TY - JOUR
T1 - Khayanolides from African mahogany Khaya senegalensis (Meliaceae)
T2 - A revision
AU - Zhang, Huaping
AU - Tan, Junjie
AU - VanDerveer, Don
AU - Wang, Xi
AU - Wargovich, Michael J.
AU - Chen, Feng
N1 - Funding Information:
The authors wish to thank Ms. Barbara Ramirez, Director of the Writing Center at Clemson University, for her help in the preparation of this manuscript. In addition, they are grateful to the financial support from a grant, R21CA107138, from National Institutes of Health (NIH), Bethesda, MD, USA, and the Clemson University Vice President’s Research Investment Fund.
PY - 2009/1
Y1 - 2009/1
N2 - Five khayanolides (1-O-acetylkhayanolide B 1, khayanolide B 2, khayanolide E 3, 1-O-deacetylkhayanolide E 4, 6-dehydroxylkhayanolide E 5) were isolated from the stem bark of African mahogany Khaya senegalensis (Meliaceae). Their structures and absolute configurations were determined through extensive spectroscopic analyses including MS, NMR, and single-crystal X-ray diffraction experiments. The results established that two previously reported khayanolides, 1α-acetoxy-2β,3α,6,8α,14β-pentahydroxy-[4.2. 110,30.11,4]-tricyclomeliac-7-oate 6 and 1α,2β,3α,6,8α,14β-hexahydroxy-[4.2.110, 30.11,4]-tricyclomeliac-7-oate 7, were, in fact, 1-O-acetylkhayanolide B 1 and khayanolide B 2, and that the two reported phragmalin derivatives, methyl 1α-acetoxy-6,8α,14β,30β-tetrahydroxy-3-oxo- [3.3.110,2.11,4]-tricyclomeliac-7-oate 8 and methyl 1α,6,8α,14β,30β-pentahydroxy-3-oxo-[3.3.110,2 .11,4]-tricyclomeliac-7-oate 9, were, in fact, khayanolide E 3 and 1-O-deacetylkhayanolide E 4, respectively. Based on the results from this study and consideration of the biogenetic pathway, the methyl 6-hydroxyangolensate in African mahogany K. senegalensis should have a C-6 S configuration while methyl 6-hydroxyangolensate in genuine mahogany Swietenia species should have a C-6 R configuration.
AB - Five khayanolides (1-O-acetylkhayanolide B 1, khayanolide B 2, khayanolide E 3, 1-O-deacetylkhayanolide E 4, 6-dehydroxylkhayanolide E 5) were isolated from the stem bark of African mahogany Khaya senegalensis (Meliaceae). Their structures and absolute configurations were determined through extensive spectroscopic analyses including MS, NMR, and single-crystal X-ray diffraction experiments. The results established that two previously reported khayanolides, 1α-acetoxy-2β,3α,6,8α,14β-pentahydroxy-[4.2. 110,30.11,4]-tricyclomeliac-7-oate 6 and 1α,2β,3α,6,8α,14β-hexahydroxy-[4.2.110, 30.11,4]-tricyclomeliac-7-oate 7, were, in fact, 1-O-acetylkhayanolide B 1 and khayanolide B 2, and that the two reported phragmalin derivatives, methyl 1α-acetoxy-6,8α,14β,30β-tetrahydroxy-3-oxo- [3.3.110,2.11,4]-tricyclomeliac-7-oate 8 and methyl 1α,6,8α,14β,30β-pentahydroxy-3-oxo-[3.3.110,2 .11,4]-tricyclomeliac-7-oate 9, were, in fact, khayanolide E 3 and 1-O-deacetylkhayanolide E 4, respectively. Based on the results from this study and consideration of the biogenetic pathway, the methyl 6-hydroxyangolensate in African mahogany K. senegalensis should have a C-6 S configuration while methyl 6-hydroxyangolensate in genuine mahogany Swietenia species should have a C-6 R configuration.
KW - 1-O-acetylkhayanolide B
KW - 1-O-deacetylkhayanolide E
KW - 6-Dehydroxylkhayanolide E
KW - African mahogany
KW - Khaya senegalensis
KW - Khayanolide
KW - Khayanolide B
KW - Khayanolide E
KW - Limonoid
KW - Meliaceae
KW - Methyl 6-hydroxyangolensate
KW - Structure revision
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U2 - 10.1016/j.phytochem.2008.12.004
DO - 10.1016/j.phytochem.2008.12.004
M3 - Article
C2 - 19136128
AN - SCOPUS:60449094720
VL - 70
SP - 294
EP - 299
JO - Phytochemistry
JF - Phytochemistry
SN - 0031-9422
IS - 2
ER -