Abstract: The invention relates to a process for the preparation of ranitidine of formula (I) ##STR1## which comprises reacting a thiol of formula (II) ##STR2## with an alkylating agent of formula (III) ##STR3## where L is a leaving group, preferably halogen. The invention also relates to novel intermediates, the thiol of formula (II) ##STR4## in the form of a stable acid addition salt, and the isothiourea of formula (IV) ##STR5## and stable acid additions salts thereof.

Abstract: The invention provides compounds of the general formula (I) ##STR1## and physiologically acceptable salts, hydrates and bioprecursors thereof, in whichR.sub.1 and R.sub.2, which may be the same or different, each represent hydrogen, C.sub.1-10 alkyl, cycloalkyl, alkenyl, aralkyl, trifluoroalkyl, heteroaralkyl, or alkyl substituted by hydroxy, alkoxy, amino, alkylamino, dialkyamino or cycloalkyl, or R.sub.1 and R.sub.2 may together with the nitrogen atom to which they are attached form a 5 to 10 membered ring which may be saturated or may contain at least one double bond, may be unsubstituted or may be substituted by one or more C.sub.1-3 alkyl groups, or a hydroxy group and/or may contain another heteroatom selected from oxygen and sulphur;Alk represents a straight or branched alkylene chain of 1 to 6 carbon atoms and is attached to the cyclohexadiene ring at either the 4- or 5- position;X represents --CH.sub.2 or --O--;m represents 2, 3, 4 or 5 and when X is --O-- the chain (CH.sub.2).sub.

Abstract: Ranitidine is prepared by reacting a compound of formula (II) ##STR1## with aziridine. The reaction may be carried out in the absence of a solvent or preferably in the presence of a solvent such as water or an alkanol at elevated temperature.

Abstract: Ranitidine is prepared by treating an aldehyde of formula (II) ##STR1## with dimethylamine and a reducing agent which is capable of effecting reductive alkylation to introduce the group Me.sub.2 NCH.sub.2 -- but which does not reduce the nitroethene group. The reaction is carried out in a suitable solvent, preferably in the presence of an acid or followed by treatment with an acid. Suitable reducing agents include, diborane, aluminium hydride and alkali or alkaline earth metal borohydrides.The aldehyde (II) may be generated in situ from an acetal of formula (III) ##STR2## where R.sub.1 and R.sub.2 are both alkyl groups or R.sub.1 OCHOR.sub.2 forms a cyclic acetal.

Abstract: Ranitidine is prepared by reacting cystamine of formula (II) ##STR1## either with a nitroethenamine of formula (III) ##STR2## where L is a leaving group such as alkylthio, e.g. methylthio, or with a compound of formula (IV) ##STR3## where L is a leaving group as defined above, followed by reaction with methylamine, to give a disulphide of formula (V) ##STR4## which is then reacted with 5-[(dimethylamino)methyl]-2-furanmethanol under acid conditions.

Abstract: The invention provides compounds of the general formula (I) ##STR1## and physiologically acceptable salts, hydrates and bioprecursors 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, cycloalkyl, alkenyl, alkynyl, aralkyl, heteroaralkyl, trifluoroalkyl, or alkyl substituted by hydroxy, alkoxy, amino, alkylamino, dialkylamino or 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 5 to 10 membered ring which may be saturated or may contain at least one double bond, may be unsubstituted or may be substituted by one or more C.sub.

Abstract: The invention provides compounds of general formula ##STR1## and physiologically acceptable salts, hydrates and bioprecursors thereof, in whichY and Z, which may be the same or different, each represent oxygen, sulphur, .dbd.CHNO.sub.2 or .dbd.NR.sub.3 where R.sub.3 is hydrogen, nitro, cyano, lower alkyl, aryl, alkylsulphonyl or arylsulphonyl;p has a value from 2 to 12;R.sub.1 represents ##STR2## in which R.sub.4 and R.sub.5 which may be the same or different, each represent hydrogen, lower alkyl, cycloalkyl, lower alkenyl, aralkyl or lower alkyl interrupted by an oxygen atom or a group >N-R.sub.6 in which R.sub.6 represents hydrogen or lower alkyl, or R.sub.4 and R.sub.5 together with the nitrogen atom to which they are attached from a 5 to 7-membered saturated heterocyclic ring which may contain an additional oxygen atom or the group >NR.sub.

