The synthesis of (11R,12S)-lactobacillic acid and its enantiomer

The absolute configuration of methyl dihydrosterculate: an unusual phytofatty acid isolated from the seed oil of Litchi chinensis

“…The validity of TocanneÕs configurational assignments for 5 and 6 has recently been confirmed through the total synthesis of the enantiomers of the parent cyclopropyl fatty acid. 12 Based on these considerations, it is clear that 1 isolated from Litchi bears the (R)-configuration at C-9 and (S)-configuration at C-10. Interestingly, this material is the enantiomer of dihydrosterculate, previously isolated from Lactobacillus plantarum cultures grown in a medium containing oleate.…”

Total syntheses of cis-cyclopropane fatty acids: dihydromalvalic acid, dihydrosterculic acid, lactobacillic acid, and 9,10-methylenehexadecanoic acid

“…[α] 25 D +22.9 (c 0.251, CHCl 3 ) (lit. 22 +23.1). 1 H NMR (CDCl 3 , 400 MHz) δ 3.55-3.67 (2 H, m), 1.05-1.52 (15 H, m), 0.83-0.86 (1 H, m), 0.88 (3 H, t, J = 6.8 Hz), 0.67-0.73 (1 H, m), −0.04 (1 H, q, J = 4.8 Hz); 13…”

“…Minnikin and co-workers reported the synthesis of both enantiopodes of enantiopure lactobacillic acid 4 by bidirectional elaboration of a homo-chiral cyclopropane linchpin, which was derived from lipasemediated desymmetrization of cis-cyclopropane-1,2-dimethanol or by diastereoselective Simmons-Smith cyclopropanation of a D-mannitol-derived alkene. 21,22 Kobayashi and co-workers reported a related approach to both enantiomers of cis-9,10methylenehexadecanoic acid 1 involving bidirectional Wittig extension of an enzymatically-derived homochiral cyclopropaγ-lactone. 16 Manthorpe and co-workers have reported the synthesis of enantiopure 9R,10S-dihydrosterculic acid 3 with the key step involving the Corey-Chaykovsky cyclopropanation of a homochiral alkylidene bis(sulfoxide).…”

The Synthesis of Single Enantiomers of α-Mycolic Acids of Mycobacterium­ tuberculosis and Related Organisms, with Alternative­ Cyclopropane Stereochemistries

“…The (1S,2R)-aldehyde 3 was prepared by a method described earlier from (1S,2R)-butyryloxymethyl-2-formylcyclopropane. 28,30,31 Reaction of (1R)-butyryloxymethyl-(2S)formyl-cyclopropane 5 with sulfone 4 in a similar way (Scheme 2) led to the (1R,2S)-aldehyde 6.…”