Automatic composition of music of grammatical evolution

Disclosed are selected amino ester derivatives of 3-trihalomethyl-1,2,4-thiadiazole compounds of the formula: wherein R1 is a CCl3 or CF3 group; R2 is a hydrogen or a lower alkyl group of 1 to 4 carbon atoms; x is from 1 to 4; and y is from 1 to 5. These compounds are shown to have herbicidal properties.