| 摘要 |
PURPOSE:To provide a new compound having tyrosinase-inhibitory activity and melanogenesis-suppressive activity, thus useful as a whitening cosmetic, carcinostatic for melanoma, etc., or food blackening inhibitor, etc. CONSTITUTION:The objective compound of formula I (R<1> to R<5> are each OH or lower acyloxy; n is 0 or 1), e.g. 4,6,3',4'-tetrahydroxy-4',5'- dihydrospiro[benzofuran-2(3H),2'(3'H)-dihydrofuran. The compound of the formula I can be obtained by reaction of phloroglucinol of formula II with a pentose (pref. ribose) or hexose (pref. glucose) in the presence of a catalyst such as p-toluenesulfonic acid pref. at 60-90 deg.C to produce a compound of formula III, which is, as necessary, acylated in the presence of a deacidifier such as pyridine. |
