The crystal and molecular structure of phosphoenolpyruvic acid

Phosphoenolpyruvic acid crystals, obtained by slow concentration of an aqueous solution, are triclinic, space group P1, with a = 5.905(5), b = 8.135(8), c = 14.095(15) A, alpha = 104.70(8), beta = 97.72(8), gamma = 100.99(8) degrees, and Z = 4. Two crystallographically independent phosphoenolpyruvic acid molecules differ in the orientation of the phosphate group relative to the enolpyruvate moiety. The phosphate groups have different tetrahedral distortions, and their P-O(ester) bond-lengths are 1.578(3) and 1.583(3) A. All OH groups are involved in intermolecular hydrogen bonds.

A new type of crown ether. III. Triethylene glycolic diester of naphthalene dithioglycolic acid

The structure of 2,7-(11,22-diono-12, 15,18.21-tetroxa-9,24-dithia)-hexadecylene-naphthalene was investigated by 1H and 13C nmr and mass spectrometry. An X-ray structural investigation indicated the dissymmetric ansa structure of this compound in the crystalline state.

Inhibition of immune response by diisopropyl phosphorofluoridate

Effect of acute, oral intoxication of guinea-pigs and pigs with diisopropyl phosphorofluoridate (DFP) on the level of humoral factors of natural immunity and immunocyte production was studied. The effect of DFP on these animals, expressed by decreased complement and haemolysin activities and diminished number of plaque-forming cells (PFC), was observed only after repeated intoxication. After a single application of DFP statistically significant increase of these parameters were found. In single and multiple treatments, lysozyme activity was somewhat weaker in comparison with control animals.