5148-09-4

Upstream product

• 6965-19-1 2-ethylthio-3H-pyrimidin-4-one 
• 75-03-6 ethyl iodide 
• 253142-21-1 3-ethyl-2-methoxy-4-pyrimidinone 
• 66-22-8 uracil 
• 64-67-5 diethyl sulfate 

Downstream Products

• 131728-33-1 N-(phenyl)-N-[1-(2-(1,2,3,4-tetrahydro-2,4-dioxo-3-ethylpyrimidin-1-yl)-ethyl)-4-methoxycarbonyl-4-piperidinyl]propanamide 
• 131728-35-3 N-(phenyl)-N-[1-(2-(1,2,3,4-tetrahydro-2,4-dioxo-3-ethylpyrimidin-1-yl)-ethyl)-4-methoxymethyl-4-piperidinyl]propanamide 

Relevant academic research and scientific papers

A diversity of alkylation/acylation products of uracil and its derivatives: Synthesis and a structural study

tert-Butyl dicarbonate (Boc2O) and ethyl iodide (EtI) reactions with uracil (U), thymine (T) and 6-methyluracil (6-MU) were performed following routine procedures in pyridine/DMF solvents and with DMAP as the catalyst. Among 20 synthesized compounds, a derivative of 6-methyluracil substituted by the Boc-pyridine moiety at the C5 position appeared unexpectedly. The NMR spectra confirmed the molecular structure of all uracil derivatives. Parallel quantum mechanical DFT calculations supported the experimental findings.

HSAB-driven chemoselective N1-alkylation of pyrimidine bases and their 4-methoxy- or 4-acetylamino-derivatives

The lithium salts of the conjugated bases of 4-methoxy- and 4-acetylamino-2(1H)-pyrimidinones 1-3 undergo highly chemoselective N1-methylation or ethylation when treated with methyl- or ethylsulfate (hard electrophiles) in dry dioxane, while the use of DMF as solvent results in competitive O2-alkylation. Potassium salts of the same bases in DMF undergo prevalent O2-attack. Under the same conditions, a similar but less chemoselective behaviour is observed in alkylation of thymine and uracil, where some N3-attack occurs. This can be rationalised in terms of the HSAB principle.

HSAB driven chemoselectivity in alkylation of uracil derivatives. A high yielding preparation of 3-alkylated and unsymmetrically 1,3-dialkylated uracils

A qualitative hardness scale (N134) has been found for the conjugated bases of 2-methoxy-4(3H)-pyrimidinones 1-3 and applied to high yielding chemoselective N3 methylation, ethylation and benzylation reactions. Removal of the 2-methoxy group followed by a second alkylation affords unsymmetrically 1,3-disubstituted uracils.