Two new polyketides, (5R,7R,9R)-7,9-dihydroxy-5-decanolide and (4E,6R,9R)- 6,9-dihydroxydec-4-enoic acid (2), were isolated from rice cultures of Cylindrocarpon sp. SY-39 discovered during screening of driftwood at a Shonai coast area in Yamagata, Japan. The structures of 1 and 2 were determined using a variety of spectroscopic methods. Compound 2 exhibited moderate antimicrobial activity against Staphylococcus aureus NBRC 13276 and Aspergillus clavatus F 318a at a concentration of 50 μg per disk.

Four novel compounds, cylindropyrone A (1), 10'-hydroxyilicicolinic acid D (3), cylindrolactones A (4) and B (5), together with known dihydroinfectopyrone (2) were isolated from the culture of Cylindrocarpon sp. SY-39 from a driftwood. Their structures were elucidated using 1D- and 2D-NMR spectroscopy. Compound 3 showed antimicrobial activity against Staphylococcus aureus with MIC value of 5.0 μg/mL.