At least 92%; secondary component 3-6% dipropyl disulfide

At least 92 %; secondary component 3-6 % dipropyl disulfide

The invention concerns the use of 8-(3-oxocyclopentyl)-1,3-dipropyl-7H-purine-2,6-dione.

At least 90%; secondary components 4-5% methyl 1-dipropyl disulfide and 2-4% propenyl disulfide

At least 90 %; secondary components 4-5 % methyl 1-dipropyl disulfide and 2-4 % propenyl disulfide

In the synthetic scheme disclosed herein benzillic acid 1 is directly converted to di-propyl ester ether 7 from the known standard method.

The composition preferably comprises titanium dioxide as the inorganic compound and N, N-diethyl-m-toluamide and dipropyl pyridine-2,5-dicarboxylate as insect repellents.