A Modern Comprehensive Treatise. Six-membered heterocyclic compounds with (a) a nitrogen atom common to two or more fused rings (b) one hetero-atom in each of two fused rings. Six-membered ring compounds with two hetero-atoms from Groups VI B, or V B and VI B of the Periodic Table, respectively. Isoquinoline, lupinane and quinolizidine alkaloids. Vol.4 : Heterocyclic compounds. Part H.