title: Synthesis of the spiroiminal moiety and approaches to the synthesis of marineosins A and B.
abstract: A short and efficient synthesis of model spiroiminals that have the same stereochemistry as marineosins A and B, but different conformations, was carried out in six or seven steps from 6-methyltetrahydropyran-2-one. These spiroiminals were also prepared biomimetically by reduction of an enol ether. A more highly substituted spiroiminal with the same stereochemistry and conformation as marineosin A was prepared in 11 steps from parasorbic acid. A macrocyclic pyrrole lactone was prepared stereospecifically in 10 steps. A five-step sequence converted the lactone to a late hemi-iminal intermediate that has resisted the methylation and spiroiminal formation that would lead to marineosin A.
authors.affiliation: Department of Chemistry, Brandeis University , MS 015, Waltham, Massachusetts 02454-9110, United States.
authors.forename: Xiao-Chuan
authors.initials: XC
authors.lastname: Cai
authors.forename: Barry B
authors.initials: BB
authors.lastname: Snider
mesh_terms: D015394:Molecular Structure; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D013141:Spiro Compounds