We have developed a simple method for cross‐aldol condensation reaction to provide (1E,4E)‐1‐(2‐(allyloxy)aryl)‐5‐(2‐(allyloxy)aryl)penta‐1,4‐dien‐3‐ones (7 a–j) and (E)‐1‐(2‐(allyloxy)aryl)‐5‐(2‐(allyloxy)aryl)pent‐1‐en‐3‐ones (8 a–e) in 67–88 % and 73–86 % yields, respectively. Subsequently a series of dibenzo‐fused 15‐membered dioxa‐ketone macrocycles 9 a–j (61‐95 %) and 10 a–e (70‐90 %) have been synthesized from 7 a–j and 8 a–e, respectively, through ring‐closing metathesis reaction employing Grubbs’ third generation catalyst. The cis/trans‐configurations of products (9 a–j) and (10 a–e) were established from their 1H‐NMR spectral data.

This review reports the synthesis of various bioactive macrocycles, involving ring-closing metathesis as a key step, developed since ca. 2000. These macrocycles exhibited biological activities such as antiviral, antifungal, antibacterial, and anticancer activities, and more. Thus, their syntheses and utilization are essential for both synthetic organic and medicinal chemists.