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Beta-adrenergic Agonist
Beta adrenergic agonists or beta agonists are medications that relax muscles of the airways, causing widening of the airways and resulting in easier breathing. They are a class of sympathomimetic agents, each acting upon the beta adrenoceptors. In general, pure beta-adrenergic agonists have the opposite function of beta blockers: beta-adrenoreceptor agonist ligands mimic the actions of both epinephrine- and norepinephrine- signaling, in the heart and lungs, and in smooth muscle tissue; epinephrine expresses the higher affinity. The activation of β1, β2 and β3 activates the enzyme, adenylate cyclase. This, in turn, leads to the activation of the secondary messenger cyclic adenosine monophosphate (cAMP); cAMP then activates protein kinase A (PKA) which phosphorylates target proteins, ultimately inducing smooth muscle relaxation and contraction of the cardiac tissue. Function Activation of β1 receptors induces positive inotropic, chronotropic output of the cardiac muscle, lead ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahydroisoquinolines
Tetrahydroisoquinoline (TIQ or THIQ) is an organic compound with the chemical formula C9H11N. Classified as a secondary amine, it is derived from isoquinoline by hydrogenation. It is a colorless viscous liquid that is miscible with most organic solvents. The tetrahydroisoquinoline skeleton is encountered in a number of bioactive compounds and drugs. Reactions As a secondary amine, tetrahydroisoquinoline has weakly basic properties and forms salts with strong acids. It can be dehydrogenated to give isoquinoline and hydrogenated to decahydroisoquinoline. Like other secondary amines, tetrahydroisoquinoline can be oxidized to the corresponding nitrone using hydrogen peroxide, catalyzed by selenium dioxide. Toxicology Tetrahydroisoquinoline derivatives may be formed in the body as metabolites of some drugs, and this was once thought to be involved in the development of alcoholism. This theory has now been discredited and is no longer generally accepted by the scientific community, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catechols
Catechol ( or ), also known as pyrocatechol or 1,2-dihydroxybenzene, is a toxic organic compound with the molecular formula . It is the ''ortho'' isomer of the three isomeric benzenediols. This colorless compound occurs naturally in trace amounts. It was first discovered by destructive distillation of the plant extract catechin. About 20,000 tonnes of catechol are now synthetically produced annually as a commodity organic chemical, mainly as a precursor to pesticides, flavors, and fragrances. Catechol occurs as feathery white crystals that are very rapidly soluble in water. Isolation and synthesis Catechol was first isolated in 1839 by Edgar Hugo Emil Reinsch (1809–1884) by distilling it from the solid tannic preparation catechin, which is the residuum of catechu, the boiled or concentrated juice of ''Mimosa catechu'' (''Acacia catechu''). Upon heating catechin above its decomposition point, a substance that Reinsch first named ''Brenz-Katechusäure'' (burned catechu acid) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
