Studies on Antineoplastic Constituents from Marine Bryozoan Bugula neritina Inhabiting South China Sea: Isolation and Structural Elucidation of a Novel Macrolide Bryostatin 19

摘要

Objective: To investigate the antineoplastic constituents from marine bryozoan Bugula neritina inhabiting South China Sea. Methods: Antineoplastic compounds were screened by bioassay-guided method with a combination of extraction and partitionation as well as multiple column chromatographies (Sephadex LH-20, ODS and preparative HPLC). Structures of active compounds were established by employing high-resolution 2D NMR (600 MHz) and ESI-MS techniques. Results: A new antineoplastic macrolide bryostatin 19 (1) was isolated from this animal. Five known bryostatins: bryostatin 4 (2), bryostatin 5 (3), bryostatin 6 (4), bryostatin 18 (5) and bryostatin 10 (6), were for the first time obtained from this bryozoan in South China Sea. Conclusion: Bryostatin 19 (1) showed significant inhibition activity against U937 cell line with ED50 value of 3.2 nmol/L in vitro.