Attempts to prepare some 3-substituted azolo[1,2-x]azines,intermediates in the synthesis of azaaplysinopsin derivatives

Some 3-substituted pyrrolo1,2-a]azines 4a-d were prepared in low yields from the corresponding 2-methylpyridines 1a,b and pyrazine derivatives 1c,d by quaternization with methyl bromoacetate followed by treatment with N,N-dimethylformamide dimethyl acetal. Ethyl 2-pyridinylacetate ( 5 ) and 2-pyridinylaceto-nitrile ( 6 ) were converted with 4-(2-bromo-1-dimethylaminoethylidene)-2-phenyl-5(4H)-oxazolone ( 9 ) into pyrrolo1,2-a]pyridine derivatives 10 and 12 , intermediates in the synthesis of azaaplysinopsins.