Abstract: The invention relates to compounds of the general formula (I) ##STR1## and physiologically acceptable salts, hydrates and bioprecursors thereof, in whichR.sub.1 and R.sub.2, which may be the same of different, each represent hydrogen, C.sub.1 alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, trifluoroalkyl, or alkyl substituted by hydroxy, alkoxy, amino alkylamino dialkylamino or cycloalkyl or R.sub.1 and R.sub.2 may together with the nitrogen atom to which they are attached form a 5 to 10 membered ring which may be saturated or may contain at least one double bond, may be unsubstituted or may be substituted by one or more C.sub.1-3 alkyl groups or a hydroxy group and/or may contain another heteroatom which is oxygen or sulphur;Alk represents a straight or branched alkylene chain of 1 to 6 carbon atoms,Q represents a furan or thiophene ring in which incorporation into the rest of the molecule is through bonds at the 2- and 5- positions, the furan ring optionally bearing a further substituent R.sub.

Abstract: The invention relates to compounds of the formula (I) ##STR1## and physiologically acceptable salts, hydrates and bioprecursors thereof, in whichR.sub.1 and R.sub.2 represent hydrogen, an aliphatic or cycloaliphatic group, or R.sub.1 and R.sub.2 together with the nitrogen atom form a 5 to 10 membered heterocyclic ring:Alk represents a straight or branched alkylene chain;Q represents furan, thiophen or benzene ring which is incorporated into the rest of the molecule;X represents --CH.sub.2 --, ##STR2## --O-- or --S-- whereR.sub.6 represents hydrogen or methyl;n represents zero, 1 or 2;m represents 2, 3 or 4;R.sub.3 represents hydrogen, a substituted or unsubstituted aliphatic or aryl group and;R.sub.4 and R.sub.5, which may be the same or different, each represent hydrogen, a substituted or unsubstituted aliphatic, aryl, or together with the nitrogen atom form a heterocyclic group.

Abstract: The invention provides compounds of general formula ##STR1## and physiologically acceptable salts, hydrates and bioprecursors thereof, in whichY and Z, which may be the same or different, each represent oxygen, sulphur, .dbd.CHNO.sub.2 or .dbd.NR.sub.3 where R.sub.3 is hydrogen, nitro, cyano, lower alkyl, aryl, alkylsulphonyl or arylsulphonyl;p has a value from 2 to 12;R.sub.1 represents ##STR2## in which R.sub.4 and R.sub.5 which may be the same or different, each represent hydrogen, lower alkyl, cycloalkyl, lower alkenyl, aralkyl or lower alkyl interrupted by an oxygen atom or a group >N-R.sub.6 in which R.sub.6 represents hydrogen or lower alkyl, or R.sub.4 and R.sub.5 together with the nitrogen atom to which they are attached form a 5 to 7-membered saturated heterocyclic ring which may contain an additional oxygen atom or the group >NR.sub.

Abstract: The invention relates to compounds of the general formula (I) ##STR1## and physiologically acceptable salts, N-oxides, hydrates and bioprecursors thereof,in which Y represents .dbd.O, .dbd.S, .dbd.CHNO.sub.2 or .dbd.NR.sub.3 where R.sub.3 represents hydrogen, nitro, cyano, lower alkyl, aryl, lower alkylsulphonyl or arylsulphonyl;R.sub.1 and R.sub.2, which may be the same or different, each represent hydrogen lower alkyl, cycloalkyl, lower alkenyl, aralkyl, hydroxy, lower trifluoroalkyl, lower alkyl substituted by hydroxy, lower alkoxy, amine, lower alkylamino or dialkylamino, or R.sub.1 and R.sub.2 together with the nitrogen atom to which they are attached form a 5 to 7 membered heterocyclic ring which may contain other heteroatoms or the group ##STR2## where R.sub.

