The present description discloses a novel biologically active ingredient of manuka honey. Specially, the present description discloses a compound represented by the following formula. In this formula, each of R1, R2 and R3 independently represents a hydrogen atom or optionally substituted C1-4 alkyl group, m represents an integer from 1 to 3, each of R4-m, R5-m and R6-m independently represents a hydrogen atom or optionally substituted C1-4 alkyl group, and each of R7, R8, R9 and R10 independently represents a hydrogen atom or optionally substituted C1-4 alkyl group.
