Microbicidal active substances

A method of antimicrobial treatment of a surface which comprises contacting said surface with an antimicrobially effective amount of a compound of formula

• 19
• wherein
• R1 is C1-C16alkyl, C2-C16alkenyl or C5-C8cycloalkyl, each unsubstituted or substituted by halogen, —CN, —NO2, —C═O, —C═S, —NR2, —OR3, —SR4, —SO2R5, —COOR6 or by a 1,3,4-oxathiazol-2-one radical;
• R2 and R3 are each independently of the other hydrogen;
• C1-C5alkyl;
• C6-C10aryl, or acyl;
• R4 is hydrogen;
• C1-C5alkyl;
• or C6-C10aryl;
• R5 is C1-C5alkyl;
• or C6-C10aryl;
• and
• R6 is hydrogen;
• C1-C5alkyl;
• or C6-C10aryl.

A personal care preparation, comprising

• from 0.01 to 15% by weight, based on the total weight of the composition, of a compound of formula
• 20
• wherein
• R1 is C1-C16alkyl, C2-C16alkenyl or C5-C8cycloalkyl, each unsubstituted or substituted by halogen, —CN, —NO2, —C═O, —C═S, —NR2, —OR3, —SR4, —SO2R5, —COOR6 or by a 1,3,4-oxathiazol-2-one radical;
• R2 and R3 are each independently of the other hydrogen;
• C1-C5alkyl;
• C6-C10aryl, or acyl;
• R4 is hydrogen;
• C1-C5alkyl;
• or C6-C10aryl;
• R5 is C1-C5alkyl;
• or C6-C10aryl;
• and
• R6 is hydrogen;
• C1-C5alkyl;
• or C6-C10aryl,
• and a cosmetically tolerable adjuvant.

An oral composition, comprising

• from 0.01 to 15% by weight, based on the total weight of the composition, of a compound of formula
• 21
• wherein
• R1 is C1-C16alkyl, C2-C16alkenyl or C5-C8cycloalkyl, each unsubstituted or substituted by halogen, —CN, —NO2, —C═O, —C═S, —NR2, —OR3, —SR4, —SO2R5, —COOR6 or by a 1,3,4-oxathiazol-2-one radical;
• R2 and R3 are each independently of the other hydrogen;
• C1-C5alkyl;
• C6-C10aryl, or acyl;
• R4 is hydrogen;
• C1-C5alkyl;
• or C6-C10aryl;
• R5 is C1-C5alkyl;
• or C6-C10aryl;
• and
• R6 is hydrogen;
• C1-C5alkyl;
• or C6-C10aryl,
• and an orally tolerable adjuvant.