The synthesis of polyoxygenated, enantiomerically pure cyclopentane derivatives on route to neplanocin A stereoisomers via alkylidenecarbene species prepared from sugar templates.
Our new method for the generation of alkylidenecarbenes, based on the reaction of trimethylsilylazide/Bu(2)SnO with alpha-cyanomesylates, has been applied to the synthesis of enantiomerically pure polyhydroxylated cyclopentane derivatives from conveniently functionalized sugar intermediates prepared from D-mannose. The stereoselectivity of the 1,5 C-H insertion reaction leading to the major trans-isomers (8a,b) has been assigned by (1)H RMN spectroscopic data, and correctly rationalized by a computational analysis at DFT level. Compounds 8a and 8b have been designed as suitable intermediates for the synthesis of neplanocin A enantiomer.
Nguyen Van Nhien
Albert
A
Laboratoire des Glucides UMR6219, Université de Picardie Jules Verne, Faculté des Sciences, 33, rue Saint Leu, 80039 Amiens, France. albert.nguyen-van-nhien@u-picardie.fr
Soriano
Elena
E
Marco-Contelles
José
J
Postel
Denis
D
D000241:Adenosine / Q000031:analogs & derivatives* / Q000737:chemistry; D002241:Carbohydrates / Q000737:chemistry*; D003517:Cyclopentanes / Q000138:chemical synthesis* / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D010100:Oxygen / Q000737:chemistry*; D011789:Quantum Theory; D013237:Stereoisomerism
D002241:Carbohydrates; D003517:Cyclopentanes; C030011:carbene; C031096:neplanocin A; D000241:Adenosine; D008697:Methane; D010100:Oxygen