TY - JOUR
T1 - Bufadienolides. 32. Selenium Dioxide Dehydrogenation of 14-Dehydrobufalin
AU - Pettit, George
AU - Kamano, Yoshiaki
AU - Inoue, Masuo
AU - Komeichi, Yoshihisa
AU - Nassimbeni, Luigi R.
AU - Niven, Margaret L.
PY - 1982/1/1
Y1 - 1982/1/1
N2 - Unlike digitoxigenin acetate (1), bufalin acetate (5a), resibufogenin acetate (6a), and cinobufagin acetate (6b) were found to be resistant to selenium dioxide hydroxylation (e.g., 1 → 2). However, under similar conditions selenium dioxide was found to dehydrogenate 14-dehydrobufalin (7a) to 3β-hydroxy-5β-bufa-8,14,20,22-tetraenolide (8a). An analogous dehydrogenation reaction was observed by employing 14-dehydrobufalin acetate (7b → 8b). The structure of tetraene 8 was confirmed by dehydration of alcohol 10 to yield the same tetraene (8b). In turn, the structure of alcohol 10 prepared from α-epoxide 9 was substantiated by an X-ray crystallographic study of o-nitrobenzoate derivative 11.
AB - Unlike digitoxigenin acetate (1), bufalin acetate (5a), resibufogenin acetate (6a), and cinobufagin acetate (6b) were found to be resistant to selenium dioxide hydroxylation (e.g., 1 → 2). However, under similar conditions selenium dioxide was found to dehydrogenate 14-dehydrobufalin (7a) to 3β-hydroxy-5β-bufa-8,14,20,22-tetraenolide (8a). An analogous dehydrogenation reaction was observed by employing 14-dehydrobufalin acetate (7b → 8b). The structure of tetraene 8 was confirmed by dehydration of alcohol 10 to yield the same tetraene (8b). In turn, the structure of alcohol 10 prepared from α-epoxide 9 was substantiated by an X-ray crystallographic study of o-nitrobenzoate derivative 11.
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U2 - 10.1021/jo00347a026
DO - 10.1021/jo00347a026
M3 - Article
AN - SCOPUS:0345662162
SN - 0022-3263
VL - 47
SP - 1503
EP - 1506
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
IS - 8
ER -