Abstract: New 2-[4-(diphenylmethyl)-1-piperazinyl]-acetic acids, their amides and their salts, processes for the preparation thereof and therapeutic compositions. These compounds have the formula ##STR1## wherein Y=--OH or --NH.sub.2 ; X and X'=H, halogen, alkoxy or trifluoromethyl; m=1 or 2 and n=1 or 2.The amides of the 2-[4-(diphenylmethyl)-1-piperazinyl]-acetic acids are prepared either by reacting a 1-(diphenylmethyl)-piperazine with an omegahaloacetamide, or by reacting an alkali metal salt of an omega-[4-(diphenylmethyl)-1-piperazinyl]-alkanol with a 2-haloacetamide, or yet by reacting ammonia with a halide or alkyl ester of a 2-[4-(diphenylmethyl)-1-piperazinyl]-acetic acid, whereas the 2-[4-(diphenylmethyl)-1-piperazinyl]-acetic acids are prepared by hydrolyzing the corresponding amide or lower alkyl ester.These compounds have in particular an antiallergic, spasmolytic and antihistaminic activity.

Abstract: A 1,3-disubstituted urea or 2-thiourea having the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.6, R.sub.7 and R.sub.8 represent independently a hydrogen atom, an alkyl radical containing 1 to 4 carbon atoms, an alkenyl radical containing 2 to 4 carbon atoms, an alkylene radical forming together with the carbon atom to which it is attached a cycloalkane ring having 5 or 6 carbon atoms, an aryl radical or a substituted aryl radical, R.sub.4 and R.sub.5 represent independently a hydrogen atom, an alkyl radical containing 1 or 2 carbon atoms or a phenyl radical, n and q are independently a whole number of from 3 to 7, m and p are independently 0, 1 or 2 and X is an oxygen or a sulfur atom, processes for the preparation thereof and pharmaceutical compositions containing the same.