1,3-Bis(carboxymethyI)imidazole was identified in a model reaction mixture derived from glycine, glyoxal, and formaldehyde. The same compound was also found in the reaction of glycine with glyoxal. The structure of this compound was elucidated from the measured molecular, mass and 'H-NMR and 13C-NMR spectral data and confirmed by X-ray crystallographic measurements. Similarly, a 2-methyl-, 4-methyl-, and 2,4-dimethyl-1,3-bis(carboxymethyl)-imidazole were formed in reactions of glycine with glyoxal or methylglyoxal and formaldehyde or acetaldehyde. These 1,3-symmetrically substituted imidazoles represent quite a new group of N-containing heterocyclic compounds originating in model systems containing amino acids and a-dicarbonyl compounds and probably also in natural systems.

The 13C NMR spectra of eleven hydroxy and 0x0 derivatives of methyl esters of 1-and 4diamantane carboxylic acids, three hydroxy derivatives of diamantanone and six dibromo derivatives of diamantane have been measured in CDCI, or C6D6 solutions. The signals were assigned by the additivity rule. The "C NMR spectra of all compounds were described by two parameters, e.g. the sum of the 13C chemical shifts of all carbon atoms in the measured compounds (SCCS) and the ratio of the number of carbon atoms (w) and theoretical number of signals (MI.

Action of strongly basic reagents on methyl Nα-benzyloxycarbonylamino-γ-bromobutyrate leads to 1-aminocyclopropanecarboxylic acid derivatives whose structure was determined by 1H NMR, 13C NMR and IR spectroscopy. According to IR spectroscopy, the urethane CO-NH group in crystalline methyl 1-benzyloxycarbonylaminocyclopropanecarboxylate exists in the cis(E) conformation which on dissolution is transformed into the trans(Z) form. NMR spectroscopy showed that the acid-catalyzed esterification of α-amino-γ-bromobutyric acid is accompanied by replacement of the covalently bonded bromine by chlorine.

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