This lecture delves into the concept of pattern recognition in total synthesis, emphasizing the discovery of substructural motifs to guide the synthesis process. Key motifs like 3-Acyl proline are explored through examples such as Oppolzer's synthesis of Longifolene and Qin's synthesis of Minfiensine. The lecture also covers the synthesis of Actinophyllic acid, highlighting important steps like the Aza-Cope/Mannich sequence and conformation analysis. Various synthesis pathways are discussed, showcasing the intricate strategies employed in total synthesis.