The design of pharmaceutical cocrystals has initiated widespread debate on the classification of cocrystals. Current attempts to classify multicomponent crystals suffer from ambiguity, which has led to inconsistent definitions for cocrystals and for multicomponent crystals in general. Inspired by the work of Aitipamula et al. (Cryst. Growth Des. 2012, 12, 2147–2152), we present a feasible classification system for all multicomponent crystals. The present classification enables us to analyze and classify multicomponent crystal structures present in the Cambridge Structural Database (CSD). This reveals that all seven classes proposed are relevant in terms of frequency of occurrence. Lists of CSD refcodes for all classes are provided. We identified over 5000 cocrystals in the CSD, as well as over 12 000 crystals with more than two components. This illustrates that the possibilities for alternative drug formulations can be increased significantly by considering more than two components in drug design.

The formation of conglomerate salts from chiral molecules, which crystallize as racemic compounds, expands the theoretical application range of Viedma Ripening roughly 10 fold. In the present study, on the use of conglomerate forming salts was studied for temperature cycling, an alternative technique for Viedma ripening. The racemic compound Phenyalanine (Phe) was successfully deracemized via its conglomerate-forming salt with 2,5-xylenesulfonic acid (XSA) by continuous heating-cooling cycles applied to its suspension in glacial acetic acid, coupled with a solution racemization reaction. In addition, the dependence of the deracemization rate on the operational parameters was studies. The results can be used as guidelines for process optimization as well as for the understanding of the mechanism behind temperature cycling. The advantages and disadvantages of temperature cycling and Viedma Ripening, as deracemization methods in an industrial setting are discussed.

Since the first distribution of Molden in 1995 and the publication of the first article about this software in 2000 work on Molden has continued relentlessly. A few of the many improved or fully novel features such as improved and broadened support for quantum chemistry calculations, preparation of ligands for use in drug design related softwares, and working with proteins for the purpose of ligand docking.

As ignificant amount of attention has been given to the design and synthesis of co-crystals by both industry and academia because of its potential to change am olecules physicochemical properties.Y et, difficulties arise when searching for adequate combinations of molecules (or coformers) to form co-crystals,h ampering the efficient exploration of the targetss olid-state landscape.T his paper reports on the application of ad ata-driven co-crystal prediction method based on two types of artificial neural network models and cocrystal data present in the Cambridge Structural Database.The models accept pairs of coformers and predict whether ac ocrystal is likely to form. By combining the output of multiple models of both types,o ur approach shows to have excellent performance on the proposed co-crystal training and validation sets,and has an estimated accuracy of 80 %for molecules for which previous co-crystallization data is unavailable.

Aligned unidirectional collagen scaffolds may aid regeneration of those tissues where alignment of cells and extracellular matrix is essential, as for instance in cartilage, nerve bundles, and skeletal muscle. Pores can be introduced by ice crystal formation followed by freeze-drying, the pore architecture reflecting the ice crystal morphology. In this study we developed a wedge-based system allowing the production of a wide range of collagen scaffolds with unidirectional pores by directional freezing. Insoluble type I collagen suspensions were frozen using a custom-made wedge system, facilitating the formation of a horizontal as well as a vertical temperature gradient and providing a controlled solidification area for ice dendrites. The system permitted the growth of aligned unidirectional ice crystals over a large distance (>2.5 cm), an insulator prolonging the freezing process and facilitating the construction of crack-free scaffolds. Unidirectional collagen scaffolds with tunable pore sizes and pore morphologies were constructed by varying freezing rates and suspension media. The versatility of the system was indicated by the construction of unidirectional scaffolds from albumin, poly(vinyl alcohol) (a synthetic polymer), and collagen-polymer blends producing hybrid scaffolds. Macroscopic observations, temperature measurements, and scanning electron microscopy indicated that directed horizontal ice dendrite formation, vertical ice crystal nucleation, and evolutionary selection were the basis of the aligned unidirectional ice crystal growth and, hence, the aligned unidirectional pore structure. In conclusion, a simple, highly adjustable freezing system has been developed allowing the construction of large (hybrid) bioscaffolds with tunable unidirectional pore architecture.

Viedma ripening proceeds through an autocatalytic feedback mechanism which exponentially deracemizes an initially racemic solid state to an enantiopure end state. Here we show that, in the presence of enantiopure additives with a concentration of as low as 2.5 × 10 −2 mol %, Viedma ripening proceeds with an overall linear and faster increase in enantiomeric excess. These experimental results can be explained using a simple model which assumes a difference in growth and dissolution rates between the enantiomers. This model also accounts for the generally observed linearity during the initial stages of Viedma ripening without additives.

The crystalline sponge method entails the elucidation of the (absolute) structure of molecules from a solution phase using single‐crystal X‐ray diffraction and eliminates the need for crystals of the target compound. An important limitation for the application of the crystalline sponge method is the instability of the available crystalline sponges that can act as host crystals. The host crystal that is most often used decomposes in protic or nucleophilic solvents, or when guest molecules with Lewis basic substituents are introduced. Here a new class of (water) stable host crystals based on f‐block metals is disclosed. It can be shown that these hosts not only increase the scope of the crystalline sponge method to a wider array of solvents and guests, but that they can even be applied to aqueous solutions containing hydrophilic guest molecules, thereby extending the crystalline sponge method to the important field of water‐based chemistry.

Mefloquine is an important drug for prevention and treatment of malaria. It is commercially available as a racemic mixture, wherein only one enantiomer is active against malaria, while the other one causes severe psychotropic effects. By converting the drug into a compound that crystallizes as a racemizable racemic conglomerate, the deracemization of mefloquine into the desired enantiomer was achieved.