Abstract: The invention relates to compounds of the general formula ##STR1## and physiologically acceptable salts and N-oxides, hydrates and bioprecursors thereof, in which R.sub.1 and R.sub.2 which may be the same or different each represent hydrogen, C.sub.1-8 alkyl, C.sub.4-8 cycloalkyl, C.sub.3-6 alkenyl, aralkyl with 1 to 4 carbon atoms in the alkyl residue or C.sub.1-8 alkyl interrupted by an oxygen atom or a group ##STR2## in which R.sub.5 represents hydrogen or C.sub.1-8 alkyl, or R.sub.1 and R.sub.2 may together with the nitrogen atom to which they are attached, form a saturated monocyclic 5 to 7 membered heterocyclic ring which may additionally contain the heterofunction O or ##STR3## R.sub.3 represents straight or branched chain C.sub.1-8 alkyl, alkoxyalkyl with 1 to 8 carbon atoms in each alkyl residue, C.sub.1-8 hydroxyalkyl, C.sub.1-8 alkoxycarbonyl, alkyl thioalkyl with 1 to 8 carbon atoms in each alkyl residue, halogen or aryl;R.sub.4 represents hydrogen, C.sub.1-8 alkyl, C.sub.

Abstract: Compounds of the general formula I: ##STR1## and physiologically acceptable salts thereof and N-oxides and hydrates, in which R.sub.1 and R.sub.2 which may be the same or different represent hydrogen, lower alkyl, cycloalkyl, lower alkenyl, aralkyl or lower alkyl interrupted by an oxygen atom or a group ##STR2## in which R.sub.4 represents hydrogen or lower alkyl or R.sub.1 and R.sub.2 may, together with the nitrogen atom to which they are attached, form a heterocyclic ring which may contain other heteroatoms selected from O and ##STR3## R.sub.3 is hydrogen, lower alkyl, lower alkenyl or alkoxyalkyl; X is --CH.sub.2 --, O or S;Y represents .dbd.S, .dbd.O, .dbd.NR.sub.5 or .dbd.CHR.sub.6 ;Alk denotes a straight or branched alkylene chain of 1 to 6 carbon atoms;R.sub.5 is H, nitro, cyano, lower alkyl, aryl, alkylsulphonyl, or arylsulphonyl;R.sub.6 represents nitro, arylsulphonyl or alkylsulphonyl;m is an integer from 2 to 4; andn is 1 or 2; or when X.dbd.S, or --CH.sub.2 --, n is zero, 1 or 2.

Abstract: The invention relates to compounds of the general formula (I) ##STR1## and physiologically acceptable salts, N-oxides, hydrates and bioprecursors thereof, in which Y represents .dbd.O, .dbd.S, .dbd.CHNO.sub.2 or .dbd.NR.sub.3 where R.sub.3 represents hydrogen, nitro, cyano, lower alkyl, aryl, lower alkylsulphonyl or arylsulphonyl; R.sub.1 and R.sub.2, which may be the same or different, each represent hydrogen lower alkyl, cycloalkyl, lower alkenyl, aralkyl, hydroxy, lower trifluoroalkyl, lower alkyl substituted by hydroxy, lower alkoxy, amine, lower alkylamino or dialkylamino, or R.sub.1 and R.sub.2 together with the nitrogen atom to which they are attached form a 5 to 7 membered heterocyclic ring which may contain other heteroatoms or the group ##STR2## where R.sub.

Abstract: The invention provides compounds of general formula ##STR1## and physiologically acceptable salts, hydrates and bioprecursors thereof, in whichY and Z, which may be the same or different, each represent oxygen, sulphur, =CHNO.sub.2 or =NR.sub.3 where R.sub.3 is hydrogen, nitro, cyano, lower alkyl, aryl, alkylsulphonyl or arylsulphonyl;p has a value from 2 to 12;R.sub.1 represents ##STR2## in which R.sub.4 and R.sub.5 which may be the same or different, each represent hydrogen, lower alkyl, cycloalkyl, lower alkenyl, aralkyl or lower alkyl interrupted by an oxygen atom or a group >N-R.sub.6 in which R.sub.6 represents hydrogen or lower alkyl, or R.sub.4 and R.sub.5 together with the nitrogen atom to which they are attached form a 5 to 7-membered saturated heterocyclic ring which may contain an additional oxygen atom or the group >NR.sub.

