Table 5.
Structural characteristics and pharmaceutical properties of DAI, D3 and D4.
| characteristics and properties |
DAIa | DD4 | DD5 | |
|---|---|---|---|---|
| relative molecular mass | 254 | 458 | 472 | |
| melting point (°C) | 315–323 (decompose) | 144–146 | 151–153 | |
| crystal shape | crystallized powder | crystallized powder | crystallized powder | |
| solubility in water (μg ml−1) | —b | —b | —b | |
| solubility in ethyl acetate (μg ml−1) | 0.13 ± 0.11 | 36 302 ± 4660 | 28 115 ± 1151 | |
| apparent lipid-hydro partition coefficient | calculated valuec | 2.73 | 5.39 | 5.74 |
| found | —b | —b | —b | |
| molecular polar surface area/two-dimensional (Å2) | calculated valuec | 66.76 | 78.90 | 78.90 |
| molecular surface area/three-dimensional (Å2) | calculated valuec | 315.07 | 589.83 | 620.77 |
| dissociation constantd (%) | calculated valuec | 10.41 | 100 | 100 |
| polarizability | calculated valuec | 26.21 | 49.68 | 51.52 |
| refractivity | calculated valuec | 69.70 | 123.54 | 128.28 |
| H-bondc | donor site/count | 2/2 | 0/0 | 0/0 |
| accepter site/count | 5/4 | 10/5 | 10/5 | |
| absorptivity (%) | 20.29 | 87.97 | 90.34 | |
aStructural characteristics of DAI can be found in [16].
bCannot be detected.
cAt pH 7.4, 410 K.
dPercentage of drug prototypes.