Polygonophenone, a naturally MEM-substituted acetophenone from Polygonum maritimum

A new acetophenone, polygonophenone (1) and a new resorcinol, polygonocinol (2), were isolated from the dichloromethane and methanol extracts of Polygonum maritimum (Polygonaceae) and identified as 2-hydroxy-4-[(2-methoxyethoxy)methoxy] acetophenone and 2-methyl-5-nonadecylresorcinol respectively. In addition 12 other known compounds were identified: the sesquiterpenoid (+)-8-hydroxycalamene, four ferulic esters (tetracosyl, hexacosyl, octacosyl and triacontyl ferulate), the arylpropane broussonin B, the hydroquinone glucoside isotachioside, quercetin, quercitrin, (+)-catechin, β-sitosterol, and palmitic acid. The structures of the new compounds were elucidated on the basis of their NMR and MS data. It is noteworthy that the isolation of polygonophenone (1) gives evidence for the use of MEM-protection in biomimetic synthetic strategies. It is the first time that the MEM group is found in the structure of a natural product and its biosynthesis remains unknown.