Beckmann rearrangement of erythromycin A 9(￡')-oxime (1) generates erythromycin A 6,9-imino ether (2) which has been characterized by NMR, IR, MS and elemental analysis. Crystal structure of 2 was determined by X-ray single crystal diffraction study. The crystal of erythromycin A 6,9-imino ether belongs to orthorhombic system and space group P2_12_12_1 with parameters: a = 1.0646(2) nm, h = 1.7896(4) nm, c = 2. 3755(5) nm, α=β=γ= 90.00(0)°, 7 = 4.5257(16) nm~3, Do = 1.187 g/cm~3, Z = 4, F(000) = 1776, μ=0.091 mm~(-1), R_1 = 0.0399, wR_2 = 0.0482.

Key words: ERYTHROMYCINUM;imino ether;REARRANGEMENT REACTION;CRYSTAL STRUCTURE, OXIME;XRD;STRUCTURE CHARACTERISTICS