Patent GB-803201-A (GB)
Title: New phenthiazine dithiocarboxylates and processes for their preparation
IPC: C07D219/16
Filed: 1957-01-11
Abstract: The invention comprises phenthiazine dithiocarboxylates of the general formula (I) <FORM:0803201/IV (b)/1> and their acid addition and quaternary ammonium salts, wherein X and Y are hydrogen or halogen atoms or alkoxy or alkylthio groups, A is a saturated straight or branched chain divalent aliphatic hydrocarbon group containing 2 to 5 carbon atoms, unsubstituted or substituted by a group <FORM:0803201/IV (b)/2> B being a single bond or -CH2-, and R1 and R2 are the same or different alkyl groups containing not more than 4 carbon atoms or form with the adjacent nitrogen atom a heterocyclic group, or R1 together with the adjacent nitrogen atom forms with the whole or part of A or B, when -CH2-, a heterocyclic group and R2 is a hydrogen atom or an alkyl group), and a process for the manufacture thereof by reacting a phenthiazine-10-dithiocarboxylate of the general formula (II) <FORM:0803201/IV (b)/3> (wherein M is an alkali metal atom) with an aminoalkyl halide of the general formula (III) <FORM:0803201/IV (b)/4> (wherein Hal represents a halogen atom).  The reaction is preferably carried out in an inert organic solvent medium such as ether, benzene, toluene, xylene or dimethyl-formamide using the aminoalkyl halide in the form of the free base; using the latter as an acid addition salt necessitates the addition of an excess of an alkaline condensing agent.  The metal derivatives (II) may be prepared by the action of carbon disulphide on an alkali metal derivative of a phenthiazine of general formula IV <FORM:0803201/IV (b)/5> in an inert solvent medium; preferably the formation of the alkali metal phenthiazine derivative (IV), its conversion to the phenthiazine-10-dithiocarboxylate (II) and subsequent reaction of the latter with the aminoalkyl halide (III) is carried out in the same organic solvent without isolation of the various intermediates.  The final products are isolated as bases, acid addition salts or quaternary ammonium derivatives.  Examples describe the preparation of diethylaminoethyl phenthiazine-10-dithiocarboxylate (and its hydrochloride, methiodide and ethiodide), dimethylaminoethyl phenthiazine - 10 - dithiocarboxylate, 3 - dimethylaminopropyl phenthiazine - 10 - dithiocarboxylate (and its hydrochloride), 3-diethylaminopropyl phenthiazine - 10 - dithiocarboxylate (and its picrate), 2-piperidinoethyl phenthiazine - 10 - dithiocarboxylate, 2 - morpholinoethyl phenthiazine - 10 - dithiocarboxylate (and its hydrochloride), 2-(4-ethylpiperazinyl)-ethyl phenthiazine - 10 - dithiocarboxylate (and its dimethiodide), 1:3 - bis - dimethylamino - 2 - propyl and 2:3 - bis - dimethylaminopropyl phenthiazine - 10 - dithiocarboxylates, 3 - diethylamino - 2 - methylpropyl phenthiazine - 10-dithiocarboxylate hydrochloride and methiodide, (1 - ethyl - 2 - piperidyl) - methyl phenthiazine - 10 - dithiocarboxylate, 1 - ethyl - 2 - methyl - 3 - piperidyl phenthiazine - 10 - dithiocarboxylate hydrochloride, 1:3 - bis - piperidino - 2 - propyl and 2:3 - bis - piperidino - propyl phenthiazine - 10 - dithiocarboxylates, diethylaminoethyl 3 - chlorophenthiazine - 10 - dithiocarboxylate (and its hydrochloride), diethylaminoethyl 3-methoxyphenthiazine-10-dithiocaboxylate (and its hydrochloride), diethylaminoethyl 3-methylthiophenthiazine-10-dithiocarboxylate, 2 - diethylamino - 1 - propyl and 1 - diethylamino - 2 - propyl phenthiazine-10-dithiocarboxylates and 1 - ethyl - 3 - piperidyl phenthiazine - 10 - dithiocarboxylate (and its hydrochloride). Lithium phenthiazine-10-dithiocarboxylate is prepared by the action of carbon disulphide on the lithium derivative of phenthiazine in ether.