Journal
JOURNAL OF NATURAL PRODUCTS
Volume 81, Issue 4, Pages 749-757Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.jnatprod.7b00454
Keywords
-
Funding
- National Natural Science Foundation of China [31570350, 31602112]
- Scientific Research Foundation of Shenyang Agricultural University [880415026]
Ask authors/readers for more resources
With bioassay- and chemistry-guided fractionation, seven new caged prenylxanthones including two scalemic mixtures, epiisobractatin (1), 13-hydroxyisobractatin (2), 13-hydroxyepiisobractatin (3), 8-methoxy-8,8a-dihydrobractatin (4), 8-ethoxy-8,8a-dihydrobractatin (5), garcibracteatone (6), and 8-methoxy-8,8a-dihydroneobractiatin (7), and the eight known compounds 8-15 were isolated from the leaves of Garcinia bracteata. The structures were unambiguously elucidated through analysis of spectroscopic data. The 2D structures and relative configurations of 1 and 5 were confirmed by X-ray crystallographic analysis. The separation of the enantiomers of 1-5 was accomplished by chiral-phase HPLC. The absolute configurations of the enantiomers of 1 and 5 were assigned by comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. The absolute configurations of the related compounds were determined via comparisons of their ECD data with those of the enantiomers of 1 and 5, respectively. Notably, compound 7, with a neo caged skeleton, is the first representative of a novel type of caged xanthone lacking a Delta(8(8a)) double bond. The isolated compounds exhibited significant cell growth inhibitory activities in vitro against human leukemic HL-60. and K562 cell lines, with GI(50) values ranging from 0.2 to 8.8 mu M. A preliminary structure- activity relationship is discussed.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available