title: Enantioselctive syntheses of sulfur analogues of flavan-3-Ols.
abstract: The first enantioselective syntheses of sulfur flavan-3-ol analogues 1-8 have been accomplished, whereby the oxygen atom of the pyran ring has been replaced by a sulfur atom. The key steps were: (a) Pd(0) catalyzed introduction of -S t-butyl group, (b) Sharpless enantioselective dihydroxylation of the alkene, (c) acid catalyzed ring closure to produce the thiopyran ring, and (d) removal of benzyl groups using N,N-dimethylaniline and AlCl(3). The compounds were isolated in high chemical and optical purity.
authors: Chemical Process Research & Development and Analytical Development, Johnson Matthey Pharmaceutical Materials Inc., Devens, MA 01434, USA. sharmap76@yahoo.com
authors: Pradeep K
authors: PK
authors: Sharma
authors: Min
authors: M
authors: He
authors: Jurjus
authors: J
authors: Jurayj
authors: Da-Ming
authors: DM
authors: Gou
authors: Richard
authors: R
authors: Lombardy
authors: Leo J
authors: LJ
authors: Romanczyk
authors: Hagen
authors: H
authors: Schroeter
mesh_terms: D003500:Cyclization; D005419:Flavonoids / Q000138:chemical synthesis* / Q000737:chemistry*; D012399:Rotation; D013237:Stereoisomerism; D013457:Sulfur Compounds / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: D005419:Flavonoids; D013457:Sulfur Compounds; C404987:flavan-3-ol