Chemistry makes scents

Welcome to this month's crossword, constructed by Irene Cesa, a retired chemist from Wheaton, Illinois, and George Barany, professor emeritus of chemistry at the University of Minnesota Twin Cities. They thank Jeff Aubé, Mark Cesa, Jed Fisher, and Michael Hanko for test solving and editorial suggestions. C&EN thinks that puzzle solvers will enjoy getting this whiff of natural product chemistry.