| abstract |
The invention provides compounds of general formula <IMAGE> (I) and physiologically acceptable salts, hydrates and bioprecursors thereof, in which Y and Z, which may be the same or different, each represent oxygen, sulphur, =CHNO2 or =NR3 where R3 is hydrogen, nitro, cyano, lower alkyl, aryl, alkylsulphonyl or arylsulphonyl; p has a value from 2 to 12; R1 represents <IMAGE> in which R4 and R5 which may be the same or different, each represent hydrogen, lower alkyl, cycloalkyl, lower alkenyl, aralkyl or lower alkyl interrupted by an oxygen atom or a group >N-R6 in which R6 represents hydrogen or lower alkyl, or R4 and R5 together with the nitrogen atom to which they are attached form a 5 to 7-membered saturated heterocyclic ring which may contain an additional oxygen atom or the group >NR6; Q represents a furan or thiophen ring in which incorporation into the rest of the molecule is through bonds at the 2 and 5 positions, or a benzene ring in which incorporation into the rest of the molecule is through bonds at the 1 and 3 or 1 and 4 positions; X represents -CH2-, -O- or -S-; n represents zero or 1; m represents 2, 3 or 4 and Alk represents a straight chain alkylene group of 1 to 3 carbon atoms, and R2 represents lower alkyl or the group -(CH2)yE(CH2)xG in which y represents 2, 3 or 4 or can additionally represent zero or 1 when E is a -CH2- group, x represents zero, 1 or 2; E represents -CH2-, -O- or -S-; and G represents a monocyclic 5 or 6 membered carbocyclic or heterocyclic aromatic ring, or G represents the group <IMAGE> where Q' represents any of the rings defined for Q; Alk' represents any of the groups defined for Alk; and R4' and R5' which may be the same or different represent any of the groups defined for R4 or R5. The compounds of formula (I) have pharmacological activity as selective histamine H2-antagonists. |