Ambrafuran (AmbroxTM) Synthesis from Natural Plant Product Precursors

Abstract

Ambergris, an excretion product of sperm whales, has been a valued agent in the formulation of perfumes. The composition of ambergris consists of two major components: 40–46% cholestanol type steroids and approximately 25–45% of a triterpenoid known as ambrein. Ambergris undergoes oxidative decomposition in the environment to result in odorous compounds, such as ambraoxide, methylambraoxide, and ambracetal. Its oxidized form, ambrafuran (IUPAC name: 3a,6,6,9a-tetramethyl-2,4,5,5a,7,8,9,9b-octahydro-1H-benzo[e][1]benzofuran), is a terpene furan with a pleasant odor and unique olfactive and fixative properties. The current state of the fragrance industry uses ambrafuran materials entirely from synthetic or semisynthetic sources. However, natural compounds with the potential to be converted to ambergris-like odorants have been extracted from several different types of plants. Here we review plant terpenoids suitable as starting materials for the semisyntheses of ambrafuran or intermediates, such as ambradiol, that can be used in biocatalytic transformations to yield ambrafuran.

From Ambergris to (−)-Ambrox: Chemistry Meets Biocatalysis for Sustainable (−)-Ambrox Production

“…Other natural mono- and polycyclic terpenes have been used as biosourced starting materials for the synthesis of (−)-ambrox (Scheme ), e.g., dysongensin A, oleanolic acid, labdanolic acid, − S -(+)-carvone, thujone, communic acid, (+)- Z -abienol, levopimaric acid, (−)-drimenol, l -abietic acid, and manoyl oxide, as well as labdane type diterpenoids. , A very recent review summarizes the above syntheses of (−)-ambrox from natural plant product precursors …”

Occurrence of Marine Ingredients in Fragrance: Update on the State of Knowledge

“…Thus, ambrafuran has been synthesized from monoterpenes, sesquiterpenes and diterpenes [226]. The main monoterpenes used for the synthesis of ambrafuran are carvone [227] and thujone [228]. Regarding sesquiterpenes, nerolidol [229,230], β-farnesene [231] and drimenol [232] have been used as starting reagents.…”

“…Chemistry 2021, 3, FOR PEER REVIEW 14 terpenes used for the synthesis of ambrafuran are carvone [227] and thujone [228]. Regarding sesquiterpenes, nerolidol [229,230], β-farnesene [231] and drimenol [232] have been used as starting reagents.…”

Solvent-Driven Selectivity on the One-Step Catalytic Synthesis of Manoyl Oxide Based on a Novel and Sustainable “Zeolite Catalyst–Solvent” System

“…Both C13 MO epimers are valuable compounds as they have been proven to be an antibacterial agents against Staphylococcus aureus, Pseudomonas aeruginosae and Klebsiella pneumonia [7], as well as to have antimicrobial activity against Borrelia burgdorferi [8] and against Gram-positive bacteria (B. cereus, Str.faecalis, St. aureus, St. epidermidis, and B. subtilis) [9]. Furthermore, 13R-MO has been reported as a potential precursor of two valuable compounds forskolin [6,10,11] and ambrox [12][13][14] (Scheme 2). These two compounds have received much attention for their broad range of applications [13][14][15][16][17][18][19][20][21].…”

“…Furthermore, 13R-MO has been reported as a potential precursor of two valuable compounds forskolin [6,10,11] and ambrox [12][13][14] (Scheme 2). These two compounds have received much attention for their broad range of applications [13][14][15][16][17][18][19][20][21]. In particular, the limited availability of pure forskolin is currently hindering its full utilization; therefore, a new and sustainable strategy is needed for forskolin production.…”