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Firstly, 2,4-dimethyl-6-tert-butylphenol is reacted with formaldehyde and HCl (Blanc reaction) to generate a chloromethyl group in the less hindered meta position. This intermediate then reacts with cyanuric acid to give the desired product.
Tris(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate is a chemical compound used as a polymer stabilizer in plastics. Like other hindered phenols it acts as a primary antioxidant. More than 1000 tonnes per year are used in the EU.
Octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate is significantly less volatile than simpler phenolic antioxidants such as butylhydroxytoluene (BHT). This makes it more suitable to stabilising plastics, as it is not driven out by the high temperatures experienced during plastic extrusion and moulding, [2] when they are heated to 150-320 °C (300–600 °F). [3]
Butalbital is not recommended as a first-line treatment because it impairs alertness, brings risk of dependence and addiction, and increases the risk that episodic headaches will become chronic. [5] When other treatments are unavailable or ineffective, butalbital may be appropriate if the patient can be monitored to prevent the development of ...
The chemical synthesis of BHT in industry has involved the reaction of p-cresol (4-methylphenol) with isobutylene (2-methylpropene), catalyzed by sulfuric acid: [11] CH 3 (C 6 H 4)OH + 2 CH 2 =C(CH 3) 2 → ((CH 3) 3 C) 2 CH 3 C 6 H 2 OH. Alternatively, BHT has been prepared from 2,6-di-tert-butylphenol by hydroxymethylation or aminomethylation ...
Each tablet contains 2, 4, or 8 mg of the tert-butylamine salt of perindopril. Perindopril is also available under the trade name Coversyl Plus, containing 4 mg of perindopril combined with 1.25 mg indapamide, a thiazide-like diuretic. In Australia, each tablet contains 2.5, 5, or 10 mg of perindopril arginine.
It can be prepared by base-catalyzed isomerization of 2,3-dimethyl-1-butene. [2] Another route involves direct dimerization of propylene . [ 3 ] It can also be produced by photolysis of tetramethylcyclobutane-1,3-dione .