The first aryliodide catalyzed intramolecular C–H amination of phenylurea has been disclosed for high-efficiency synthesis of benzimidazolone derivatives in excellent yields (up to 97%) by an operationally simple one-step organocatalytic oxidative process. Fluorinated protic alcohols can efficiently accelerate the conversion of this transformation. The straightforward method has good functional group
Analogues of N-hydroxy-N′-phenylthiourea and N-hydroxy-N′-phenylurea as inhibitors of tyrosinase and melanin formation
作者:Marc Criton、Véronique Le Mellay-Hamon
DOI:10.1016/j.bmcl.2008.04.079
日期:2008.6
A series of N-hydroxy-N'-phenylthiourea and N-hydroxy-N'-phenylurea analogues were prepared and evaluated as inhibitors of tyrosinase and melanin formation. The most active analogue 1 inhibited mushroom tyrosinase with an IC(50) of around 0.29 mu M and also retained a substantial potency in cell culture by reducing pigment synthesis by 78%. Therefore, compound 1 could be considered as a promising candidate for preclinical drug development for skin hyperpigmentation application. (C) 2008 Elsevier Ltd. All rights reserved.