Abstract: Compounds of formula (I): ##STR1## or a salt or acyl derivative thereof; whereinY is either --CH.dbd.N or ##STR2## R.sup.1 is hydroxy, halogen, (C.sub.1-4) alkyl, or (C.sub.1-4)alkoxy, R.sup.2 is a nitrogen-containing, basic substituent,R.sup.3 is hydrogen, hydroxy, halogen, (C.sub.1-4) alkyl, (C.sub.1-4) alkoxy or a nitrogen-containing, basic substituent, andR.sup.4 is hydrogen or hydroxy,are useful in treating diarrhoea and scours.

Abstract: A compound of formula (I): ##STR1## or a salt thereof wherein R.sup.1 is halogen, C.sub.1-4 alkyl or C.sub.1-4 alkoxyR.sup.2 is hydrogen, halogen, C.sub.1-4 alkyl or C.sub.1-4 alkoxyR.sup.3 and R.sup.4 are the same or different and each is hydrogen, C.sub.1-4 alkyl or acyl andR.sup.5 is either (i) ##STR2## wherein R.sup.6, R.sup.7 and R.sup.8 are the same or different and each is selected from hydrogen, halogen, alkyl, alkoxy, hydroxy, hydroxyalkyl, alkoxyalkyl, mercapto, mercaptoalkyl, amino, aminoalkyl, nitro, cyano, carboxy or a salt, ester or amide of carboxy provided that at least one of R.sup.6, R.sup.7 and R.sup.8 is other than hydrogen or (ii) ##STR3## wherein R.sup.9, R.sup.10 and R.sup.11 are the same or different and each is selected from hydrogen, halogen, alkyl, alkoxy, hydroxy, hydroxyalkyl, alkoxyalkyl, mercapto, mercaptoalkyl, amino, aminoalkyl, nitro, cyano, carboxy or a salt, ester or amide of carboxyand X is --CH.sub.2 -- or --CH.dbd.CH-- or (iii) ##STR4## wherein R.sup.12 and R.sup.

Abstract: Compounds of formula (I) ##STR1## and acid addition salts thereof, wherein R.sup.1 is hydrogen, hydroxy, alkoxy, aryloxy, aralkoxy, heteroaryloxy or heteroaralkoxy; andone of R.sup.2, R.sup.3 and R.sup.4 is hydrogen and the others are the same or different and each is hydrogen, alkyl, aryl, aralkyl, heteroaryl or heteroaralkyl; orR.sup.2 is hydrogen and ##STR2## is mono- or bi-cyclic amino, inhibit enterotoxin-induced secretion into the small intestine and are, therefore, useful in treating enterotoxin induced diarrhoea in humans and scours in animals.

Abstract: Compounds A--B--C wherein A is 2 imidazolinyl or N-alkyl derivative thereof, B is oxygen, sulphur, CR.sup.1 R.sup.2 wherein R.sup.1 and R.sup.2 are hydrogen or alkyl, or NR.sup.3 wherein R.sup.3 is hydrogen or alkyl, and C is a 5- or 6- membered carbo- or heterocyclic group having a nitrogen containing substituent and up to two other substituents, are useful in treatment of diarrhoea or scours. Certain compounds A--B--C are novel.

Abstract: Compounds of formula (I) ##STR1## and acid addition salts thereof, whereinR.sup.1 is hydrogen, hydroxy, alkoxy, aryloxy, aralkoxy, heteroaryloxy or heteroaralkoxy;andone of R.sup.2, R.sup.3 and R.sup.4 is hydrogen and the others are the same or different and each is hydrogen, alkyl, aryl, aralkyl, heteroaryl or heteroaralkyl;orR.sup.2 is hydrogen and ##STR2## is mono- or bi-cyclic amino, inhibit enterotoxin-induced secretion into the small intestine and are, therefore, useful in treating enterotoxin induced diarrhoea in humans and scours in animals.

Abstract: Vasoconstrictor .alpha.-adrenergic agonists of formula (I)A-B-C (I)wherein, A is a 2-imidazoline group or a guanidine group; B is a chemical bond or a linking group one or two atoms in length; and C is a C.sub.6-10 mono- or bi-cyclic group which is either an aromatic group, a heteroaromatic group containing only one hetero-atom, or a group containing an aromatic moiety; and which group C may be substituted by C.sub.1-4 alkyl, C.sub.1-4 alkoxy, halogen or hydroxyl; or salts thereof, are useful in the treatment and prevention of diarrhoea in livestock. Compositions of these compounds are described.

Abstract: Compounds of formula (I): ##STR1## wherein R.sup.1 and R.sup.2 are the same or different and each is selected from halogen, alkyl, haloalkyl, alkoxy and alkoxyalkyl,R.sup.3, R.sup.4 and R.sup.5 are the same or different and each is alkyl;n is 0,1,2 or 3; andZ is a pharmaceutically or veterinarily acceptable anion, protect animals from death due to enteropathogenic E. coli infection of the gastro-intestinal tract.

Abstract: Compounds A - B - C wherein A is 2 imidazolinyl or N-alkyl derivative thereof, B is oxygen, sulphur, CR.sup.1 R.sup.2 wherein R.sup.1 and R.sup.2 are hydrogen or alkyl, or NR.sup.3 wherein R.sup.3 is hydrogen or alkyl, and C is a 5 - or 6 - membered carbo- or heterocyclic group having a nitrogen containing substituent and up to two other substituents, are useful in treatment of diarrhoea or scours. Certain compounds A - B - C are novel.

Abstract: Vasoconstrictor .alpha.-adrenergic agonists of formula (I)A--B--C (I)wherein, A is a 2-imidazoline group or a guanidine group; B is a chemical bond or a linking group one or two atoms in length; and C is a C.sub.6-10 mono- or bi-cyclic group which is either an aromatic group, a heteroaromatic group containing only one hetero-atom, or a group containing an aromatic moiety; and which group C may be substituted by C.sub.1-4 alkyl, C.sub.1-4 alkoxy, halogen or hydroxyl; or salts thereof, are useful in the treatment and prevention of diarrhoea in livestock. Compositions of these compounds are described.