by attack of the N-atom at the carbonyl carbon atom. Under acid conditions, 1-benzylated Reissertcompound 3h cyclised by attack of the resulting N-acyliminium C-atom at the o-position of the benzyl ring to form tetracyclic 1,3-bridged tetrahydroisoquinolines 10 and 11. Bromocyclisation of 1-allyl-2-menthyloxycarbonyl-substituted Reissertcompounds 3b, c led to tricyclic dibromo products 12, in which