404346-81-2Relevant academic research and scientific papers
Synthesis of trihydroxylated pyrrolizidine using 1,3-Dipolar cycloaddition of D-erythrose derived nitrone
Kubáň,Kolarovi?,Fi?era,J?ger,Humpa,Prónayová
, p. 1866 - 1868 (2001)
A route has been developed for the synthesis of enantiomerically and diastereomerically pure trihydroxylated pyrrolizidines. A chiral sugar derived nitrone undergoes diastereoselective dipolar cycloaddition with methyl acrylate to afford erythro-cis isoxazolidine; a suitable cycloadduct undergoes N-O cleavage and recyclization to (1S,2R,6R,7aS)-trihydroxylated pyrrolizidine.
Stereoselectivity of 1,3-dipolar cycloadditions of D-erythrose and D-threose derived nitrones with methyl acrylate
Kubáň,Kolarovi?,Fi?era,J?ger,Humpa,Prónayová,Ertl
, p. 1862 - 1865 (2001)
1,3-Dipolar cycloadditions between the D-erythrose and D-threose derived nitrones and methyl acrylate proceed in a regiospecific manner to afford the corresponding 3,5-disubstituted diastereomeric isoxazolidines in good yields. The stereoselectivity was dependent on the steric hindrance of the nitrone. The major products were found to have the C-3/C-4′ erythro and C-3/C-5 cis relative configuration. Its formation can be rationalized by less hindered endo attack of the Z-nitrone in an antiperiplanar manner with respect to the largest group of the cyclic acetal.
