T. Tanase et al., PHOTOCHEMISTRY OF BUFADIENOLIDE - OCCURRENCE OF 3 TAUTOMERS IN THE PHOTOLYSIS OF RESIBUFOGENIN, Heterocycles, 36(6), 1993, pp. 1411-1416
The photolysis of resibufogenin (1) in MeOH was found to give a fairly
labile mixture of three tautomers (2a-c) by the H-1 nmr spectral anal
ysis including difference NOE experiments.