Acta Pharmaceutica, Vol. 56 No. 2, 2006.
Kratko priopćenje
Esterification of 7-theophyllineacetic acid with diethylene glycol monomethyl ether
BOIKA TSVETKOVA
JASMINA TENCHEVA
PLAMEN PEIKOV
Sažetak
The kinetics of еsterification of 7-theophyllineacetic acid with diethylene glycol monomethyl ether in the presence of dicyclohexylcarbodiimide and 4-dimethylaminopyridine as catalyst was studied. According to the known mechanism, besides the main process, the side-reaction of intramolecular rearrangement with formation of pharmacologically active N-acylurea occurs. The course of the main and the side-process was monitored by RP-HPLC with UV-detection. For that purpose, quantification of both ester and N-acylurea in the reaction mixture was performed. Influence of the concentration of the reactants (acid, alcohol and catalyst) on the progress of esterification and preparation of the by-product was investigated. Based on the obtained results, the reaction conditions leading to maximal yield of the ester and N-acylurea are proposed. Possibility of turning esterification to the synthesis of the side-product was also found. Reactions of the preparation of both the ester and N-acylurea were found to follow first-order kinetics. The rate constants of both processes were estimated.
Ključne riječi
7-theophyllineacetic acid ester; N-acylurea; dicyclohexylcarbodiimide; 4-dimethylaminopyridine; esterification; kinetics
Hrčak ID:
4560
URI
Datum izdavanja:
1.6.2006.
Posjeta: 4.577 *