Bases, and active methylene

An interesting and useful preparation of perhydro-pyrimidines from bis-SchifI bases and active methylene compounds has been published by Takayo et al ° The yields were 30—80%, whereas another approach only afforded 15—60% of these systems (329) and (330). A novel rearrangement of a benzo-pyranopyridine has been reported by Bristol et al and leads to a hydroquin-azolinone. 

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