Bicyclic 5-6 and 5-7 Ring Systems

A derivative of the related pyrrolo[l,2-a]pyrimidine system 84 was prepared from L-asparagine via a hydroxypyrrolidine (92JOC2641). 

In the synthesis of the alkaloid gephyrotoxin, L-pyroglutamic acid was used as a starting material for the preparation of intermediate 85 (81TL4197). A related pyrrolooxazine 86 was also obtained from pyroglu-tamic acid after A-substitution and ring closure in the presence of silica 

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