Crystal structure of Cefadroxil

Abstract

The crystal and molecular structure of Cefadroxil, (7-[[amino-(4-hydroxyphenyl)acetyl]amino]-3-methyl-8-oxo-5-thia-1-azabicyclo-[4.2.0]oct-2-ene-2-carboxylic acid monohydrate), C₁₆H₁₇N₃-O₅S.H₂O has been determined from single crystal X-ray diffraction data. The compound crystallizes in the orthorhombic space group P2₁2₁2₁. The cell parameters are a=11.065(3), b=11.221(4) and c=14.436(4)Å; M_r=381.41; V=1792(2)ų, z=4, D_x=1.339 Mg^-3; μ=1.84 cm^-1, F(000)=752, T=296 K, R=0.037 and R_w=0.037. The β-lactam ring is not planar and the nitrogen atom in the β-lactam deviates from the plane of the other three atoms attached to it by 0.224(4)Å. The thiazene ring is in the half-chair conformation. The molecules are stabilized by N—H···O and O—H···O hydrogen bonds.