Themed collection The Solid State of Pharmaceuticals
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The solid state of pharmaceuticals
Welcome to this CrystEngComm themed issue entitled “The solid state of pharmaceuticals.”
CrystEngComm, 2019,21, 2031-2033
https://doi.org/10.1039/C9CE90044F
Polymorphism in p-aminobenzoic acid
We review the polymorphism of p-aminobenzoic acid (pABA), a model drug compound whose crystallisation and polymorphic behaviour has been extensively studied in recent years.
CrystEngComm, 2019,21, 2034-2042
https://doi.org/10.1039/C8CE01890A
Determining short-lived solid forms during phase transformations using molecular dynamics
We demonstrate that elusive high-energy metastable crystal structures can be determined from molecular dynamics simulations.
CrystEngComm, 2019,21, 4020-4024
https://doi.org/10.1039/C9CE00460B
Capturing a new hydrate polymorph of amodiaquine dihydrochloride dihydrate via heterogeneous crystallisation
A new polymorph of amodiaquine dihydrochloride dihydrate was obtained via heterogenous crystallization. This new polymorph showed difference in two-dimensional sheet structure compare to previously known polymorph.
CrystEngComm, 2019,21, 2053-2057
https://doi.org/10.1039/C8CE01720D
Role of hydrogen bonding in cocrystals and coamorphous solids: indapamide as a case study
Crystalline and amorphous stable binary compounds of indapamide for high solubility and permeability.
CrystEngComm, 2019,21, 2043-2048
https://doi.org/10.1039/C8CE01075G
Remarkable decrease in stiffness of aspirin crystals upon reducing crystal size to nanoscale dimensions via sonochemistry
Nano-dimensional crystals of aspirin generated through sonochemistry exhibit Young's modulus values an order of magnitude softer than macro-dimensional crystals.
CrystEngComm, 2019,21, 2049-2052
https://doi.org/10.1039/C8CE00764K
Mechanochemistry vs. solution growth: striking differences in bench stability of a cimetidine salt based on a synthetic method
A mechanochemically prepared solvated salt of an archetypal blockbuster drug exhibits significantly different bench stability to analogous material made in solution.
CrystEngComm, 2018,20, 7242-7247
https://doi.org/10.1039/C8CE01727A
Profoundly improved photostability of dimetronidazole by cocrystallization
Cocrystallization with saccharine (SAC) significantly improved photostability of dimetronidazole (DMZ), an veterinary antibiotic.
CrystEngComm, 2022,24, 6165-6171
https://doi.org/10.1039/D2CE00597B
Pharmaceutical paroxetine-based organic salts of carboxylic acids with optimized properties: the identification and characterization of potential novel API solid forms
Reacting paroxetine HCl with oxalic, maleic, fumaric and L-tartaric acids results in the formation of novel molecular salts.
CrystEngComm, 2019,21, 3668-3678
https://doi.org/10.1039/C8CE02076K
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Conundrum of γ glycine nucleation revisited: to stir or not to stir?
Stirring promotes formation of the metastable α glycine polymorph, whereas stable γ glycine forms under quiescent conditions.
CrystEngComm, 2019,21, 2234-2243
https://doi.org/10.1039/C8CE01829D
Tautomer selection through solvate formation: the case of 5-hydroxynicotinic acid
Different 5-hydroxynicotinic acid tautomers were selectively captured through solvate formation. The selectivity is lost once the memory of solvation is erased by removing the solvent from the crystal lattice.
CrystEngComm, 2019,21, 2220-2233
https://doi.org/10.1039/C8CE02108B
![Open Access](https://www.rsc-cdn.org/pubs-core/2022.0.148/content/NewImages/open-access-icon-orange.png)
Crystallisation in printed droplets: understanding crystallisation of D-mannitol polymorphs
Crystallising D-mannitol in printed droplets provides new insights into understanding the effect of foreign surfaces on the formation of its polymorphs.
CrystEngComm, 2019,21, 2212-2219
https://doi.org/10.1039/C8CE01780H
On the prevalence of smooth polymorphs at the nanoscale: implications for pharmaceuticals
Ball mill neat grinding leads to smoother whereas liquid assisted grinding leads to rougher pharmaceutical forms.
CrystEngComm, 2019,21, 2203-2211
https://doi.org/10.1039/C8CE02098A
Discovery and recovery of delta p-aminobenzoic acid
A new high-pressure recoverable form has been observed in the model system, p-aminobenzoic acid.
CrystEngComm, 2019,21, 2058-2066
https://doi.org/10.1039/C8CE01882K
![Open Access](https://www.rsc-cdn.org/pubs-core/2022.0.148/content/NewImages/open-access-icon-orange.png)
Ball size or ball mass – what matters in organic mechanochemical synthesis?
The effects of milling ball mass, size and material are isolated for a model mechanochemical co-crystallisation.
