Stereoselective Synthesis of Spiro Derivatives of 2,4‐Dimethyl‐2,3,4,4a,5,6‐hexahydro‐6H‐benzo[c]quinolizine.

Abstract

Fused pyridine derivatives R 0450Stereoselective Synthesis of Spiro Derivatives of 2,4-Dimethyl-2,3,4,4a,5,6-hexahydro-6H-benzo[c]quinolizine. -The reaction of benzaldehyde derivative (I) with Meldrum's acid and cyclohexane-1,3-dione occurs as tandem of the Knoevenagel condensation and cyclization promoted by the tert-amino effect to afford only one isomer of spiro compounds (III) with axial hydrogen atoms in position 4 and 4a of the benzoquinolizine ring. -(DEEVA, E. V.; GLUKHAREVA, T. V.; ZYBINA, N. A.; MORZHERIN*, Y. Y.; Russ. Chem. Bull. 54 (2005) 6, 1537-1538; Ural State Tech. Univ., Ekaterinburg 620002, Russia; Eng.) -M. Kowall 29-143

Spirocyclic Tetramates by Sequential Knoevenagel and [1,5]-Prototropic Shift

“…This proceeded via isomerisation of the initial kinetic intermediate. While the barbiturate nucleus is well suited to this process, [31][32][33] given our interest in related tetramates both for antibacterial drug discovery 34 and for the generation of novel 3-D drug templates, 35 we examined them for their suitability in the T-reaction. Access to spirocyclic tetramates has been rarely reported.…”