Synthesis of hexahydropyrazino[1,2-b]isoquinolines as simplified saframycin analogues

Abstract

Various hexahydropyrazino[1,2-b]isoquinolines were synthesised as simplified saframycin analogues. Construction of this core proceeded through a tetrahydroisoquinoline synthesis followed by acylation/alkylation of the tetrahydroisoquinoline nitrogen and subsequent ring closure using various aliphatic and aromatic amines. The resulting piperazinones were reacted with LiAlH4 or LiAlH(OEt)3 to synthesise further analogues. © Georg Thieme Verlag Stuttgart · New York.