Novel Methyl 4,6-O-benzylidene-3-ketoglucopyranosid-fused γ-lactam: Synthesis and Crystal Structure

Abstract

The title compound methyl 4,6-O-benzylidene-3-ketoglucopyranosid-fused γ-lactam was synthesized from 2-oxoglucopyranoside in one pot via multi-step reaction sequence under mild conditions. It was characterized by HRMS, 1H and 13C-NMR, IR, elemental analysis and single crystal X-ray diffraction. The crystal belongs to orthorhombic P2(1)2(1)2(1) space group with unit cell parameters a = 6.1840 (12) A, b = 10.372 (2) A, c = 25.702 (5) A, V = 1648.5 (6) A3, Z = 4, Dc = 1.343 Mg/m3, λ = 0.71073 A, μ(Mo Kα) = 0.102 mm−1, F(000) = 704. X-ray diffraction analysis reveals that the compound adopts chair-chair conformation. The newly formed γ-lactam moiety is fused to glucopyranoside ring by C2 to form spirosugar. The crystal structure is stabilized by N–H···O2 hydrogen bond. Novel methyl 4,6-O-benzylidene-3-ketoglucopyranosid-fused γ-lactam was synthesized and characterized by HRMS, 1H and 13C-NMR, IR, elemental analysis and single crystal X-ray diffraction.