Practical synthesis of lespedezol A1.
A practical formal synthesis of lespedezol A 1 ( 1) was accomplished in 33% yield for four steps starting from formation of the substituted chalcone. Of particular note is a useful protocol for reduction of the 2-ene bond in the isoflavone intermediate. A significant improvement in the final ring closure when water was scavenged from the reaction is also noteworthy. The ready availability of lespedezol A 1 will provide material for further pharmacological evaluation and for exploration of the pterocarpene nucleus as a potential entry into various 6a-hydroxypterocarpans.
Khupse
Rahul S
RS
Center for Drug Design and Development, Department of Medicinal and Biological Chemistry, The University of Toledo College of Pharmacy, Toledo, Ohio 43606-3390, USA.
Erhardt
Paul W
PW
D001578:Benzopyrans / Q000138:chemical synthesis* / Q000737:chemistry; D047188:Chalcones / Q000737:chemistry*; D006576:Heterocyclic Compounds, 4 or More Rings / Q000138:chemical synthesis* / Q000737:chemistry; D029884:Lespedeza / Q000737:chemistry; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000737:chemistry; D036343:Pterocarpans; D000094162:Phytoalexins
D001578:Benzopyrans; D047188:Chalcones; D006576:Heterocyclic Compounds, 4 or More Rings; C507789:6a-hydroxypterocarpan; C528146:lespedezol A1; D036343:Pterocarpans; D000094162:Phytoalexins