Pharmacologically active guanidine compounds

A compound of the formula:

• ##SPC10##
• wherein A is such that there is formed together with the carbon atom shown an unsaturated heterocyclic nucleus, said unsaturated heterocyclic nucleus being an imidazole, pyrazole, pyrimidine, pyrazine or pyridazine ring;
• X.sub.1 is hydrogen, lower alkyl, hydroxy, trifluoromethyl, benzyl, halogen, amino or ##EQU6## in which E' is NH or N-cyano;
• X.sub.2 is hydrogen or when X.sub.1 is lower alkyl, lower alkyl or halogen;
• k is 0 to 2 and m is 2 or 3, provided that the sum of k and m is 3 or 4;
• Y is oxygen, sulphur or NH;
• E is NR.sub.2 ;
• R.sub.1 is hydrogen, lower alkyl or di-lower alkylamino-lower alkyl;
• and R.sub.2 is hydrogen, nitro or cyano, or a pharmaceutically acceptable addition salt thereof with the proviso that X.sub.1 is ##EQU7## only when E is NH or N-cyano.