NMR Research Today is a free monthly online journal that collates and summarizes the latest research about NMR, including details on nuclear magnetic resonance, structural determination, techniques.

(1)H and (13)C NMR signal assignments of paecilin A and B, two new chromone derivatives from mangrove endophytic fungus Paecilomyces sp. (tree 1-7).

Guo Z, She Z, Shao C, Wen L, Liu F, Zheng Z, Lin Y

School of Chemistry and Chemical Engineering, SunYat-Sen (Zhongshan) University, Guangzhou 510275, PR China.

Two new natural products, named paecilin A (1) and B (2), together with two known compounds secalonic acid D (3) and (11)-cytochalasa-6(12),13-diene-1,21-dione-16,18-dimethyl-7-hydroxy-10-phenyl-(7S*,13E,16S*,18S*) (4), were isolated from the mangrove endophytic fungus, Paecilomyces sp. (tree 1-7) from the South China Sea. 1D and 2D NMR experiments including COSY, HMQC, and HMBC were used for the determination of their structures. In our cytotoxicity assays, secalonic D (3) showed cytotoxicity toward KB cells with IC(50) < 1 microg ml(-1) and inhibiting human topoisomerase I with IC(50) at 0.16 micromol ml(-1). 1, 2, and 4 showed no activity to KB cells.

Published 6 August 2007 in Magn Reson Chem, 45(9): 777-80.
Full-text of this article is available online (may require subscription).

© 2005-2008 NMR Research Today. All Rights Reserved.