Structures and Aldose Reductase Inhibitory Effects of Bromophenols from the Red Alga Symphyocladia latiuscula

Abstract

Three new bromophenols, 2,2',3,6,6'-pentabromo-3',4,4',5-tetrahydroxydibenzyl ether (1), bis(2,3,6-tribromo-4,5-dihydroxyphenyl)methane (2), and 2,2',3,5',6-pentabromo-3',4,4',5-tetrahydroxydiphenylmethane (3), were isolated from the red alga Symphyocladia latiuscula. Two bromophenols, 2,3,6-tribromo-4,5-dihydroxymethylbenzene (4) and 2,3,6-tribromo-4,5-dihydroxybenzaldehyde (5), were also reported for the first time as natural products. Their structures were elucidated on the basis of chemical and spectroscopic methods including HREIMS, HRFABMS, and 1D and 2D NMR spectral techniques. Compounds 1-5 exhibited significant aldose reductase inhibitory activity.

Synthesis and paroxonase activities of novel bromophenols

“…It has been reported that naturally occurring bromophenol 1 shows enzyme inhibition 3 , cytotoxicity 4 , feeding deterrent 5 , anti-microbial 6 , anti-cancer 7 and anti-oxidant 8 activities. Aldose reductase 9 and carbonic anhydrase 10 inhibitory properties of natural products 2-3 have also been noted ( Figure 1). The high-density lipoprotein associated serum esterase, paraoxonase (arylesterase, EC 3.1.8.1, PON1) is a key enzyme for protection against atherosclerosis in metabolism.…”

Halogenated Organic Molecules of Rhodomelaceae Origin: Chemistry and Biology

“…389 Bromophenols 633−634, 659−660, and 676 exhibited significant aldose reductase inhibitory activity with IC 50 values ranging from 0.11 to 1.15 μg/mL, and the effect was similar to (633) or higher than (634, 659−660, and 676) that of the positive control (quercetin). 373 The bromophenols vidalols A (664) and B (685) are antiinflammatory agents that act through inhibition of phospholipase A 2 , causing 96% inactivation at 1.6 μg/mL. 386 However, it was difficult to maintain the purity of vidalols A and B during the bioassay, so it was not clear whether the inhibitory activity was caused by the compounds themselves or by degradation products thereof.…”

Synthesis and carbonic anhydrase inhibitory properties of novel bromophenols including natural products

“…Of these natural compounds, 5,5′-methylenebis(3,4-dibromobenzene-1,2-diol) (1) and 3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(methoxymethyl)benzyl)benzene-1,2-diol (2) exhibit enzyme inhibition, e.g. isocitrate lyase 3 cytotoxicity 4 , feeding deterrent 5 , and microbial 6,7 activities, while 3,4,6-tribromo-5-(2,5-dibromo-3,4-dihydroxybenzyl) benzene-1,2-diol (3) and 5,5′-methylenebis(3,4,6-tribromo-benzene-1,2-diol) (4) exhibit significant aldose reductase inhibitory activity 8 . Additionally, it was reported that bromophenol 1 is an inhibitor of protein tyrosine phosphatase 9 .…”