Synthesis and structure–activity relationship of 3-O-acylated (–)-epigallocatechins as 5α-reductase inhibitors
摘要:
A series of 3-O-acylated (-)-epigallocatechins were synthesized and their inhibition of steroid 5 alpha-reductase was studied. They were prepared from the reaction of EGCG with tert-butyldimethylsilyl chloride followed by reductive cleavage of the ester bond. The resultant (-)-epigallocatechins penta-O-tert-butyldimethylsilyl ether was esterified with different fatty acids then desilylated to provide the corresponding products. The activity of 3-O-acylated (-)-epigallocatechins increased with the increasing carbon numbers of the fatty acid moiety, reaching maximum for 16 carbon atoms (compound 4h) with an IC50 of 0.53 mu M, which was similar to 12-fold more potent than EGCG (IC50 = 6.29 mu M). Introduction of monounsaturated fatty acid provided the most potent compound 6 (IC50 = 0.48 mu M), which showed moderate anti-tumor activity in vivo. (C) 2010 Elsevier Masson SAS. All rights reserved.