PYRIMIDINE DERIVATIVES APROCESS FOR THEIR PREPARATION AND COMPOSITIONS CONTAINING THEM AND THEIR USE AS HISTAMINE H1-ANTAGONISTS

摘要

The present invention provides compounds of formula (2):- and their pharmaceutically acceptable salts which are useful as histamine H1- antagonists. In formula (2) R<1> is halogen or nitro; R<2> is C1-4 alkyl; R<3> is a C1-3 alkylene group; and R<4> is 3-pyridyl; N-oxo-3-pyridyl; 6-methyl-3-pyridyl; N-oxo- 6-methyl-3-pyridyl; 6-hydroxymethyl-3-pyridyl; 4,6-dimethyl-3-pyridyl; N-oxo- 4,6-dimethyl-3-pyridyl; 6-hydroxymethyl-4-methyl-3-pyridyl; 5,6-dimethyl-3- pyridyl; N-oxo-5,6-dimethyl-3-pyridyl; 6-hydroxymethyl-5-methyl-3-pyridyl; 4- pyridyl or N-oxo-4-pyrid