5-Methylthiopyrimidine derivatives, their preparation process and fungicides containing same as active ingredients

A 5-methylthiopyrimidine derivative represented by the following formula (I):

• ##STR46## wherein R.sup.1 is a methyl group, R.sup.2 is a propargyl or allyl group, and X is an oxygen atom.

An agricultural and horticultural fungicidal composition comprising, a carrier and/or an adjuvant and, as an active ingredient, a fungicidally effective amount of a 5-methylthiopyrimidine derivative represented by the following formula (I):

• ##STR47## wherein R.sup.1 means an alkyl group having 1-6 carbon atoms or a phenyl, benzyl, alkenyl or alkoxyalkyl group, R.sup.2 denotes an alkyl group having 1-6 carbon atoms, a phenyl, halogen-substituted phenyl, alkenyl, .omega.-phenyl-substituted alkenyl, alkynyl, alkoxyalkyl, alkoxyalkoxyalkyl, alkylthioalkyl, aminoalkyl, alkoxycarbonylalkyl, aminocarbonylalkyl, furfuryl, thienylmethyl or tetrahydrofuryl group of a ##STR48## in which R.sup.3 and R.sup.4 are individually a hydrogen atom or methyl group, Y means a hydrogen or halogen atom or a methyl or methoxy group, and n stands for an integer of 1 or 2, and X denotes an oxygen or sulfur atom.

A method for controlling plant diseases, which method comprises applying to plant pathogens or their habitats, as an effective component, 0.1-10 kg per hectare of a 5-methylthiopyrimidine derivative represented by the following formula (I):

• ##STR49## wherein R.sup.1 means an alkyl group having 1-6 carbon atoms or a phenyl, benzyl, alkenyl or alkoxyalkyl group, R.sup.2 denotes an alkyl group having 1-6 carbon atoms, a phenyl, halogen-substituted phenyl, alkenyl, .omega.-phenyl-substituted alkenyl, alkynyl, alkoxyalkyl, alkoxyalkoxyalkyl, alkylthioalkyl, aminoalkyl, alkoxycarbonylalkyl, aminocarbonylalkyl, furfuryl, thienylmethyl or tetrahydrofuryl group or a ##STR50## in which R.sup.3 and R.sup.4 are individually a hydrogen atom or methyl group, Y means a hydrogen or halogen atom or a methyl or methoxy group, and n stands for an integer of 1 or 2, and X denotes an oxygen or sulfur atom.