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J Org Chem
; 67(4): 1290-6, 2002 Feb 22.
Article
in English
| MEDLINE
| ID: mdl-11846676
ABSTRACT
A concise enantioselective synthesis of (S)-(-)-xylopinine (1) is described involving the addition of the laterally lithiated derivative of o-tolunitrile of 16 to enantiopure sulfinimine (+)-14. Treatment of the resulting cyano sulfinamide adduct (-)-17b with DIBAL-H accomplishes five operations in a single pot and furnishes the cyclic imine (+)-18 in good yield. Reduction and cyclization affords (S)-(-)-1. Alternatively basic hydrolysis of 17b,c gives isoquinolone 21 that is cyclized and reduced to give (S)-(-)-1.
Subject(s)
Berberine Alkaloids/chemical synthesis , Imines/chemistry , Sulfur Compounds/chemistry , Berberine Alkaloids/chemistry , Chromatography, Thin Layer , Cyclization , Magnetic Resonance Spectroscopy , Molecular Structure , Spectroscopy, Fourier Transform Infrared , Stereoisomerism
2.