Biltz

The study of the iV-alkyl derivatives of allantoxaidine was taken up by Biltz who proceeded from its formerly accepted hydantoin structure and obtained its monomethyB and dimethyB derivatives. 

Final structure determination of the monomethyl derivatives was made possible only on performing straightforward syntheses of the compounds, analogous to syntheses of allantoxaidine. The 1-methyl (19) and 3-methyl (20) derivatives were prepared by cyclization of 1- and 3-methyl biuret,respectively. The 3-methyl derivative was also obtained by cyclization of A ,A -bis(methylcarbamyl)formami-dxne. The 1-methyl derivative was the same as the product obtained by Biltz on methylation of silver salt of allantoxaidine with methyl iodide. The same product is formed primarily during methylation of dioxotriazine with diazomethane. An excess of this agent produces the expected 1,3-dimethyl derivative (21). These results of alkyl-... 

The structure (5) originally proposed by Ponomarev appeared to be confirmed by the conversion of dihydrooxonic acid to allantoin performed by Biltz and Giesler. Biltz and RobP showed later that oxonic acid is identical with allantoxanic acid obtained on oxidation of allantoin. Since that time both these trivial names are in usage. 

In addition to the intramolecular effects, steric factors are of considerable influence. The most usual one consists of steric hindrance to attack on the lactam nitrogen atom. Certain examples of this will be given. By comparison with uracil, it would be expected that uric acid (10) would be iV-methylated in the pyrimidine ring, but that in the imidazole ring 0-methylation should also be possible. However, the experiments of Biltz and Max show that all uric acid derivatives which carry a hydrogen atom in the 9-position are converted by ethereal diazomethane into l,3,7-trimethyl-8-methoxyxanthine (11). The following are examples uric acid and its 1-methyl, 3-methyl, 7-methyl, 1,3-dimethyl, 1,7-dimethyI, 3,7-dimethyl, and 1,3,7-trimethyl derivatives. Uric acid derivatives which arc substituted by alkyl groups in the 3- and 9-positions (e.g., 3,9-dimethyl-, 1,3,9-trimethyl-, and 3,7,9-trimethyl-uric acid)do not react at all with diazomethane, possibly because of insufficient acidity. Uric acids which are alkylated... 

It is an expl, more powerful than TNT (about 133% by Ballistic Mortar), and comparable to Tetryl in sensitivity. Its Vel of Deton is 7420 m/sec at d 1.5g/cc, and 5490m/sec at d l.Og/cc. Qc is about 380kcal/mole. It is practically non-hygroscopic and its thermal stability is satisfactory. Has been used by DuPont Co as a base charge for some detonators Refs I) Beil — not found 2) H. Biltz et al, JPraktChem 142, 193-200 (1935) CA 29, 3652 (1935) 3) Anon, Report on Nitro-... 

Values quoted are from "International Critical Tables or from W. Biltz, Z. anorg. Chem., 170, 161 (1928), and D. M. Bose, Z. Physik, 65, 677 (1930). I am indebted to Mr. P. D. Brass for collecting from the literature some of the data in this table. 

Biltz, R.M. and Pellegrino, E.D. 1977 The nature of bone carbonate. Clinical Orthopaedics and Related Research 129 279-292. 

Biltz, J.A. 1995 Dietary Variability and Social Inequality at Monte Alban, Oaxaca, Mexico. Ph.D. dissertation. University of Wisconsin, Madison. 

Price, T.D. 1989 Multi-element studies of diagenesis in prehistoric bone. In Price, T.D., ed.. The Chemistry of Prehistoric Human Bone. Cambridge, Cambridge University Press 126-154. Price, T.D., Biltz, J., Burton, J.H. and Ezzo, J. 1992 Diagenesis in prehistoric bone problems and iohMiom. Journal of Archaeological Science 19 513-529. 

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