Synthesis, crystal structure and conformation of N-acetyl-Cα,α-diethylglycine-N′-methylamide

Research paper by Zdzisław Gałdecki, Bernard Luciak, Krzysztof Kaczmarek, Mirosław T. Leplawy, Adam S. Redliński

Indexed on: 01 Nov '92Published on: 01 Nov '92Published in: Monatshefte für Chemie - Chemical Monthly


Synthesis and X-ray structure analysis of N-acetyl-α,α-diethylglycine-N′-methylamide [CH3-Co-NH-C(C2H5)2-CO-NHCH3] are described. The compound was obtained from the corresponding N-acetyl derivative [CH3-CO-NH-C(C2H5)2-COOH] through the mixed anhydride procedure. It crystallizes as monohydrate (C9H18N2O2·H2O) in space group P21/c,a=7.139(1),b=11.823(2),c=15.778(3) Å, β=122.23(1)°,V=1126.53 Å3,Dm=1.20 Mgm−3 (room temperature),R=0.046 for 1523 reflections. The crystal packing is dominated by two strong hydrogen bonds between the water molecule and two carbonyl oxygen atoms and two weak H-bonds to two amide-N-atoms of symmetry-equivalent molecules. The molecular conformation is closer to a 310-helix then ana-helix.