Brunetti, Bruno published the artcileSublimation Enthalpies of Some Methyl Derivatives of Uracil from Vapor Pressure Measurements, Safety of 3-Methylpyrimidine-2,4(1H,3H)-dione, the publication is Journal of Chemical and Engineering Data (2000), 45(2), 242-246, database is CAplus.
The standard sublimation enthalpies for uracil, 1-methyluracil, 3-methyluracil, and 1,3-dimethyluracil, ΔsubH°(298 K) = (128 ± 2), (124 ± 5), (121 ± 4), and (118 ± 4) kJ mol-1, resp., were determined from their vapor pressures measured by the torsion method. The results of vapor pressure measurements were fit to the following linear equations: uracil, log(p/kPa) = (12.29 ± 0.15) – (6634 ± 100) K/T (from 384 K to 494 K); 1-methyluracil, log(p/kPa) = (13.75 ± 0.15) – (6357 ± 150) K/T (from 343 K to 428 K); 3-methyluracil, log(p/kPa) = (13.59 ± 0.10) – (6210 ± 100) K/T (from 344 K to 419 K); 1,3-dimethyluracil, log(p/kPa) = (15.10 ± 0.10) – (6049 ± 100) K/T (from 311 K to 364 K). The different sublimation behavior of some compounds can be due to the presence of hydrogen bonds in their solid state.
Journal of Chemical and Engineering Data published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Safety of 3-Methylpyrimidine-2,4(1H,3H)-dione.
Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia