The invention comprises aminoanthrapyrimidines of the formula:- &lt;FORM:0876719/IV (b)/1&gt; wherein R1 stands for hydrogen or an acyl radical or wherein R1 stands for a radical of the formula:- &lt;FORM:0876719/IV (b)/2&gt; wherein R2 and R3, which may be the same or different, stand for alkyl radicals and R4 stands for an alkylene radical, and wherein the benzene ring A may optionally be substituted by halogen atoms or by alkyl or alkoxy radicals of not more than 5 carbon atoms, and the acid addition salts thereof, provided that when R1 stands for hydrogen, benzene ring A bears an alkyl or alkoxy substituent of not more than 5 carbon atoms or a halogen substituent which is not a 4-bromo substituent, and when R1 stands for the benzoyl radical benzene ring A bears a halogen substituent or an alkyl or alkoxy substituent of not more than 5 carbon atoms; the preparation thereof by (a) reacting the corresponding 1-amino anthraquinone with cyanamide or a derivative thereof in the presence of hydrogen chloride or (b) interaction of the corresponding 2-halogenoanthrapyrimidine with an amino compound of the formula:- &lt;FORM:0876719/IV (b)/3&gt; where R2, R3 and R4 have the meanings stated above; also pharmaceutical compositions containing these and similar compounds (see Group VI).  Specified solvents for process (a) are nitrobenzene and for process (b) chlorobenzene.  Specified compounds are:-2-amino-4-methyl-, 2-(3-diethylaminopropylamino)-, 2-benzoylamino-6-chloro-, 2-amino-6-chloro- and 2-amino-6-methoxy-anthrapyrimidine.ALSO:A trichomonacticidal composition for oral and topical administration comprises as active ingredient one or more anthrapyrimidines of the formula &lt;FORM:0876719/VI/1&gt; wherein R is an amino group optionally substituted by acyl or dialkylaminoalkyl radicals, and wherein the benzene ring A may optionally be substituted by alkyl or alkoxy radicals of not more than 5 carbon atoms or by halogen atoms or an acid addition salt thereof or admixture with a non-toxic pharmaceutically acceptable carrier.  R may be an acylamino radical, e.g. the benzoylamino or stearoylamino radical, a dialkylamino alkyl amino radical e.g. the 3-diethylamino propylamino radical or the p-toluenesulphonylamino radical.  Topical forms specified are pessaries, jellies, ointments, and vaginal tablets.  The pessary is formed from a liquid or low-melting point pessary base which may be theobroma oil, gelatine, one or more fatty acids or one or more polyethylene glycols of average molecular weight between 1000 and 4000.  The jellies are in the form of aqueous colloidal solutions prepared from gelatine, a cellulose derivative, e.g. sodium carboxymethyl cellulose, methyl cellulose, ethyl cellulose or methyl ethyl cellulose, natural gum, e.g. tragacanth or an alginate.  They may also contain dispersing agents, e.g. the condensation products and fatty alcohols, e.g. cetyl alcohols with ethylene oxide and humectants, e.g. glycerol.  The ointments are oil in water or water in oil emulsions prepared from mineral or vegetable oils or mixtures thereof, or from one or more polyethylene glycols.  The vaginal or oral tablets are formed with diluents such as glucose or lactose, binding agents, e.g. gum acacia, disintegrating agents, e.g. starch and lubricating agents, e.g. magnesium stearate.  The oral tablets may be coated with materials such as sucrose, shellac or cellulose acetate hydrogen phthalate.  The composition is also administered orally as aqueous suspensions using suspending agents such as sodium carboxy methyl cellulose, dispersing agents as above, sweetening agents, e.g. sucrose or saccharin, colouring, flavouring and preserving agents, e.g. methyl or n-propyl paraben.  The compositions may contain additional therapeutic agents for the control of intercurrent infections, e.g. nyartatin.  Specified active ingredients are: 2-amino, 2-benzoylamino, 2-(3 - diethylaminopropylamino), 2 - amino - 4 - amino-6-chloro and 2-amino-6-chloro anthrapyrimidine.  The Provisional Specification refers to anthrapyrimidines in which the second benzene ring is substituted.