(Last updated December 2025)
Figure . The molecular diagram of desloratadine.
| REFCODE | GEHXEX |
|---|---|
| Formula | C19 H19 N2 Cl1 |
| Common Name | Desloratadine |
| IUPAC Systematic Name | 8-chloro-6,11-dihydro-11-(4-piperdinylidene)- 5H-benzo[5,6]cyclohepta[1,2-b]pyridine |
| Other Names | |
| CSD Refcodes | GEHXEX01, GEHXEX04, GEHXEX02 |
| Search Identifier | A |
| Scientist | Rui Guo |
| Date | December 2016 |
| Publication | Srirambhatla VK, Guo R, Dawson DM, Price SL, Florence AJ, Cryst Growth Des 2020, 20(3), 1800 DOI: Open paper (10.1021/acs.cgd.9b01522) |
| Energy model | 1 |
| Study_ID | 10 |
| Programs | CrystalPredictor (2.1.01), CrystalOptimizer (2.4), DMACRYS (2.2.0.1) |
| Location on S Drive | CHEMISTRY_CPOSS\\Desloratadine\\CrystOpt |
| Potential Description | CrystalOptimizer with GDMA2.2(PBE0/6-31G(d,p)) + FIT |
| Energy model | 2 |
| Study_ID | 30 |
| Programs | Study_ID=10, DMACRYS (2.2.0.1) |
| Location on S Drive | CHEMISTRY_CPOSS\\Desloratadine\\PCM |
| Potential Description | GDMA2.2(PCMdielectric3(PBE0/6-31G(d,p))) + FIT |
Figure . Top: crystal energy landscape of Desloratadine from CrystalOptimizer. Bottom left: crystal energy landscape of Desloratadine with PCM correction to rigid molecule structure of CrystalOptimizer structures. Bottom right: relative energies with different methods.
Table . Crystallographic information for CSD entries for Desloratadine. Different polymorphs are coloured differently.
| REFCODE | space group | Z’ | a / Å | b / Å | c / Å | α / ° | β / ° | γ / ° | density / g cm-3 | Form |
|---|---|---|---|---|---|---|---|---|---|---|
| GEHXEX | P21 | 1 | 6.9336 | 11.998 | 9.4691 | 90 | 107.365 | 90 | 1.373 | I |
| GEHXEX01 | P21 | 1 | 6.9522 | 12.006 | 9.4804 | 90 | 107.387 | 90 | 1.367 | I |
| GEHXEX02 | P21 | 1 | 7.7534 | 12.1384 | 9.608 | 90 | 118.78 | 90 | 1.302 | III |
| GEHXEX03 | P21 | 1 | 7.061 | 12.0699 | 9.559 | 90 | 108.2 | 90 | 1.334 | I |
| GEHXEX04 | P21 | 2 | 14.818 | 12.223 | 9.631 | 90 | 113.255 | 90 | 1.288 | II |
Table . Experimental information for CSD entries for Desloratadine.
| REFCODE | space group | R factor | T / K | Year | Comments |
|---|---|---|---|---|---|
| GEHXEX | P21 | 3.2 | 100 | 2006 | Slow evaporation from ethyl acetate1 |
| GEHXEX01 | P21 | 4.21 | 80 | 2020 | Slow evaporation from ethyl acetate2 |
| GEHXEX02 | P21 | 3.99 | 360 | 2020 | Heating in DSC or VT-PXRD2 |
| GEHXEX03 | P21 | 4.79 | 293 | 2020 | End point of a heating/cooling cycle?2 |
| GEHXEX04 | P21 | 6.57 | 335 | 2020 | Heating in DSC or VT-PXRD2 |
On heating desloratadine, either as a single crystal, as a powder, in the DSC or in VT-Raman, two phase transformations occur. All the forms are enantiotropically related, and Forms I and III differ in the orientation of the 6-membered ring with respect to the benzodiazepine group. In Form II, half the molecules take each conformation (it is not disordered).
1. P. M. Bhatt and G. R. Desiraju, Acta Crystallographica Section C, 2006, 62, o362-o363.
2. V. K. Srirambhatla, R. Guo, D. M. Dawson, S. L. Price and A. J. Florence, Crystal Growth & Design, 2020, 20, 1800-1810.