Investigation of the regio- and stereoselectivity of the annelation reaction of cyclic Schiff base with structurally asymmetrical β,β′-triketones. Synthesis and properties of 17-acetoxy-8-aza-D-Homogona-12,17a-diones

Article abstract of DOI:10.1007/BF02256981

Annelation ([2+4]-cyclocondensation) of 3,4-dihydroixoquinolines and 2-acetyl-4-acetoxycyclohexane-1,3-dione gives 17-acetoxy-8-aza-D-homogona-12,17a-diones as a mixture of the C(9), C(17)-stereoisomers with the (9R, 17S: 9S, 17R) racemic pair predominating.