Heterotricyclodecane XXIII 2-Thia-7-aza-isotwistane

2-Thia-7-aza-isotwistanes. The access to the 2-thia-7-aza-isotwistane system was achieved by water addition to the twistene 1 yielding the isotwistanol 2, characterized also as its acetate 4. Analogous D2O/D2SO4-treatment of the twistene 1 ( 3) allowed to deduce the reaction pathway for the formation of 2. The chloride 6, obtained from 2, on treatment with lithium aluminium hydride gave a mixture of unsubstituted isotwistane 8 and twistane 9, whereas silver acetate treatment of 6 led to the isotwistyl acetate 4 and possibly only to traces of the corresponding twistyl acetate 7.