8.91 (C-17 and C-19 methyls), and T 5.15 and 5.43 (C-20 exocyclic methylene). An AB quartet was present at T 5.38, 5.56, 5.81, and 5.99 for a C-18 CHIO RS in 18-hydroxy-13- epimanool (2), but further downfield owing to formation of the ester group. A multiplet for a single C-14 vinylic proton was present at T 4.6 as in contortolal semicarbnzone. Analogously, the C-16 vinylic methyl appeared at 7 8.21, and a doublet appeared at T ...