CrystEngComm, 2019,21, 2174-2179
https://doi.org/10.1039/C8CE02109K
Solvent driven phase transitions of acyclovir – the role of water and solvent polarity
The pathways of transformations of acyclovir forms I and V induced by organic solvents and water have been identified. Significant differences in the thermal dehydration process of forms V and VI were observed.
CrystEngComm, 2019,21, 2180-2192
https://doi.org/10.1039/C8CE01814F
The use of biocompatible crystalline substrates for the heterogeneous nucleation and polymorphic selection of indomethacin
A heteroepitaxial nucleation approach was used to control the phase selective nucleation of indomethacin using biocompatible, organic crystalline substrates.
CrystEngComm, 2019,21, 2193-2202
https://doi.org/10.1039/C8CE01517A
Solvent-polymer guest exchange in a carbamazepine inclusion complex: structure, kinetics and implication for guest selection
Solvent–polymer guest exchange in a carbamazepine inclusion complex in a stirred solution was studied and a mechanism was proposed.
CrystEngComm, 2019,21, 2164-2173
https://doi.org/10.1039/C8CE01766B
![Open Access](https://www.rsc-cdn.org/pubs-core/2022.0.148/content/NewImages/open-access-icon-orange.png)
The solid state forms of the sex hormone 17-β-estradiol
The crystal structure of the female sex hormone has been established despite its high affinity for water.
CrystEngComm, 2019,21, 2154-2163
https://doi.org/10.1039/C8CE01874J
Stanozolol–aromatic carboxylic acid crystalline complexes: flexible tautomeric/ionization states and supramolecular synthons
The various supramolecular synthons are constantly spinning in the crystal world.
CrystEngComm, 2019,21, 2144-2153
https://doi.org/10.1039/C8CE01439F
Accuracy and reproducibility in crystal structure prediction: the curious case of ROY
Because of excessive electron delocalization, the polymorphs of ROY constitute a surprisingly challenging system for crystal structure prediction.
CrystEngComm, 2019,21, 2080-2088
https://doi.org/10.1039/C8CE01902A
High thermal stability, pH responsive organogels of 2H-benzo[d]1,2,3-triazole derivatives as pharmaceutical crystallization media
2H-Benzo[d]1,2,3-triazole derivatives give rise to a supergelator that results in the crystallization of kinetic form I sulfathiazole.
CrystEngComm, 2019,21, 2135-2143
https://doi.org/10.1039/C8CE01742E
Explaining crystallization preferences of two polyphenolic diastereoisomers by crystal structure prediction
Crystal structure prediction is used to understand the differences in crystallization of catechin and epicatechin, and to explore the predictability of solvate formation.
CrystEngComm, 2019,21, 2067-2079
https://doi.org/10.1039/C8CE01783B
Design of 4-aminobenzoic acid two-component molecular crystals: prediction and experiments
Cocrystal formation of 4-aminobenzoic acid with a variety of pyrimidine, pyridine and benzamide derivatives has been investigated.
CrystEngComm, 2019,21, 2119-2129
https://doi.org/10.1039/C8CE01857J
Co-crystallization and polymorphic behaviour of 5-fluorouracil
Hydrogen donors and acceptors in 5-fluorouracil allow the formation of co-crystalline compounds with nontoxic co-formers of the GRAS list and an alternative target-oriented synthon approach from methanol or ethanol to form II of 5-fluorouracil is presented.
CrystEngComm, 2019,21, 2130-2134
https://doi.org/10.1039/C8CE01692E
![Open Access](https://www.rsc-cdn.org/pubs-core/2022.0.148/content/NewImages/open-access-icon-orange.png)
Polymorph control in batch seeded crystallizers. A case study with paracetamol
We show that seeding is not always sufficient to control cystal polymorphism and illustrate how kinetic modeling can help controlling polymorphism.
CrystEngComm, 2019,21, 2105-2118
https://doi.org/10.1039/C8CE01428K
Robust bulk preparation and characterization of sulfamethazine and saccharine salt and cocrystal polymorphs
The complex between sulfamethazine and saccharine (SMT–SAC) can exist in two polymorphs, one is a cocrystal and the other is a salt.
CrystEngComm, 2019,21, 2089-2096
https://doi.org/10.1039/C8CE01076E
On the kinetics of solvate formation through mechanochemistry
We demonstrate that solvates obtained through mechanochemistry are the thermodynamic products, and that the kinetics of solvate formation are related to the easiness of breaking the reactant crystals.
CrystEngComm, 2019,21, 2097-2104
https://doi.org/10.1039/C8CE00871J
About this collection
This themed collection focuses on the experimental and computational investigation of crystal polymorphism, solvate and hydrate formation of pharmaceutical compounds. Topics range from the study of nucleation and crystallisation to the discovery, computational prediction and design of new solid forms of drug compounds.