151526-81-7Relevant articles and documents
A novel synthesis of (+)-biotin from L-cysteine
Seki, Masahiko,Mori, Yoshikazu,Hatsuda, Masanori,Yamada, Shin-ichi
, p. 5527 - 5536 (2007/10/03)
(+)-Biotin (1) was synthesized in 25% overall yield over 11 steps from L-cysteine. The contiguous asymmetric centers at C-3a and C-6a were formed through a novel and highly stereoselective Lewis base-catalyzed cyanosilylation of α-amino aldehyde 3 to provide anti- O-TMS-cyanohydrin 4 with high stereoselectivity and in high yield (anti/syn = 92:8, 96%). Treatment of 4 with a di-Grignard reagent, 1,4-bis(bromomagnesio)butane, followed by carbon dioxide, efficiently installed the 4-carboxybutyl chain at C-4 to give keto acid 5. The final cyclization to bicyclic compound 7b, a precursor to 1, was realized by a palladium-catalyzed intramolecular allylic amination of cis-allylic carbonate 6b that was elaborated from 5.
A Novel Enantioselective Synthesis of (+)-Biotin
Deroose, Frederik D.,Clercq, Pierre J. De
, p. 4365 - 4368 (2007/10/02)
A conceptually simple enantioselective 14-step synthesis of (+)-biotin from L-cysteine is reported based upon an intramolecular 1,3-dipolar cyclodaddition sequence involving (i) elimination of bromide 8 to the endocyclic thioenol ether 9, (ii) thermolysis of the ene carbamoyl azide 9 to the exocyclic thioenol ether 10.Both the synthesis of 8 and the final transformation of 10 into (+)-biotin are based upon literature precedents.