Total synthesis of (−)-lentiginosine

Recent Developments in the Synthesis of Pyrrolidine‐Containing Iminosugars

“…[101] Here, dioxa-spiro derivative 182, obtained from cyclohexylidene protected glyceraldehyde, was alkylated and deprotected to give the alkynediol 183. Reduction to the alkene 184 and "mismatched" Sharpless asymmetric epoxidation then yielded epoxydiol 185 with syn selectivity (≈ 20:1, syn/anti).…”

Enantioselective synthesis of polyhydroxyindolizidinone and quinolizidinone derivatives from a common precursor

“…Ring-size variation and/or stereochemical manipulation of the hydroxy groups have been adequately practiced for such purpose [ 16 – 17 ]. Indolizidines and quinolizidines with fewer hydroxy groups such as lentiginosine ( 3 ) [ 18 – 19 ] and lupinine ( 4 ) [ 20 ] also display a useful level of biological activities. For this, and other reasons, several novel methodologies have been developed towards the synthesis of polyhydroxylated indolizidine and quinolizidine derivatives as analogues of natural products which involved RCM [ 21 – 24 ], dipolar cycloaddition [ 25 – 26 ], nucleophilic substitution [ 27 – 28 ], diazo insertion [ 29 ], ring expansion–transannular cyclization [ 30 ], Cope–House cyclization [ 31 ], etc.…”

Hydroxyl-Substituted Ladder Polyethers via Selective Tandem Epoxidation/Cyclization Sequence

“…20 The reaction required stoichiometric Ti(O i -Pr) 4 to achieve complete conversion, as has been observed in the epoxidation of 1,2-diols. 21 Under these conditions, desired tricycle 10 was isolated in 74% yield as the sole product.…”