Thiophene compounds

A thiophene compound selected from those of formula I:

• ##STR8## in which:
• each of X and Y, which are the same or different, are selected from the group consisting of hydrogen, halogen, alkyl and alkoxy each having 1 to 5 carbon atoms inclusive in straight or branched chains, and dialkylamino in which each alkyl contains 1 to 5 carbon atoms inclusive in straight or branched chains;
• n is selected from integers 2 to 5 inclusive;
• m is selected from zero, one and two;
• R is selected from the group consisting of hydrogen and alkyl having from 1 to 5 carbon atoms inclusive in straight or branched chains;
• and
• R' is selected from the group consisting of alkyl having from 1 to 5 carbon atoms inclusive in straight or branched chains, or alternatively
• R and R' together with the nitrogen to which they are bonded (viz the group ##STR9## as a whole is selected from the group consisting of:
• unsubstituted pentagonal and hexagonal heterocycles each selected from those containing one nitrogen, one nitrogen and one oxygen, and two nitrogen, and these heterocycles substituted by a substituent selected from the group consisting of:
• straight or branched (C.sub.1 -C.sub.5) alkyl and unsubstituted, mono- and poly- substituted arylalkyl in which the alkyl moiety contains 1 to 5 carbon atoms inclusive in straight or branched chains, and the substituent(s) on the aryl moiety is selected from the group consisting of:
• halogen, straight and branched (C.sub.1 -C.sub.5) alkyl, and straight and branched (C.sub.1 -C.sub.5) alkoxy;
• and,
• the corresponding enantiomers, and
• their addition salts with physiologically-tolerable acids.