Catechol-containing inhibitors

They are generally active at the two steps of the integration but are not selective for IN and the practical utility of those catechol-containing inhibitors is severely reduced by cytotoxicity even though they have been found to inhibit HIV-1 integrase in vitro. Nevertheless, lithospermic acids, Fig. (19) were found to be active on purified IN as well as on HIV-1 infected H9 cells, and showed no cytotoxicity to H9 cells [80]. 

CHEMICAL PROPERTIES combustible liquid reacts vigorously with acids, oxidizing materials peroxides, polymer initiators, and metal salts such as iron chloride or aluminum chloride usually contains inhibitors, such as tert-butyl catechol, to prevent polymerization pure vapor will be uninhibited and may polymerize FP (53°C, 127°F) LFLAJFL (0.8%, 11.0%) AT (494°C, 921°F) HC (4,816.54 kJ/mol gas at 25°C) HF (115.48 kJ/mol liquid at 25°C) HP (66.9 or -0.2 kJ/mol). 

A recent case described the synthesis of more stable bioisosteres of inhibitors of the insulin-like growth factor-1 receptor kinase (Figure 15.43). Based on the structure of AG 538 ° which contains two catechol rings and is sensitive to oxidation in cell, a new series of kinase inhibitors were developed. The catechol moiety was replaced by a benzoxazolone ring resistant to oxidation yielding two compounds GB19 and AGL2263 which maintain same potency as AG 538. 

Determination of TBC in Styrene To determine the amount of inhibitor p-tert butyl catechol (TBC) present, the styrene monomer is extracted with aqueous NaOH and the aqueous layer containing the TBC as the coloured quinone is separated and the colour measured spectrophotmetrically at a wavelength of 485 run using NaOH of 1.0 N solution as a reference standeud. ASTM Method (D2120-82) is used for determining concentration of inhibitor, in styrene monomer. This method covers the measurement of the amount of residual TBC iii styrene monomer in the range from 0-100 ppm. 

CHEMICAL PROPERTIES stable under ordinary conditions of use and storage subject to polymerization by heat or catalysts usually contains an inhibitor such as tert-butyl catechol reacts with strong oxidants FP (54°C, 129°F) LFL/UFL (1.9%, 6.1%) AT (574°C, 1065°F). 

Minor Components. Besides the two major components, commercial considerations necessitate a third type of compound. If an unsaturated p yester and pure styrene are mixed together, copolymerization may take p e quickly. This is particularly true if the polyester is warm or hot at the time of addition. However, commercial styrene contains lOppm of t-butyl catechol as a storage stabilizer, and some storage stability is thus imparted to the polyester reran. This low amount is usually inadequate. One of the first major problems in the industry was to find an inhibitor which would provide sufficient time for ordinary shipping and consumption. Fortunately, several types of cpmpounds have been found which provide adequate stability for 6 months to a year. Hydroquinone and some of its alkyl-substituted derivatives are effective stabilizers. Catechol and some... 

Incompatibilities and Reactivities Oxidizers, peroxides, halogens, catalysts for vinyl or ionic polymers aluminum, iron chloride, copper [Note Usually contains an inhibitor such as tert-butyl catechol.]... 

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