Synthesis and structure of novel 4‐arylhexahydro‐1<i>H</i>,3<i>H</i>‐pyrido[1,2‐<i>c</i>]pyrimidine derivatives

Abstract

Abstract A series of new 4‐aryl‐hexahydro‐1 H ,3 H ‐pyrido[1,2‐ c ]pyrirnidine‐1,3‐dione derivatives 4a‐k were prepared by catalytic hydrogenation of 4‐aryl‐1 H ,2 H ‐pyrido[1,2‐ c ]pyrirnidine‐1,3‐diones 3a‐k. The structures of compounds were determined by 1 H and 13 C nmr spectroscopy in solution. Steric hindrance caused twisting of the phenyl ring with respect to the pyridopyrimidine system, the effect was confirmed by X‐ray diffraction.