Describing hydrogen-bonded structures; topology graphs, nodal symbols and connectivity tables, exemplified by five polymorphs of each of sulfathiazole and sulfapyridine
نویسندگان
چکیده
BACKGROUND Structural systematics is the comparison of sets of chemically related crystal structures with the aim to establish and describe relevant similarities and relationships. An important topic in this context is the comparison of hydrogen-bonded structures (HBSs) and their representation by suitable descriptors. RESULTS Three different description methods for HBSs are proposed, a graphical representation, a symbolic representation and connectivity tables. The most comprehensive description is provided by a modified graph of the underlying net topology of an HBS which contains information on the multiplicity of links, the directionality and chemical connectivity of hydrogen bonds and on symmetry relations. By contrast, the alternative symbolic representation is restricted to essential properties of an HBS, i.e. its dimensionality, topology type and selected connectivity characteristics of nodes. A comparison of their connectivity tables readily identifies differences and similarities between crystal structures with respect to the intermolecular interaction modes adopted by their functional groups. The application of these methods to the known polymorphs of sulfathiazole and sulfapyridine is demonstrated and it is shown that they enable the rationalisation of previously reported and intricate relationships. CONCLUSIONS The proposed methods facilitate the comprehensive description of the most important relevant aspects of an HBS, including its chemical connectivity, net topology and symmetry characteristics, and they represent a new way to recognise similarities and relationships in organic crystal structures. Graphical AbstractGraphical Representation of mixing of structures StzIV and StzV to give structure StzIII.
منابع مشابه
Isogeometric Topology Optimization of Continuum Structures using an Evolutionary Algorithm
Topology optimization has been an interesting area of research in recent years. The main focus of this paper is to use an evolutionary swarm intelligence algorithm to perform Isogeometric Topology optimization of continuum structures. A two-dimensional plate is analyzed statically and the nodal displacements are calculated. The nodal displacements using Isogeometric analysis are found to be ...
متن کاملThe Therapy of Acute Staphylococcal Infection of Mice with Antitoxin and Sulfonamide Compounds *
Long and Bliss,20 and Mellon, Gross, and Cooper,24 in their monographs, have reviewed the conflicting evidence on the action of sulfanilamide, neoprontosil, and other early derivatives which have not found satisfactory clinical application. The reported experimental work on the action of sulfapyridine, sulfathiazole, and sulfamethylthiazole has held out greater promise of success against the st...
متن کاملPolymorphs of layered assemblies of hydrogen-bonded hexagonal networks caused by conformational frustration.
Generation of four polymorphs of 2D-nCOF crystals that are formed through stacking of a hydrogen-bonded, hexagonally-networked framework is revealed for the first time. The structural diversity is caused not from the topology or the stacking manner of the framework but from subtle structural factors such as rotational conformation and location of conformational frustration within the framework.
متن کاملObservations on the Absorption, Excretion, Diffusion, and Acetylation of Sulfathiazole in Man *
The sulfonamide derivatives differ from compound to compound not only in scope and effectiveness of chemotherapeutic action4 but also in their pharmacological properties."8 It becomes important, therefore, with each new compound introduced, after preliminary studies in animals, to determine the facts concerning these properties in man. In this paper are recorded observations in man on the absor...
متن کاملRhombellanic Crystals and Quasicrystals
Design of some crystal and quasicrystal networks, based on rhombellane tiling,is presented. [1,1,1]Propellane,is a synthesized organic molecule; its hydrogenated form, the bicyclo[1.1.1]pentane,may be represented by the complete bipartite graph K2,3 which is the smallest rhombellane. Topology of translational and radial structures involving rhombellanes is described in terms of vertex symbol, c...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 9 شماره
صفحات -
تاریخ انتشار 2015