acetylcholinesterase from breaking down the neurotransmitter acetylcholine into choline and acetate, thereby increasing both the level and duration of action of acetylcholine in the central nervous system, autonomic ganglia and neuromuscular junctions, which are rich in acetylcholine receptors. Acetylcholinesterase inhibitors are one of two types of cholinesterase inhibitors; the other being butyryl-cholinesterase inhibitors. Acetylcholinesterase is the primary member of the cholinesterase enzyme family. Acetylcholinesterase inhibitors are classified as reversible, irreversible, or quasi-irreversible (also called pseudo-irreversible). Mechanism of action Organophosphates Organophosphates like TEPP and sarin inhibit cholinesterases, enzymes that hydrolyze the neurotransmitter acetylcholine. The active centre of cholinesterases feature two important sites, namely the an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organophosphates
In organic chemistry, organophosphates (also known as phosphate esters, or OPEs) are a class of organophosphorus compounds with the general structure , a central phosphate molecule with alkyl or aromatic substituents. They can be considered as esters of phosphoric acid. Like most functional groups, organophosphates occur in a diverse range of forms, with important examples including key biomolecules such as DNA, RNA and ATP, as well as many insecticides, herbicides, nerve agents and flame retardants. OPEs have been widely used in various products as flame retardants, plasticizers, and performance additives to engine oil. The popularity of OPEs as flame retardants came as a substitution for the highly regulated brominated flame retardants. The low cost of production and compatibility to diverse polymers made OPEs to be widely used in industry including textile, furniture, electronics as plasticizers and flame retardants. These compounds are added to the final product physi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholinergic
Cholinergic agents are compounds which mimic the action of acetylcholine and/or butyrylcholine. In general, the word "choline" describes the various quaternary ammonium salts containing the ''N'',''N'',''N''-trimethylethanolammonium cation. Found in most animal tissues, choline is a primary component of the neurotransmitter acetylcholine and functions with inositol as a basic constituent of lecithin. Choline also prevents fat deposits in the liver and facilitates the movement of fats into cells. The parasympathetic nervous system, which uses acetylcholine almost exclusively to send its messages, is said to be almost entirely cholinergic. Neuromuscular junctions, preganglionic neurons of the sympathetic nervous system, the basal forebrain, and brain stem complexes are also cholinergic, as are the receptor for the merocrine sweat glands. In neuroscience and related fields, the term cholinergic is used in these related contexts: * A substance (or ligand) is cholinergic if it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocrine Disruptor
Endocrine disruptors, sometimes also referred to as hormonally active agents, endocrine disrupting chemicals, or endocrine disrupting compounds are chemicals that can interfere with endocrine (or hormonal) systems. These disruptions can cause cancerous tumors, birth defects, and other developmental disorders. Found in many household and industrial products, endocrine disruptors "interfere with the synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body that are responsible for development, behavior, fertility, and maintenance of homeostasis (normal cell metabolism)." Any system in the body controlled by hormones can be derailed by hormone disruptors. Specifically, endocrine disruptors may be associated with the development of learning disabilities, severe attention deficit disorder, cognitive and brain development problems. There has been controversy over endocrine disruptors, with some groups calling for swift action by regulators to re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin Irritant
Irritation, in biology and physiology, is a state of inflammation or painful reaction to allergy or cell-lining damage. A stimulus or agent which induces the state of irritation is an irritant. Irritants are typically thought of as chemical agents (for example phenol and capsaicin) but mechanical, thermal (heat), and radiative stimuli (for example ultraviolet light or ionising radiations) can also be irritants. Irritation also has non-clinical usages referring to bothersome physical or psychological pain or discomfort. Irritation can also be induced by some allergic response due to exposure of some allergens for example contact dermatitis, irritation of mucosal membranes and pruritus. Mucosal membrane is the most common site of irritation because it contains secretory glands that release mucous which attracts the allergens due to its sticky nature. Chronic irritation is a medical term signifying that afflictive health conditions have been present for a while. There are many dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Estrogen
Estrogen or oestrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal activity: estrone (E1), estradiol (E2), and estriol (E3). Estradiol, an estrane, is the most potent and prevalent. Another estrogen called estetrol (E4) is produced only during pregnancy. Estrogens are synthesized in all vertebrates and some insects. Their presence in both vertebrates and insects suggests that estrogenic sex hormones have an ancient evolutionary history. Quantitatively, estrogens circulate at lower levels than androgens in both men and women. While estrogen levels are significantly lower in males than in females, estrogens nevertheless have important physiological roles in males. Like all steroid hormones, estrogens readily diffuse across the cell membrane. Once inside the cell, they bind to and activate estrogen receptors (E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nucleophile
In chemistry, a nucleophile is a chemical species that forms bonds by donating an electron pair. All molecules and ions with a free pair of electrons or at least one pi bond can act as nucleophiles. Because nucleophiles donate electrons, they are Lewis bases. ''Nucleophilic'' describes the affinity of a nucleophile to bond with positively charged atomic nuclei. Nucleophilicity, sometimes referred to as nucleophile strength, refers to a substance's nucleophilic character and is often used to compare the affinity of atoms. Neutral nucleophilic reactions with solvents such as alcohols and water are named solvolysis. Nucleophiles may take part in nucleophilic substitution, whereby a nucleophile becomes attracted to a full or partial positive charge, and nucleophilic addition. Nucleophilicity is closely related to basicity. History The terms ''nucleophile'' and ''electrophile'' were introduced by Christopher Kelk Ingold in 1933, replacing the terms ''anionoid'' and ''cationoid' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatase Inhibitor
Aromatase inhibitors (AIs) are a class of drugs used in the treatment of breast cancer in postmenopausal women and in men, and gynecomastia in men. They may also be used off-label to reduce estrogen conversion when supplementing testosterone exogenously. They may also be used for chemoprevention in women at high risk for breast cancer. Aromatase is the enzyme that catalyzes a key aromatization step in the synthesis of estrogen. It converts the enone ring of androgen precursors such as testosterone, to a phenol, completing the synthesis of estrogen. As such, AIs are estrogen synthesis inhibitors. Because hormone-positive breast and ovarian cancers are dependent on estrogen for growth, AIs are taken to either block the production of estrogen or block the action of estrogen on receptors. Medical uses Cancer In contrast to premenopausal women, in whom most of the estrogen is produced in the ovaries, in postmenopausal women estrogen is mainly produced in peripheral tissues of the bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
