12T061A and 12T061C, two new julichrome family compounds, as radical scavengers from Streptomyces sp.

Abstract

We identified two new radical scavengers, 12T061A (1, C₁₉H₂₀O₇) and 12T061C (2, C₂₀H₂₂O₇), from a culture of the Streptomyces sp. Spectroscopic analysis indicated that these compounds are new julichrome family compounds. Compounds 1 and 2 showed radical-scavenging activity with an ED₅₀ of 370 μM and 18 μM, respectively. Moreover, 1 showed tumor cell growth suppressive activity in HepG2 cells, (IC₅₀: 3.6 μM); however, no suppressive activity was shown in 2 (IC₅₀: > 100 μM).