Abstract: Compounds of the general formula I: ##STR1## and physiologically acceptable salts thereof and N-oxides and hydrates, in which R.sub.1 and R.sub.2 which may be the same or different represent hydrogen, lower alkyl, cycloalkyl, lower alkenyl, aralkyl or lower alkyl interrupted by an oxygen atom or a group ##STR2## in which R.sub.4 represents hydrogen or lower alkyl or R.sub.1 and R.sub.2 may, together with the nitrogen atom to which they are attached, form a heterocyclic ring which may contain other heteroatoms selected from O and ##STR3## R.sub.3 is hydrogen, lower alkyl, lower alkenyl or alkoxyalkyl; X is --CH.sub.2 --, O-- or --S--;Y represents .dbd.S, .dbd.O, .dbd.NR.sub.5 or .dbd.CHR.sub.6 ;Alk denotes a straight or branched alkylene chain of 1 to 6 carbon atoms;R.sub.5 is H, nitro, cyano, lower alkyl, aryl, alkylsulphonyl, or arylsulphonyl;R.sub.6 represents nitro, arylsulphonyl or alkylsulphonyl;m is an integer from 2 to 4; andn is 1 or 2; or when X is --S-- or --CH.sub.2 --, n is zero, 1 or 2.

Abstract: Compounds of the general formula ##STR1## and physiologically acceptable salts, hydrates and bioprecursors thereof are disclosed, in whichR.sub.1 and R.sub.2, which may be the same or different, represent hydrogen, lower alkyl, cycloalkyl, aralkyl or lower alkenyl groups, which alkyl groups may be interrupted by an oxygen atom or a group ##STR2## in which R.sub.4 represents hydrogen or lower alkyl; or R.sub.1 and R.sub.2 may, together with the nitrogen atom to which they are attached form a heterocyclic ring which may contain other hetero functions selected from --O-- and ##STR3## R.sub.3 represents hydrogen, lower alkyl, lower alkenyl or alkoxyalkyl; X represents --O--, --S-- or --CH.sub.2 --;Y represents .dbd.S, .dbd.O, .dbd.NR.sub.5 or .dbd.CHR.sub.6 ;in which R.sub.5 is hydrogen, nitro, cyano, lower alkyl, aryl, alkylsulphonyl or arylsulphonyl and R.sub.6 represents nitro, alkylsulphonyl or arylsulphonyl;m is an integer from 2 to 4 inclusive;n is 1 or 2 or, when X is S or CH.sub.

Abstract: The invention relates to compounds of the general formula (I) ##STR1## and physiologically acceptable salts, N-oxides, hydrates and bioprecursors thereof, in whichY represents .dbd.O, .dbd.S, .dbd.CHNO.sub.2 or .dbd.NR.sub.3 where R.sub.3 represents hydrogen, nitro, cyano, lower alkyl, aryl, lower alkylsulphonyl or arylsulphonyl;R.sub.1 and R.sub.2, which may be the same or different, each represent hydrogen lower alkyl, cycloalkyl, lower alkenyl, aralkyl, hydroxy, lower trifluoroalkyl, lower alkyl substituted by hydroxy, lower alkoxy, amine, lower alkylamino or dialkylamino, or R.sub.1 and R.sub.2 together with the nitrogen atom to which they are attached form a 5 to 7 membered heterocyclic ring which may contain other heteroatoms or the group ##STR2## where R.sub.

Abstract: Compounds of the general formula: ##STR1## in which R.sub.3 is hydrogen, lower alkyl, lower alkenyl or alkoxyalkyl. These compounds are useful in the preparation of novel aminoalkyl furan derivatives having a selective action on histamine receptors.

Abstract: Compounds of the general formula I: ##STR1## and physiologically acceptable salts thereof and N-oxides and hydrates, in which R.sub.1 and R.sub.2 which may be the same or different represent hydrogen, lower alkyl, cycloalkyl, lower alkenyl, aralkyl or lower alkyl interrupted by an oxygen atom or a group ##STR2## in which R.sub.4 represents hydrogen or lower alkyl or R.sub.1 and R.sub.2 may, together with the nitrogen atom to which they are attached, form a heterocyclic ring which may contain other heteroatoms selected from O and ##STR3## R.sub.3 is hydrogen, lower alkyl, lower alkenyl or alkoxyalkyl; X is --CH.sub.2 --, O or S;Y represents .dbd. S, .dbd. O, .dbd. NR.sub.5 or .dbd. CHR.sub.6 ;Alk denotes a straight or branched alkylene chain of 1 to 6 carbon atoms;R.sub.5 is H, nitro, cyano, lower alkyl, aryl, alkylsulphonyl, or arylsulphonyl;R.sub.6 represents nitro, arylsulphonyl or alkylsulphonyl;M is an integer from 2 to 4; andN is 1 or 2; or when X .dbd. S, or --CH.sub.2 --, n is zero, 1 or 2.