Reaction #1446639

Reaction equation

2,4,6-triamino-5-nitrosopyrimidine

2,4-diamino-6-hydroxypyrimidine

toluene-4-sulfonic acid monohydrate

→

pyrimido[5,4-g]pteridine

Solvents

acetic acid

Conditions

Workup

1. 1
   FiltrationThe reaction mixture is filtered off over a laminated paper
2. 2
   Filtrationfilter while still hot, and the residue
3. 3
   Washis washed with hot water (approx. 60° C.) until the pH of the washing water
4. 4
   DryingThe washed residue, moist with water, is dried in vacuo at 110° C.

Procedure

A suspension of 6.20 g of commercial 2,4,6-triamino-5-nitrosopyrimidine (Chemie Uetikon, Lahr, Germany), 5.15 g of commercial 2,4-diamino-6-hydroxypyrimidine (Fluka, Buchs, Switzerland) and 11.52 g of commercial toluene-4-sulfonic acid monohydrate in 110 ml of glacial acetic acid (100%) is stirred for 20 hours at 113° C. The reaction mixture is filtered off over a laminated paper filter while still hot, and the residue is washed with hot water (approx. 60° C.) until the pH of the washing water has reached a value of at least 4. The washed residue, moist with water, is dried in vacuo at 110° C. to yield a greenish-yellow powder of the pyrimido[5,4-g]pteridine salt of formula VI

Source