The Crystal Structure of Enniatin B

Abstract

The X-ray crystal structure of enniatin B (trigonal (hexagonal axes), a = 14.626 A, c = 16.309 A, space group R3) is described and the conformation compared to results of other investigations. In polar solvents, form P with the threefold symmetry given by the chemical formula was postulated. In this conformation the six carbonyl 0-atoms point to the inside, forming a cavity. Form P was also proposed for equimolar cation complexes in all types of solvents [3]. In nonpolar solvents form N having no symmetry was assumed from NMR studies

Revisiting the enniatins: a review of their isolation, biosynthesis, structure determination and biological activities

“…With respect to X-ray crystallography, only enniatins B ( 2 ) 34 and N ( 24 ) 15 have been reported in the literature. Alternatively, the use of NMR spectroscopy is more prominent.…”

Experimental and theoretical study on complexation of the ammonium cation with enniatin B

“…The extraction experiments were carried out in 10 mL polypropylene test-tubes with polypropylene stoppers: 2 mL of an aqueous solution of NH 4 Cl of a concentration in the range from 1 × 10 − 3 to 3 × 10 −3 mol/L and 10 kBq of 22 Na + (in the form of 22 Na + Cl − ) were added to 2 mL of a nitrobenzene solution of 1 and NaDCC, whose initial concentrations also varied from 1 × 10 − 3 to 3 × 10 − 3 mol/L (in all experiments, the initial concentration of 1 in nitrobenzene, C 1 in,nb ,was equal to the initial concentration of NaDCC in this medium, C NaDCC in,nb ).…”

“…The other chemicals used (Lachema, Brno, Czech Republic) were of reagent grade purity. The carrier-free radionuclide 22 Na + (in the chemical form of 22 Na + Cl − ) was obtained from DuPont, Belgium; its radionuclidic purity was 99.9%.…”

“…The X-ray crystal structure of free enniatin B ligand has been described by Kratky and Dobler [22]. The sandwich structure of the 2:1 complex of enniatin B with KI has been established by using X-ray diffraction [23].…”

Extraction and DFT study on interaction of the cesium cation with enniatin B

“…The X-ray crystal structure of free enniatin B ligand has been described by Kratky and Dobler [12]. The sandwich structure of the 2:1 complex of enniatin B with KI has been established by using X-ray diffraction [13].…”