Synthesis 2010(5): 749-756  
DOI: 10.1055/s-0029-1218628
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Highly Stereoselective Synthesis of 2-Amino-3-C-methyl-2,3-dideoxyaldoses by C3-Chain Elongation via Homoaldol Reaction of Sugar Aldehydes

Sabine Kollmann, Roland Fröhlich, Dieter Hoppe*
Westfälische Wilhelms-Universität Münster, Organisch-Chemisches Institut, Corrensstrasse 40, 48149 Münster, Germany
Fax: +49(251)8336531; e-Mail: dhoppe@uni-muenster.de;
Further Information

Publication History

Received 11 September 2009
Publication Date:
04 January 2010 (online)

Abstract

A flexible strategy for the stereoselective synthesis of branched amino sugar analogues is described. It is based on a C3-chain elongation of suitable protected aldoses. By using the sequence homoaldol reaction, epoxidation, and methanolysis α-methyl allo-furanosides are obtained. Proximate amination of the corresponding triflates afford the title compounds. All reactions proceed with high yield, high diastereoselectivities, and allow for a broad application.

1

X-ray crystal structure analysis.

7

A research in Scifinder afforded no hit.

16

X-ray crystal structure analysis of 7c: Formula C17H28O8, M = 360.39, colorless crystal 0.30 × 0.20 × 0.10 mm, a = 10.0328(3), b = 9.4646(3), c = 10.1594(3) Å, β = 106.772(2)˚, V = 923.66(5) ų, ρcalc = 1.296 g cm, µ = 0.861 mm, empirical absorption correction (0.782 ≤ T ≤ 0.919), Z = 2, monoclinic, space group P21 (No. 4), λ = 1.54178 Å, T = 223 K, ω and φ scans, 5102 reflections collected ± h, ± k, ± l), [(sin θ)/λ] = 0.60 Å, 2615 independent (R int = 0.030) and 2563 observed reflections [I ≥ 2 σ (I)], 233 refined parameters, R = 0.034, wR ² = 0.089, Flack parameter -0.10 (19), max. residual electron density 0.14 (-0.18) e Å, hydrogen atoms calculated and refined as riding atoms.

17

Data set was collected with a Nonius KappaCCD diffractometer. Programs used: data collection COLLECT,¹8 data reduction Denzo-SMN,¹9 absorption correction Denzo,²0 structure solution SHELXS-97,²¹ structure refinement SHELXL-97,²² and graphics Mopict.²³

24

CCDC 747428 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge at www.ccdc.cam.ac.uk/conts/retrieving.html [or from the Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44(1223)336033, E-mail: deposit@ccdc.cam.ac.uk].