54351-43-8Relevant articles and documents
Conversion of Unprotected Aldose Sugars to Polyhydroxyalkyl and C-Glycosyl Furans via Zirconium Catalysis
Ronaghi, Nima,Fialho, David M.,Jones, Christopher W.,France, Stefan
, p. 15337 - 15346 (2020)
An efficient, zirconium-catalyzed conversion of unprotected aldose sugars with acetylacetone to polyhydroxyalkyl furans or C-glycosylfurans is reported. The furan products are formed in up to 93% yield using 5-10 mol % ZrCl4. Pentoses are readily converted at room temperature, while hexoses and their oligosaccharides require mild heating (i.e., 50 °C). Efficient conversions of glycolaldehyde, glyceraldehyde, erythrose, a heptose, and glucosamine are also demonstrated. This approach outpaces each of the previous Lewis acid-catalyzed methods in at least one the following ways: (i) lower catalyst loadings; (ii) reduced reaction temperatures; (iii) shorter reaction times; (iv) equimolar substrate stoichiometry; (v) expanded sugar scope; (vi) higher selectivities; and (vii) the use of an Earth-abundant Zr catalyst.
Synthesis of New N-alkyl-5-formyl-2-methylpyrrole Derivatives from Glucosamine
Tao, Tao,Zhao, Hua Xin,Ji, Xiao Ming,Lai, Miao,Zhao, Ming Qin
, p. 943 - 945 (2018/02/22)
Glucosamine hydrochloride 1 was treated with 1,3-dicarbonyl compounds to obtain 2-methyl-5-(1,2,3,4-tetrahydroxy-butyl) pyrrole 2a and 2b, respectively. Under the role of NaIO4, 2a and 2b were successfully transformed into the related 5-formal pyrrole derivative 3a and 3b, respectively. Compounds 4a–4d and 5a–5e were obtained by reacting 3a and 3b with chlorinated hydrocarbons by alkylation reactions, respectively. The structures of all new products were confirmed by IR, NMR, and HRMS spectra.
