Synthesis of (±)‐Desmarestene and (±)‐Viridiene, the Two Sperm Releasing and Attracting Pheromones from the Brown Algae <i>Desmarestia aculeata</i> and <i>Desmarestia viridis</i>

Abstract

Abstract Desmarestene 1 6‐(1 Z ,3‐butadienyl)‐1,4‐cycloheptadiene and viridiene 3 cis ‐3‐(1 Z , 3‐butadienyl)‐4‐vinylcyclopentene are chemical messengers for male gametes of the brown algae Desmarestia aculeate and Desmarestia viridis . Total syntheses of 1 , 3 and their stereoisomers 1a , 3a ‐ c are reported. Gas‐chromatographic comparison of synthetic 1 and 3 with the corresponding natural products has established their structural identity.