Thiophene derivatives and their pharmaceutical compositions and method of use

A compound of formula (I) ##STR24## and physiologically acceptable salts and hydrates thereof, in which one of R.sub.1 and R.sub.2 represents hydrogen, halogen or a C.sub.1-4 alkyl group which may be optionally substituted by hydroxy or C.sub.1-4 alkoxy, and the other represents the group R.sub.4 R.sub.5 Nalk- in which R.sub.4 represents hydrogen, C.sub.1-10 alkyl, C.sub.3-8 cycloalkyl, C.sub.3-6 alkenyl, C.sub.3-6 alkynyl, ar C.sub.1-6 alkyl wherein ar is phenyl or phenyl substituted with one or more C.sub.1-3 alkyl or C.sub.1-3 alkoxy groups or halogen atoms;

• heteroaralkyl wherein the heteroaryl portion is a furyl, thienyl, pyrrolyl, pyridinyl, pyrimidinyl, triazinyl, oxazolyl, triazolyl or thiazolyl ring which may be unsubstituted or substituted by C.sub.1-3 alkyl, C.sub.1-3 alkoxy, hydroxy, amino C.sub.1-6 alkyl, C.sub.1-6 alkylamino C.sub.1-6 alkyl, di C.sub.1-6 alkylamino C.sub.1-6 alkyl or halogen, and the alkyl portion of the heteroaralkyl group is a straight or branched C.sub.1-4 alkyl chain, and the heteroaryl ring is linked to the alkyl portion through a carbon or nitrogen atom;
• trifluoro C.sub.1-6 alkyl, or C.sub.1-6 alkyl substituted by hydroxy, C.sub.1-6 alkoxy, amino, C.sub.1-6 alkylamino, di C.sub.1-6 alkylamino or C.sub.3-8 cycloalkyl, and R.sub.5 represents hydrogen or a C.sub.1-4 alkyl group or R.sub.4 and R.sub.5 may, together with the nitrogen atom to which they are attached form a pyrrolidino, piperidino, hexamethylenimino, heptamethylenimino, tetrahydropyridino, morpholino or thiamorpholino group which may be unsubstituted or may be substituted by one or more C.sub.1-3 alkyl groups or a hydroxy group;
• Alk represents a straight or branched alkylene chain of 1 to 6 carbon atoms;
• R.sub.3, which may be in either the 2- or 3- position, represents the group ##STR25## where X represents --CH.sub.2 --, --O-- or --S--;
• n represents zero, 1 or 2;
• m represents 2, 3 or 4;
• and
• where Y represents S, O, CHNO.sub.2 or NR.sub.7 where R.sub.7 is nitro, cyano, C.sub.1-6 alkylsulphonyl or arylsulphonyl wherein aryl is phenyl or phenyl substituted with one or more C.sub.1-3 alkyl or C.sub.1-3 alkoxy groups or halogen atoms;
• R.sub.6 represents hydrogen, C.sub.1-6 alkyl, C.sub.3-6 alkenyl, C.sub.3-6 alkynyl, C.sub.1-6 alkoxy C.sub.1-6 alkyl or ar C.sub.1-6 alkyl, wherein ar is phenyl or phenyl substituted with one or more C.sub.1-3 alkyl or C.sub.1-3 alkoxy groups or halogen atoms;
• with the provisos that
• where R.sub.2 represents the group R.sub.4 R.sub.6 NAlk then R.sub.3 is in the 2- position;
• and
• where R.sub.2 represents hydrogen then R.sub.3 is in the 3-position.