title: Selective modifications of hydrophobic vitamin B12 derivatives at c-and d-positions.
abstract: The acid-sensitivity of vitamin B(12) derived mono- and diamides was studied. It was found that the use of reductive ring-opening of the lactone moiety deactivated undesired decomposition of c-mono- and c,d-diamides under acidic conditions. As a result, reactions gave respectively c- or d-acids which were further functionalized via coupling with amino acids. Though mono- and diamides exhibited acid sensitivity, they were used for the preparation of several highly functionalized molecules showing their stability under various reaction conditions.
authors: Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
authors: Keith
authors: K
authors: ó Proinsias
authors: Maciej
authors: M
authors: Giedyk
authors: Rafał
authors: R
authors: Loska
authors: Mikołaj
authors: M
authors: Chromiński
authors: Dorota
authors: D
authors: Gryko
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D002384:Catalysis; D018360:Crystallography, X-Ray; D003958:Diamide / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D012680:Sensitivity and Specificity; D013237:Stereoisomerism; D014805:Vitamin B 12 / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D007783:Lactones; D003958:Diamide; D014805:Vitamin B 12