Isolation and structure of a 20,21-epoxybufenolide series from "Ch'an Su".
Steroid bufenolides resulting from epoxidation of the 17beta-2-pyrone ring of bufadienolides are rare. Five 20,21-epoxybufenolides, namely, 20S,21-epoxyresibufogenin (1), 20R,21-epoxyresibufogenin (2), 3-O-formyl-20S,21-epoxyresibufogenin (3), 3-O-formyl-20R,21-epoxyresibufogenin (4), and 3-oxo-20S,21-epoxyresibufogenin (5), were isolated from the Chinese toad skin extract drug Ch'an Su. The structures were elucidated by spectroscopic and chemical methods. The configuration at C-20 was assigned by the analysis of difference NOE spectra. The cancer cell (KB and MH-60) growth inhibition by the new 20,21-epoxybufenolides was examined, and 20,21-epoxides 1, 2, and 5 were found to significantly inhibit the leukemia MH-60 cell line.
Kamano
Yoshiaki
Y
Faculty of Science, Kanagawa University, 2946 Tsuchiya, Hiratsuka, Kanagawa 259-1293, Japan.
Nogawa
Toshihiko
T
Yamashita
Ayano
A
Hayashi
Masahiko
M
Inoue
Masuo
M
Drasar
Pavel
P
Pettit
George R
GR
D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002018:Bufanolides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002025:Bufonidae; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004354:Drug Screening Assays, Antitumor; D004852:Epoxy Compounds / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D018922:HL-60 Cells / Q000187:drug effects; D006801:Humans; D007624:KB Cells / Q000187:drug effects; D007951:Leukemia, Myeloid; D009682:Magnetic Resonance Spectroscopy; D008516:Medicine, Chinese Traditional; D051379:Mice; D008968:Molecular Conformation; D015394:Molecular Structure; D009303:Nasopharyngeal Neoplasms; D012867:Skin / Q000378:metabolism; D013055:Spectrophotometry, Infrared; D013237:Stereoisomerism; D014407:Tumor Cells, Cultured / Q000187:drug effects
D000970:Antineoplastic Agents; D002018:Bufanolides; D004852:Epoxy Compounds; C095591:chan su