The incorporation of 12-14C,(5R)-5-3Hj]MVA* and 12-14C,5-3H2]MVA into geranylgeraniol and phytoene by a preparation of 'non-aqueous' bean leaf chloroplasts has been studied. In the formation of phytoene from two molecules of geranylgeranyl pyrophosphate, the loss of hydrogen is stereospecific, the hydrogen atom lost from C-1 of each molecule of geranylgeranyl pyrophosphate being that which was ...

Comparison of crystallized MHC class II*peptide complexes has revealed that, in addition to pocket interactions involving the peptide side chains, peptide binding to MHC class II molecules is characterized by a series of hydrogen bonds between genetically conserved amino acid residues in the class II molecule and the main chain of the peptide. Many class II*peptide structures have two sets of s...

The structures of the mono- and the dihalogenated N-unsubstituted 2-aminobenzamides were characterized by means of the spectroscopic (¹H-NMR, UV-Vis, FT-IR, and FT-Raman) and X-ray crystallographic techniques complemented with a density functional theory (DFT) method. The hindered rotation of the C(O)-NH₂ single bond resulted in non-equivalence of the amide protons and therefore two distinct re...

In the planar title mol-ecule, C(16)H(16)N(2)O(4)·C(2)H(6)O, the planar Schiff base molecule is linked to the ethanol solvent mol-ecule by a hydr-oxy-amide hydrogen bond. The hydr-oxy group of the ethanol mol-ecule is a hydrogen-bond donor to the double-bonded N atom of an adjacent Sciff base, pairs of interactions taking place across a center of symmetry and giving rise to a hydrogen-bonded di...