Antisecretory guanidine derivatives and pharmaceutical compositions containing them

A guanidine derivative of the formula I:

• Het.sup.1 -(CH.sub.2).sub.m -Y.sup.1 -(CH.sub.2).sub.n -NR.sup.1 -A-NR.sup.2 -(CH.sub.2).sub.q -Y.sup.2 -(CH.sub.2).sub.p -Het.sup.2I
• in which
• Y.sup.1 and Y.sup.2, which may be the same or different, are oxygen or sulphur atoms, direct bonds or methylene or sulphinyl radicals;
• m and p, which may be the same or different, are 0 to 4 and
• n and q, which may be the same or different, are 1 to 4,
• provided that when Y.sup.1 or Y.sup.2 is an oxygen or sulphur atom or a sulphinyl radical, m or p respectively is 1 to 4 and provided that when Y.sup.1 or Y.sup.2 is an oxygen atom or a sulphinyl radical, n or q respectively is 2 to 4;
• one of R.sup.1 and R.sup.2 is a hydrogen atom and the other is a hydrogen atom or an alkyl radical of 1 to 6 carbon atoms;
• A is a 3,4-dioxocyclobuten-1,2-diyl radical or a radical of the formula C.dbd.Z in which Z is a sulphur or oxygen atom or a radical of the formula NCN, NNO.sub.2, CHNO.sub.2, NCONH.sub.2, C(CN).sub.2, NCOR.sup.3, NCO.sub.2 R.sup.3, NSO.sub.2 R.sup.3 or NR.sup.4 in which R.sup.3 is an alkyl radical of 1 to 6 carbon atoms, an aryl radical of 6 to 12 carbon atoms or an alkylphenyl radical of 7 to 12 carbon atoms and R.sup.4 is a hydrogen atom or an alkyl radical of 1 to 6 carbon atoms;
• or when R.sup.1 and R.sup.2 are both hydrogen atoms -A- represents a radical of the formula II:
• -A.sup.1 -E.sup.1 -G-E.sup.2 -A.sup.2 - II
• in which A.sup.1 and A.sup.2, which may be the same or different, are 3,4-dioxocyclobuten-1,2-diyl radicals or radicals of the formula C.dbd.Z.sup.1 and C.dbd.Z.sup.2 respectively in which Z.sup.1 and Z.sup.2, which may be the same or different, have one of the values given above for Z;
• E.sup.1 and E.sup.2, which may be the same or different, are oxygen or sulphur atoms or NH radicals optionally substituted by alkyl radicals of 1 to 10 carbon atoms, alkenyl or alkynyl radicals of 3 to 10 carbon atoms in which the double or triple bond respectively is separated from the nitrogen atom to which the radical is attached by at least one carbon atom, cycloalkyl radicals of 3 to 8 carbon atoms, (primary hydroxy)alkyl radicals of 2 to 6 carbon atoms, alkoxyalkyl radicals of 3 to 10 carbon atoms in which the oxygen atom is separated from the nitrogen atom to which the radical is attached by at least two carbon atoms, or alkylamino or dialkylamino radicals of 3to 10 and 4 to 10 carbon atoms respectively in which the nitrogen atom is separated from the nitrogen atom to which the radical is attached by at least two carbon atoms;
• and G is an alkylene radical of 2 to 12 carbon atoms, an alkenylene or alkylene radical of 4 to 12 carbon atoms in which the double and triple bonds respectively are separated from E.sup.1 and E.sup.2 by at least one carbon atom, or a hydroxyalkylene radical of 3 to 12 carbon atoms in which the hydroxy substituent is carried on a carbon atom which is separated from E.sup.1 and E.sup.2 by at least one carbon atom;
• Het.sup.1 is an oxazol-4-yl, thiazol-4-yl or imidazol-4-yl radical substituted in the 2-position by a radical of the formula III:
• ##STR6## or Het.sup.1 is a 1,2,4-thiadiazol-3-yl or 1,2,4-oxadiazol-3-yl radical substituted in the 5-position by a radical of the formula III, in which R.sup.5 is a hydrogen atom, an alkyl radical of 1 to 10 carbon atoms, an alkanoyl radical of 1 to 6 carbon atoms or an aroyl radical of 7 to 11 carbon atoms;
• Het.sup.2 is independently one of the values given above for Het.sup.1 ;
• provided that when R.sup.1 and R.sup.2 are both hydrogen atoms and A is C.dbd.NH, Y.sup.1 and/or Y.sup.2 is a sulphur atom;
• and the pharmaceutically-acceptable acid-addition salts thereof.