Hydrogen-bond motifs in N-monosubstituted derivatives of barbituric acid: 5-allyl-5-isopropyl-1-methylbarbituric acid (enallylpropymal) and 1,5-di(but-2-enyl)-5-ethylbarbituric acid.
Both title structures exhibit essentially planar barbiturate rings. The crystal structure of enallylpropymal (5-allyl-5-isopropyl-1-methylbarbituric acid), C(11)H(16)N(2)O(3), is composed of centrosymmetric N-H...O hydrogen-bonded dimers, while 1,5-di(but-2-enyl)-5-ethylbarbituric acid, C(14)H(20)N(2)O(3), forms N-H...O hydrogen-bonded helical chains. Each of the ten known crystal structures of closely related N-monosubstituted derivatives of barbituric acid displays one of the fundamental N-H...O hydrogen-bonded motifs of the two title structures, i.e. either a dimer or a chain.
Gelbrich
Thomas
T
Institut für Pharmazie, Universität Innsbruck, Innrain 52, 6020 Innsbruck, Austria. thomas.gelbrich@uibk.ac.at
Zencirci
Neslihan
N
Griesser
Ulrich J
UJ
D001463:Barbiturates / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular
C547122:1,5-di(but-2-enyl)-5-ethylbarbituric acid; D001463:Barbiturates; C547121:5-allyl-5-isopropyl-1-methylbarbituric acid; C032232:barbituric acid