A New Polysubstituted Benzaldehyde from the co-culture broth of Two Marine Fungi (Strains Nos. E33 and K38)

A new polysubstituted benzaldehyde derivative, ethyl 5-ethoxy-2-formyl-3-hydroxy-4-methylbenzoate (1), was isolated from the co-culture broth of two mangrove fungi (strains Nos. K38 and E33) isolated from the South China Sea coast. The structure of 1 was determined by comprehensive spectroscopic methods, especially 2D NMR techniques. Primary bioassays showed that compound 1 at 0.25 mM inhibited Fusarium graminearum, Gloeosporium musae, Rhizoctonia solani Kuhn, and Phytophthora sojae (Kaufmann & Gerdemann) in 12.06, 11.57, 10.21, and 8.50 mm diameters, respectively.