Total synthesis of microginin, an angiotensin-converting enzyme inhibitory pentapeptide from the blue-green alga Microcystis aeruginosa
摘要:
Microginin, an angiotensin-converting enzyme inhibitory peptide isolated form the blue-green alga Microcystis aeruginosa, and its three diastereoisomers were efficiently synthesized, which unequivocally established the absolute stereostructure of microginin to be 1d.
Total synthesis of microginin, an angiotensin-converting enzyme inhibitory pentapeptide from the blue-green alga Microcystis aeruginosa
摘要:
Microginin, an angiotensin-converting enzyme inhibitory peptide isolated form the blue-green alga Microcystis aeruginosa, and its three diastereoisomers were efficiently synthesized, which unequivocally established the absolute stereostructure of microginin to be 1d.
Lewis acid-promoted electron transfer deoxygenation of epoxides, sulfoxides, and amine N-oxides: the role of low-valent niobium complexes from NbCl5 and Zn
作者:Kyungsoo Oh、William Eric Knabe
DOI:10.1016/j.tet.2009.02.013
日期:2009.4
A mild and operationally simple deoxygenation of epoxides, sulfoxides, and amine N-oxides is described using a sub-stoichiometric amount of low-valent niobium complexes generated in situ from commercially available NbCl5 and zinc dust. The deoxygenation proceeds by a reductive cleavage of polarized O–C/O–N/O–S bonds through a single electron transfer from zinc metal to the niobium–substrate complex
A simple route to syn α-Amino-β-Hydroxy esters by C-2 regioselective opening of a, β-Epoxy esters with metal halides
作者:Giuliana Righi、Giovanna Rumboldt、Carlo Bonini
DOI:10.1016/0040-4020(95)00873-7
日期:1995.11
α,β-Epoxyesters are opened by NaX (X = I, Br) in a regio and stereoselective fashion to β-hydroxy-α-halo esters, which represent suitable precursors of synα-amino-β-hydroxyesters and β-hydroxy esters.
Highly enantioselective reduction of 3-chloro-2-oxoalkanoates with fermenting bakers' yeast. A new synthesis of optically active 3-chloro-2-hydroxyalkanoates and glycidic esters
Reduction of 3-chloro-2-oxoalkanoic esters with fermenting bakers' yeast gave optically active 3-chloro-2-hydroxyalkanoic esters 2 (anti(2S,3R)/syn (2S,3S) = 52:48-90:10) in 50-85% yields with >95% ee except for 43% ee of ethy syn-(2S,3S)-3-chloro-2-hydroxy-4 phenylbutanoate (2j). Compounds 2 were treated with NaOEt to give (E)-(2R,3S)-2,3-epoxyalkanoates 3 in 30-66% yields with 44-64% ee. Optically active 2,3-epoxy alcohols (cis-23, trans-23, and trans-25), key intermediates for the syntheses of (-)-disparlure (4), mosquito pheromone (5), and a component of passion fruit flavor (6), were prepared with more than 86% ee in high yields.
Total synthesis of microginin, an angiotensin-converting enzyme inhibitory pentapeptide from the blue-green alga Microcystis aeruginosa
Microginin, an angiotensin-converting enzyme inhibitory peptide isolated form the blue-green alga Microcystis aeruginosa, and its three diastereoisomers were efficiently synthesized, which unequivocally established the absolute stereostructure of microginin to be 1d.