| 摘要 |
3,4-Dihydroxybenzyl-substituted carbonic acid derivatives (I) are new. Carbonic acid derivatives of formula (I) (including their tautomers) are new. [Image] X1-X3O, S or NR3; R1H, R4, OH or OR4; R4alkyl, alkenyl, 1-oxoalkyl or 1-oxoalkenyl (all having up to 5C); R2H, linear, branched or cyclic alkyl or alkenyl of 1-22C (in which at least one C is optionally replaced by O), or ring-substituted (but halogen-free) 7-15C aralkyl, and R3H, or linear, branched or cyclic alkyl or alkenyl of 1-22C (in which at least one C is optionally replaced by O). An independent claim is included for the preparation of (I). - ACTIVITY : Dermatological; Antioxidant. - MECHANISM OF ACTION : Radical scavenger. In radical scavenging tests using DPPH (1,1-diphenyl-2-picryl hydrazyl) as test radical, N-(3,4-dihydroxybenzyl)-N'-(n-hexyl)-thio urea (Ia) had an EC50 value of 0.06 mol/mol, compared with 0.27 mol/mol for vitamin C. |
