76335-62-1Relevant 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.,De Clercq, Pierre J.
, p. 2615 - 2618 (2007/10/02)
A conceptually attractive enantioselective 12-step synthesis of (+)-biotin from L-cysteine is reported based upon an intramolecular 1,3-dipolar cycloaddition sequence involving as key-steps (i) the macrothiolactonisation of acid 3 to Z-olefin (4), (ii) the thermolysis of the ene carbamoyl azide 5 in water with direct formation of a mixture of the benzylated derivative of (+)-biotin 6a and 6b.
