Carboxylic acids continued groups

Systematic names for carboxylic acids are derived by counting the number of car bons m the longest continuous chain that includes the carboxyl group and replacing the e ending of the corresponding alkane by oic acid The first three acids m Table 19 1 methanoic (1 carbon) ethanoic (2 carbons) and octadecanoic acid (18 carbons) illus trate this point When substituents are present their locations are identified by number... 

Proteins are nature s polyamide condensation polymers. A protein is formed by polymerization of o-artiino acids, with the amino group on the carbon atom next to the carboxylic acid. Biologists call the bond formed a peptide rather than an amide. In the food chain these amino acids are continuously hydrolyzed and polymerized back into polymers, which the host can use in its tissues. These polymerization and depolymerization reactions in biological systems are all controlled by enzyme catalysts that produce extreme selectivity to the desired proteins. 

The reaction of epoxides with carboxylic acids in the presence of ammonium perchlorate can be very slow. The search for a catalyst to accelerate the cure rate for a particular formulation can be particularly rewarding. The slowness of the reaction can lead to a disadvantage of the system if not carefully investigated. If cure is stopped before all of the epoxide groups have been consumed, cure will continue at a rate which depends on storage temperature. The epoxide can continue to react with carboxyl groups rapidly at elevated temperatures, or very, very slowly at ambient temperature, to yield highly crosslinked propellant systems with low strain capability. 

The root name is based on the longest continuous chain of carbon atoms bearing the carhoxyl group. The -e is replaced by -oic acid. The chain is numbered starting with the carhoxyl carbon atom. The carboxyl group takes priority over any other functional groups as follows carboxylic acid > ester > amide > nitrile > aldehyde > ketone > alcohol > amine > alkene > alkyne. 

Besides the swelling transitions, the swelling behaviors below the critical pH have been considered. In Fig. 1, we see that swelling continues to increase as pH is lowered below the transition point. This behavior is seen when the gels are immersed in citrate buffered saline, and is due to the shift in the charge on the citrate counterions. Citrate buffer has three ionizable carboxylic acid groups, with pK values in water pKj = 3.15, pK2 = 4.78 and pK3 - 6.40. (These values are somewhat lower in salt solutions.) Thus as pH is lowered, the citrate passes... 

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