Abstract
Three new abietane diterpenes, sugikurojins D (1), E (2), and F (3), and two new abietanes which incorporate cadinane, sugikurojins G (4) and H (5) were isolated from the bark of Cryptomeria japonica. These structures were elucidated primarily by extensive NMR experiments. The structure of sugikurojin D (1) was deduced to be 6α-acetoxy-7β,11-dihydroxy-12-methoxy-8,11,13-abietatriene. Sugikurojin E (2) was deduced to be 6α-acetoxy-7β,12-dihydroxy-8,11,13-abietatriene. Sugikurojin F (3) was 7α-methoxy-8,13-abietadien-11,12-dione. Sugikurojins G (4) and H (5) had a unique skeleton incorporating an α-cadinol or a 1α-hydroxy-T-cadinol in ferruginol, respectively. Also obtained in this investigation were the known diterpenes (6—14). An antibacterial activity of ten among these against Staphylococcus aureus and Escherichia coli was inactive at the (MIC: 125 μg/ml) level. Meanwhile, in the cytotoxic activity against HL-60, compounds 4, 8, and 11 showed moderate (IC50: 4, 35.4; 8, 28.0; 11, 52.4 μM) though weak (IC50: 4, 100; 8, 80.8; 11, 100 μM) activity against HCT-15.
