Isolation of a new butenolide from the South China Sea gorgonian coral <i>Subergorgia suberosa</i> ZhangJun LiangYan LiaoXiao-Jian DengZhou XuShi-Hai 2014 <div><p>Chemical investigation on the South China Sea gorgonian coral <i>Subergorgia suberosa</i> has led to the isolation of one new butenolide (5<i>R</i>)-5-(1-ethoxypropyl)-5-hydroxy-3,4-dimethylfuran-2(5<i>H</i>)-one (<b>1</b>) as a pair of inseparable epimers, along with two known butenolides (<i>S</i>)-5-hydroxy-3,4-dimethyl-5-propylfuran-2(5<i>H</i>)-one (<b>2</b>) and (<i>S</i>)-5-hydroxy-3,4-dimethyl-5-pentylfuran-2(5<i>H</i>)-one (<b>3</b>). Their structures including absolute configurations were determined unambiguously by detailed analyses of spectroscopic data and by comparison with the available literature. Compounds <b>1</b>–<b>3</b> exhibited moderate antifouling activities against the settlement of <i>Balanus amphitrite</i> larvae, whereas compound <b>4</b>, the acetyl derivative of <b>3</b>, showed no antifouling activity at the concentrations up to 25 μg/mL.</p></div>