A concise route to a small family of exotic marine alkaloids known as the araiosamines has been developed;
and their absolute configuration has been assigned. The dense array of functionality;
high polarity;
and rich stereochemistry coupled with equilibrating topologies present an unusual challenge for chemical synthesis and an opportunity for innovation. Key steps involve the use of a new reagent for guanidine installation;
a remarkably selective C-H functionalization;
and a surprisingly simple final step that intersects a presumed biosynthetic intermediate. Synthetic araiosamines were shown to exhibit potency against Gram-positive and -negative bacteria despite a contrary report of no activity. © 2016 American Chemical Society;