An Efficient and Stereoselective Dearylation of Asarinin and Sesamin Tetrahydrofurofuran Lignans to Acuminatolide by Methyltrioxorhenium/H2O2 and UHP Systems

• Published in: Journal of natural products (Washington, D.C.) D.C.), 2007-01, Vol.70 (1), p.39-42
• Main Authors: Saladino, Raffaele, Fiani, Cinzia, Crestini, Claudia, Argyropoulos, Dimitris S, Marini, Stefano, Coletta, Massimiliano
• Format: Article
• Language: English
• Subjects: acuminatolide; anticarcinogenic activity; asarinin; Chemistry; cultured cells; cytotoxicity; Exact sciences and technology; furans; Helichrysum; Helichrysum acuminatum; Heterocyclic compounds; Heterocyclic compounds with o, s, se, te hetero atom and condensed derivatives; humans; hydrogen peroxide; lignans; methyltrioxorhenium; Organic chemistry; Preparations and properties; sesamin; stereoisomers; urea hydrogen peroxide adduct
• ISSN: 0163-3864; 1520-6025
• DOI: 10.1021/np060479u

The synthesis of stereoisomers of acuminatolide is rare and requires complex and time-consuming multistep procedures. Asarinin (1) and sesamin (2), two diasteromeric tetrahydrofurofuran lignans, are efficiently mono-dearylated by methyltrioxorhenium (MTO, I) and hydrogen peroxide (H2O2) or urea hydrogen peroxide adduct (UHP) as primary oxidant to give (−)-(7R,8‘R,8R)-acuminatolide (3A) and (+)-(7S,8R,8‘R)-acuminatolide (3B), respectively, in high yield and diastereoselectivity (de >98%). The oxidation of 1 was also performed with novel heterogeneous catalysts based on the heterogenation of MTO on poly(4-vinylpyridine) and polystyrene resins. In these latter cases 3A was obtained with a different yield and selectivity depending on the physical−chemical properties of the support. Cytotoxic effects of 3A and 3B in mammalian cell lines in vitro are also reported.