Divergent Synthesis of Bioactive Resorcinols Isolated from the Fruiting Bodies of Hericium erinaceum: Total Syntheses of Hericenones A, B, and I, Hericenols B–D, and Erinacerins A and B

• Published in: Journal of organic chemistry Vol. 79; no. 11; pp. 5227 - 5238
• Main Authors: Kobayashi, Shoji, Tamanoi, Hidetsugu, Hasegawa, Yuichi, Segawa, Yusuke, Masuyama, Araki
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 06.06.2014; Amer Chemical Soc
• Subjects: Biological Products - chemical synthesis; Biological Products - chemistry; Chemistry; Chemistry, Organic; Heterocyclic Compounds, 2-Ring - chemical synthesis; Heterocyclic Compounds, 2-Ring - chemistry; Heterocyclic Compounds, 3-Ring - chemical synthesis; Heterocyclic Compounds, 3-Ring - chemistry; Indoles - chemical synthesis; Indoles - chemistry; Lactams - chemistry; Molecular Structure; Phenols - chemical synthesis; Phenols - chemistry; Physical Sciences; Resorcinols - chemical synthesis; Resorcinols - chemistry; Resorcinols - isolation & purification; Science & Technology; Terpenes - chemical synthesis; Terpenes - chemistry; SECONDARY ALCOHOLS; HERICERIN; MILD; SELECTIVE OXIDATION; REAGENTS; CATALYST; AROMATIC-COMPOUNDS
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo500795z

Total syntheses of 5′- and 7′-oxidized geranyl resorcylates isolated from the fruiting bodies of Hericium erinaceum and the submerged cultures of a Stereum species were achieved. Our synthesis features derivatization of a suitably functionalized 5′-oxidized geranyl phthalide as a common intermediate, which was obtained by Stille coupling between the phthalide core and the side chain, into a series of natural products by divergent functional group manipulations. The crucial C5′-oxygen functionality was installed at the initial stage by alkylation by an α-cyano ethoxyethyl ether. From a common synthetic intermediate, eight total syntheses including hericenones A, B, and I, hericenols B–D, and erinacerins A and B were achieved (hericenol B and erinacerin B were synthesized as racemates). The structure of hericenone B established in the isolation paper was unambiguously revised as the carbonyl regioisomer at the lactam moiety.