107809-86-9Relevant academic research and scientific papers
Selectively 13C-Enriched 2,4-Diamino-5-(3,4,5-trimethoxybenzyl)pyrimidine (Trimethoprim) and 2,4-Diaminopyrimidine
Smal, Mary,Cheung, H. T. Andrew,Davies, Peter E.
, p. 747 - 752 (2007/10/02)
Samples of 2,4-diamino-5-(3,4,5-trimethoxybenzyl)pyrimidine (Trimethoprim) were synthesized, enriched with 13C at the following positions: 2 and 5; 4 and 6; α and 4-methoxy.For the first two series (having 13C-enrichment at the pyrimidine), appropriately labelled cyanoacetic acid was converted into labelled methyl 2-(3,4,5-trimethoxybenzyl)cyanoacetate and thence to the labelled 6-hydroxy derivative of Trimethoprim.For the last series (having 13C-enrichment at the trimethoxybenzyl moiety), the key reaction was the nucleophilic attack of C-5 of 2,4-diamino-6-hydroxypyrimidine on labelled 3,4,5-trimethoxybenzyl bromide, again yielding the labelled 6-hydroxy derivative of Trimethoprim.The conversion of the 6-hydroxy derivatives into 13C enriched Trimethoprim was via the 6-chloride.Also synthesized was -2,4-diaminopyrimidine by cyclization of guanidine and -3-anilino-acrylonitrile.The identity, and the site(s) of the 13C label(s) of each final product and intermediate, were established on the basis of 1H and 13C n.m.r. spectral evidence.
