Vinylsulfone-modified carbohydrates: first general route to d-lividosamine (2-amino-2,3-dideoxy-d-glucose) and its new analogues
摘要:
A general route to D-lividosamine and its new analogues has been devised for the first time. The essence of the present synthetic route lies in the diastereoselective introduction of N-monoalkylated and N-dialkylated amines to C-2 carbons of methyl 2,3-dideoxy-3-C-phenylsulfonyl-alpha -D-hex-2-enopyranoside and methyl 2,3-dideoxy-3-C-phenylsulfonyl-P-D-hex-2-enopyranoside in equatorial configurations. The 2-amino-2,3-didcoxysugrs thus generated, are desulfonated reductively at C-3 sites to produce a known intermediate for the synthesis of D-lividosamine and several new 2-N-alkylamino- acid 2-N,N-dialkylamino-2,3-dideoxy analogues. (C) 2001 Elsevier Science Ltd. All rights reserved.
Comparison of the two anomers of methyl 2-(N-benzylamino)-2,3-dideoxy-4,6-O-phenylmethylene-3-C-phenylsulfonyl-D-glucopyranoside
摘要:
The title compounds, the alpha and beta anomers of methyl 2-(N-benzylamino)-2,3-dideoxy-4,6-O-phenylmethylene-3-C- phenylsulfonyl-D-glucopyranoside, C27H29NO6S, belong to the class of deoxyamino-sugars prepared by the addition of amines at C2. The endocyclic bond lengths of the pyranose ring in the alpha anomer are shorter than the corresponding bonds in the alpha anomer. The pyranose ring is in the chair form in the former, while it is in the boat form in the latter. These observed differences could be attributed to the C2 substitution of a bulky group. The phenylsulfonyl and benzylamino groups are in equatorial positions in the alpha anomer, while the benzylamino group is axial in the beta anomer.