First functionalization by metallation of the pyridine moiety of 4-methoxypyridopyrimidines.: Diazines:: Part 38

Starting from pyridopyrimidin-4(3H)-ones, a general synthetic route leading to 4-methoxypyridopyrimidines is described. The first lithiation and functionalization of the pyridine moiety has been studied. According to various structural parameters, the regioselectivity of the metallation is discussed. The functionalization of the 4-methoxypyridopyrimidines via the metallation reaction, provides an efficient process to access new substituted pyridopyrimidines. (C) 2004 Elsevier Ltd. All rights reserved.