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6-[Bis(ethoxycarbonyl)methyl]-6-deoxy-1,2;3,4-di-O-isopropyl-idene-d-galacto-pyran-ose.

Acta Crystallographica Section E Structure Reports Online (Impact Factor: 0.35). 01/2010; 66(Pt 12):o3217-8. DOI:10.1107/S1600536810046921
Source: PubMed

ABSTRACT The title compound, C(19)H(30)O(9), was prepared by substitution at the C6 position in 1,2;3,4-di-O-isopropyl-idene-6-O-trifluoro-methane-sulfonyl-d-galactose using sodium eth-oxy-malonate in dimethyl-formamide. The conformation is skew-boat (0)S(2), slightly distorted towards boat B(2,5). The inflexible pyran-ose structure makes the title compound a suitable inter-mediate for further synthetic work by keeping stereogenic carbon atoms safe from inversion. Several short intra-molecular C-H⋯ O contacts may stabilize the conformation of the mol-ecule. Inter-molecular C-H⋯O inter-actions also occur.

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