An approach to total synthesis of (+)-lycoricidine
摘要:
A convergent synthesis of a protected version of (+)-lycoricidine has been accomplished in 13 steps from L-arabinose. Preparation of the aminocyclitol moiety 50 employed a novel vinylsilane-terminated N-sulfonyliminium ion cyclization of vinylsilane aldehyde 42. Closure of the B-ring using an intramolecular Heck reaction afforded lycoricidine derivative 58. An unexpected cyclization of vinylsilane aldehyde 42 allowed for the stereodivergent preparation of semiprotected conduritols 43 and 45.
A strategy for synthesis of conduritols and related cyclitols via stereodivergent vinylsilane-aldehyde cyclizations
摘要:
A novel stereospecific and stereodivergent cyclization of vinylsilane-aldehyde 10, derived from L-arabinose, has been used to prepare the scalemic protected conduritols 11 and 12.