Synthesis and protein tyrosine phosphatase 1B inhibition activities of two new synthetic bromophenols and their methoxy derivatives

摘要

3-bromo-4,5-bis(2,3-dibromo-4,5-dihydroxybenzyl)-l,2-benzenediol (1) is a natural bromophenol isolated from the red algae Rhodomela confervoides that exhibits significant inhibition against protein tyrosine phosphatase 1B (PTP 1B).Based on its activity,we synthesized two new synthetic bromophenols and their methoxy derivatives from vanillin using the structure of natural bromophenol 1 as a scaffold.The structures of these bromophenols were elucidated from 1H NMR,13C NMR,and high resolution electron ionization mass spectrometry as 2,3-dibromo-1-(2'-bromo-6'-(3",4"-dimethoxybenzyl)-3',4'-dimethoxybenzyl)-4,5-dimethoxybenzene (2),2,3-dibromo- 1-(2'-bromo-6'-(2"-bromo-4",5"-dimethoxy-benzyl)-3',4'-dimethoxybenzyl)-4,5-dimethoxybenzene (3),3,4-dibromo-5-(2'-bromo-6'-(2"-bromo-4",5"-dihydroxybenzyl)-3',4'-dihydroxybenzyl)pyrocatechol (4) and 3,4-dibromo-5-(2'-bromo-6'-(3",4"-dihydroxybenzyl)-3',4'-dihydroxybenzyl)pyrocatechol (5).PTPI B inhibition activities of these compounds were evaluated using a colorimetric assay,and compounds 3 and 4 demonstrated interesting activity against PTP1B.