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Updated: Aug 11, 2026

Quantification of Hypopigmentation Activity In Vitro
Published on: March 6, 2019
Synthesis of tyrosinase inhibitory kojic acid derivative
Yong Sup Lee1, Jang Hyun Park, Min Hwan Kim
1Division of Life Sciences, Korea Institute of Science and Technology, Seoul, Korea. kyslee@khu.ac.kr
Abstract:
Kojic acid derivative 2 was synthesized by joining two pyrone rings through an ethylene linkage by Horner-Emmons reaction of phosphonate 6 with aldehyde 7. The intermediates 6 and 7 were derived from kojic acid. The tyrosinase inhibitory activity of 2 was about 8 times more potent (IC(50) = 3.63 microM) than that of kojic acid (IC(50) = 30.61 microM). Compound 2 also exhibited potent melanin synthesis inhibitory activity (19.53% inhibition at 5 mug) indicating that the connection of two pyrone rings of kojic acid through a suitable linker can be an useful strategy for identification of potent tyrosinase inhibitors.
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