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Two new aloceramides from alocasia macrorrhiza

Two new aloceramides alomacrorrhiza A and alomacrorrhiza B were isolated from the ethanolic extract of the plant Alocasia macrorrhiza (L.) Schott. Their chemical structures were elucidated as (2S,3S,4R)-2N-[(2'R)-2'-hydroxy-hexacosanoyl]-tetradecane-1,3,4-triol (1) and (2S,3S,4R)-2N-[(2'R)-2'-hydroxy-hexacosanoyl]-hexadecane-1,3,4-triol (2) based on extensive 1D, 2D NMR, EI-MS, FAB-MS, HR-FAB-MS spectroscopic data and chemical degradation studies. | Journal of Chemistry Vol. 43 4 P. 513 - 516 2005 TWO NEW ALOCERAMIDES FROM ALOCASIA MACRORRHIZA Received 26th July 2004 NGUYEN QUYET TIEN1 II PHAM HOANG NGOC1 PHAM HONG MINH1 PHAN VAN KIEM2 AND YOUNG HO KIM3 institute of Chemistry Vietnamese Academy of Science and Technology institute of Natural Products Chemistry Vietnamese Academy of Science and Technology 3College of Pharmacy Chungnam National University Daejeon 305-764 Korea SUMMARY Two new aloceramides alomacrorrhiza A and alomacrorrhiza B were isolated from the ethanolic extract of the plant Alocasia macrorrhiza L. Schott. Their chemical structures were elucidated as 2S 3S 4R -2N- 2 R -2 -hydroxy-hexacosanoyl -tetradecane-1 3 4-triol 1 and 2S 3S 4R -2N- 2 R -2 -hydroxy-hexacosanoyl -hexadecane-1 3 4-triol 2 based on extensive 1D 2D NMR EI-MS FAB-MS HR-FAB-MS spectroscopic data and chemical degradation studies. Keywords Araceae Alocasia macrorrhiza ceramide alomacrorrhiza A alomacrorrhiza B. I - INTRODUCTION Alocasia macrorrhiza L. Schott Araceae is widely distributed in Vietnam and used as a folk medicine to treat inflammation eczema and abscess 2 5 . Alocasin an anti-fungal protein and trypsin inhibitor has been isolated from the giant taro A. macrorrhiza 1 3 7 . We report herein the isolation and structural elucidation of two new ceramides 2S 3S 4R -2N- 2 R -2 -hydroxy-hexacosanoyl -tetradecane- 1 3 4-triol 1 and 2S 3S 4R -2N- 2 R -2 -hydroxy-hexa-co-sanoyl -hexadecane-1 3 4-triol 2 from the ethanolic extract of A. macrorrhiza. II - MATERIALS AND METHODS General experimental procedures Melting points were determined using an Electrothermal IA-9200. IR spectrum was obtained on a Hitachi 270-30 type spectrometer with KBr discs. Optical rotations were determined on a JASCO DIP-1000 KUY polarimeter. EI-MS was obtained using a Hewlett Packard 5989 B MS spectrometer. FAB-MS and HR-FAB-MS were obtained using a JEOL JMS-DX 300 spectrometer. 1H-NMR 500 MHz and 13C-nMr 125 MHz were recorded on a Bruker AM500 FT-NMR .