Process for preparation of 9-(dihalobenzyl)adenines

Abstract

9-(Dihalobenzyl)adenines are prepared uncontaminated with other positional isomers in a series of mild transformations starting from 4,5,6-triaminopyrimidine and proceeding via 7-(N-formyl-N-dihalobenzyl)amino[1,2,5]-thiadiazolo[3,4-d]pyrimidine. The resulting compounds have anticoccidial activity and are useful in controlling cecal and/or intestinal coccidiosis when administered in minor quantities to animals, in particular to poultry usually in admixture with animal sustenance.

What is claimed is: 
     
       1. The process for the preparation of compounds having the structure: ##STR10## wherein X 1  and X 2  are independently halogen by reacting the compound having the structure: ##STR11## wherein X 1  and X 2  are as defined above with Raney nickel in aqueous-alcohol solvent at about room temperature to about 125° C. for a period of about 1 hour to 24 hours. .Iadd. 
     
     
       2.  The compound 9-(2-chloro-6-fluorobenzyl)adenine free of 3-position isomers such that said compound has a melting point of 245°-246° C.; a thin layer chromatogram on silica gel in chloroform-methanol (16:1) showing one spot with an Rf of 0.4; and a nuclear magnetic resonance spectrum in acetic acid-d4 of δ 5.70 (2 hydrogens-doublet), δ 7.35 (3 hydrogens-multiplet, and δ 8.15 (1 hydrogen-singlet)..Iaddend.