Racemic mimics. Part 1. Nickel coordination com­pounds

There are very few examples of crystallographically well-documented racemic mimics. Therefore, this inter­esting class of crystalline mol­ecules, potentially having useful biological uses, is today one of those scientific orphans largely ignored in the crystallographic realm. Some suggestions are provided for searching for potential cases of such a crystallization mode using information already in print.

Single-crystal structure of the spicy capsaicin

The crystal structure of capsaicin, the natural product responsible for the pungency of chilli peppers, was determined by low-temperature single-crystal X-ray diffraction.

Mixed cocrystal approach influences the yield for a [2+2] cyclo­addition reaction within a halogen-bonded organic solid

The ability to control the yield for a [2+2] cyclo­addition photoreaction by using a mixed cocrystal approach is reported. The two isosteric halogen-bond donors allow for the formation of the cocrystal solid solution and as a result influences the extent of the photoreaction based upon their initial molar ratios.

7-(4-Chloro­phen­yl)-1-hy­droxy-5-methyl­pyrido[3,4-d]pyridazin-4(3H)-one: synthesis, solvatomorphism, in vitro anti-inflammatory and cytotoxic activity studies and in silico analysis

The biological activity of a newly synthesized py­rido[3,4-d]pyridazinone was investigated in terms of cytotoxic (on the normal cell lines L929 and RPTEC, as well as the cancer cell lines A172, AGS, CACO-2 and HepG2) and anti-inflammatory (using colorimetric assay for inhibition of COX-1 and COX-2) properties.

Structural and supra­molecular insights into crystalline multicom­ponent systems of 2,4-di­amino-6-phenyl-1,3,5-tri­azine with various carb­oxy­lic acids

The supra­molecular inter­actions and Hirshfeld surfaces of three multicom­ponent systems, namely, 2,4-di­amino-6-phenyl-1,3,5-tri­a­z­ine–nicotinic acid, 2,4-di­amino-6-phenyl-1,3,5-triazin-1-ium hy­dro­gen malonate and 2,4-di­amino-6-phenyl-1,3,5-triazin-1-ium hy­dro­gen (+)-dibenzoyl-D-tartarate have been investigated.

Halogen-substituted benzyl­amine crown ether inclusion com­plexes

Four novel benzyl­amine-based crown ether inclusion com­plexes have been synthesized, [(4-XBA)(18-crown-6)][DMSA] [X = F, Cl, Br and I; BA= benzyl­amine; DMSA = di(methane­sulfony)amidate]. The effects of the different halogen atoms on the stacking within the crystals of the com­plexes are described.

8-Ethynyl-2′-de­oxy­iso­guano­sine with two tautomeric forms in the unit cell: crystal structure, packing and Hirshfeld surface analysis

8-Ethynyl-2′-de­oxy­iso­guano­sine exists as an organized mixture of the N1-H and N3-H tautomers in the solid state. The nu­cle­o­side is in a syn conformation, which is stabilized by hy­dro­gen bonds between the heterocycle and the sugar residue. A tridentate purine–purine base pair in the crystal packing is enabled by alteration of the donor–acceptor pattern of the nucleo­base due to tautomerism.

Transformations of thio­carbonyls into alkenes via Barton–Kellogg olefination

The Barton–Kellogg olefination of a thio­benzo­phenone and a 3H-1,2-di­thiole-3-thione yields the corresponding alkenes, whose solid-state structures, along with that of an inter­mediate thiirane, have been characterized and found to be similar to those of related com­pounds.

KHfF₅: a new representative in the M^IM^IVF₅ family

A com­parison of the structure of newly synthesized KHfF₅ with other com­plex fluorides of alkali metals and hafnium, zirconium or terbium(IV) revealed that this com­pound has no isostructural analogue among the known phases of general com­position M^IM^IVF_5.