ABSTRACT
Objective: To optimize and establish the best hydrolysis method of diethyl ester 4-amino-N5-formyl-N8,N10-dideazatetrahydrofolate through the optimization of simple compound of diethyl N-(4-aminobenzoyl)-L-glutamate.Methods: To increase the low yield of hydrolysis reaction of diethyl ester 4-amino-N5-formyl-N8,N10-dideazatetrahydrofolate due to the by-products and difficult purification, we studied the effect of NaOH and KOH, two kinds of alkalis, three concentrations between 0.175-1 mol/L and five types of reaction time involved in 20, 30, 60, 120 and 180 min on the common side chain diethyl N-(4-aminobenzoyl)-L-glutamate.A high performance liquid chromatography was established for measuring the target product and the by-products in reaction liquid in different reaction conditions.Finally, on the basis of the best hydrolysis method of diethyl ester 4-amino-N5-formyl-N8,N10-dideazatetrahydrofolate, we completed the optimization of the hydrolysis reaction conditions of diethyl ester 4-amino-N5-formyl-N8,N10-dideazatetrahydrofolate.Results: We developed the best reaction condition for the hydrolysis of diethyl ester 4-amino-N5-formyl-N8,N10-dideazatetrahydrofolate, which could be carried out easily and efficiently.The results indicated that treated with the optimized condition of 0.3 mol/L KOH in 60 min at the room temperature, diethyl ester 4-amino-N5-formyl-N8,N10-dideazatetrahydrofolate was converted into its diacid derivative in 95.6 % yield, which turned to be a better reaction condition compared with the previous reaction condition.The structures of those compounds were identified to be correct by 1H nuclear magnetic resonance(1H NMR), 13C nuclear magnetic resonance(13C NMR) and electrospray ionization time of flight mass spectrometry (ESI-MS).The purity of the diacid derivative of the compound was determined to be 96% by high performance liquid chromatography(HPLC).The new hydrolysis reaction condition could not only avoid the formation of single ester hydrolysis product and amide bond hydrolysis product, but also improve the yield of the hydrolysis reaction.Conclusion: We have developed an efficient reaction for the hydrolysis of diethyl ester 4-amino-N5-formyl-N8,N10-dideazatetrahydro.Since the final step of the synthesis of classical folic acid antagonists is always the catalyzed hydrolysis of the side chain glutamate, the reaction also has great significance for anti-folic acid anti-tumor inhibitors synthesis.
ABSTRACT
Objective:To establish a new approach to synthesis of diethyl N-[4-[(2,4-diaminopyrido [3,2-d]pyrimidin-6-yl)methylamino]benzoyl]-L-glutamate.Methods:Target compound (5) was syn-thesized by the use of (2,4-dioxo-tetrahydropyridopyrimidin-6-yl) methyl acetate (1) as starting material via hydrolysis, chlorination, condensation with diethyl (p-aminobenzoyl)glutamate and aminolysis.Re-sults:A new approach to synthesis of diethyl N-[4-[(2,4-diaminopyrido[3,2-d]pyrimidin-6-yl)methyl-amino]benzoyl]-L-glutamatewas established .This synthetic route has hydrolysis reaction , chlorination, diethyl N-( p-aminobenzoyl )-L-glutamate condensation reaction and ammonolysis reaction .The total yield is 36.7%.The structures of those compounds have identified by 1 H nuclear magnetic resonance , 13 C nu-clear magnetic resonance and mass spectrometry .This synthetic route avoid the unstable brominated re-action product and improves the harsh condition of ammonolysis reaction .Conclusion:The new synthetic route has improved the reaction condition and the stability of the intermediate , and increased the extent of the derivative compounds , which has great significance to anti-folic acid of anti-tumor inhibitor synthesis .