Highly efficient construction of pentacyclic benzo[b]indeno-[1,2,3-de][1,8]naphthyridine derivatives via four-component domino reaction.

A series of new octahydrobenzo[b]indeno[1,2,3-de][1,8] naphthyridine and decahydropyrido[2,3,4-gh]phenanthridine derivatives were synthesized via a four-component domino reaction under microwave irradiation. This one-pot transformation, which involved multiple steps and did not require the use of a catalyst, constructed four new C-C bonds, two new C-N bonds, and three new rings, with efficient use of all reactants.