The invention relates to a novel herbicide composition, which comprises the (S) enantiomer or racemate of a compound of the general formula (I), ##STR1## wherein R stands for a methyl or ethyl group, as active ingredient in an amount of 0.01 to 95% by weight together with one or more solid and/or liquid carrier(s), preferably grist(s) of native or synthetic material(s) and/or with inert solvents(s), preferably xylene(s) and/or cyclohexanone; and optionally with surface active agents(s), preferably anionic and/or nonionic emulsifying or dispersing agent(s). The invention further relates to the above compounds of the general formula (I) as well as to a process for the preparation thereof. The compounds according to the invention possess an outstanding herbicidal effect (over 90%) and advantageous selectivity threshold values against cultivated plants.