p. 1221,1222, 1223, 1225
(1966)p. 1535 - 1540
(2007/10/02)p. 3536 - 3543
(2007/10/02)acetic anhydride
(3S,3aS,4S,4aS,6S,8aR,8bR,11S)-6,11-dihydroxy-3-methyl-12-methylene-2-oxo-4a,6-ethano-3,8b-prop-1-enoperhydroindeno[1,2-b]furan-4-carboxylic acid