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Nα-2-thiophenoyl-d-phenylalanine-2-morpholinoanilide [MMV688845, Pathogen Box; Medicines for Malaria Venture; IUPAC: (2R)-N-(1-((2-morpholinophenyl)amino)-1-oxo-3-phenylpropan-2-yl)thiophene-2-carboxamide)] is a hit compound, which shows activity against Mycobacterium abscessus(MIC906.25–12.5 μM) and other mycobacteria. This work describes derivatization of MMV688845 by introducing a thiomorpholine moiety and the preparation of the corresponding sulfones and sulfoxides. The molecular structures of three analogs are confirmed by X-ray crystallography. Conservation of the essential Rconfiguration during synthesis is proven by chiral HPLC for an exemplary compound. All analogs were characterized in a MIC assay against M. abscessus, Mycobacterium intracellulare, Mycobacterium smegmatis, and Mycobacterium tuberculosis. The sulfone derivatives exhibit lower MIC90values (M. abscessus: 0.78 μM), and the sulfoxides show higher aqueous solubility than the hit compound. The most potent derivatives possess bactericidal activity (99% inactivation of M. abscessusat 12.5 μM), while they are not cytotoxic against mammalian cell lines.

The crystal structure of [Co(NH3)6](ADC)(HADC) · 2H2O (1) (ADC2-=acetylenedicarboxylate) (P21=n, Z = 4) was mistakenly described as containing the [Co(H2O)6]3+ion [I. Stein, U. Ruschewitz, Z. Naturforsch. , 66b, 471 - 478]. A revision is reported. While attempting to reproduce 1, we isolated phase-pure crystalline material of [Co(NH3)6]Cl2(HADC) · H2O (2), the crystal structure of which was also reported in the article above. Upon standing in the aqueous mother liquor at room temperature for several days, the needle-shaped crystals of 2disappear, while blockshaped crystals of the formerly unknown compound [Co(NH3)6](ADC)(HADC) (3) grow. Satellite peaks in the X-ray diffraction frames indicate that the crystal structure is incommensurately modulated. Dissolving crystals of 3 in water at elevated temperature leads to plate-shaped crystals of the new compound [Co(NH3)6]2(ADC)3· 3H2O (4) upon slow cooling to room temperature. Compounds 2- 4 were investigated by elemental analysis, powder X-ray diffraction and infrared spectroscopy. Structural characterization of 4 by single-crystal X-ray analysis was also achieved (P1̅ , Z = 2). Complex 1, however, could not be reproduced

The synthesis, characterization, and theoretical investigation by means of quantum‐chemical calculations of an oligonuclear metal‐rich compound are presented. The reaction of homoleptic dinuclear palladium compound [Pd2(μ‐GaCp*)3(GaCp*)2] with ZnMe2resulted in the formation of unprecedented ternary Pd/Ga/Zn compound [Pd2Zn6Ga2(Cp*)5(CH3)3] (1), which was analyzed by 1H and 13C NMR spectroscopy, MS, elemental analysis, and single‐crystal X‐ray diffraction. Compound 1consisted of two Cs‐symmetric molecular isomers, as revealed by NMR spectroscopy, at which distinct site‐preferences related to the Ga and Zn positions were observed by quantum‐chemical calculations. Structural characterization of compound 1showed significantly different coordination environments for both palladium centers. Whilst one Pd atom sat in the central of a bi‐capped trigonal prism, thereby resulting in a formal 18‐valence electron fragment, {Pd(ZnMe)2(ZnCp*)4(GaMe)}, the other Pd atom occupied one capping unit, thereby resulting in a highly unsaturated 12‐valence electron fragment, {Pd(GaCp*)}. The bonding situation, as determined by atoms‐in‐molecules analysis (AIM), NBO partial charges, and molecular orbital (MO) analysis, pointed out that significant PdPd interactions had a large stake in the stabilization of this unusual molecule. The characterization and quantum‐chemical calculations of compound 1revealed distinct similarities to related M/Zn/Ga Hume–Rothery intermetallic solid‐state compounds, such as Ga/Zn‐exchange reactions, the site‐preferences of the Zn/Ga positions, and direct MM bonding, which contributes to the overall stability of the metal‐rich compound.

A series of mixed‐metal layer‐pillared MOFs of general formula [Zn1–xCux(bdc)(dabco)0.5] (bdc = 1,4‐benzenedicarboxylate, dabco = 1,4‐diazabicyclo[2.2.2]octane, 0 < x< 1) have been synthesized by a solvothermal approach. Different amounts xof Cu2+were introduced to substitute for Zn2+centers. The prepared mixed‐metal MOFs were shown to be structurally very similar to their parent monometallic [Zn(bdc)(dabco)0.5] and [Cu(bdc)(dabco)0.5] frameworks by single‐crystal and powder X‐ray diffraction studies. Interestingly, upon inclusion of copper, a distortion of the paddle‐wheel units is observed. In addition, the incorporation of Cu2+ions into the [Zn2(bdc)(dabco)0.5] framework and the formation of heterometallic Zn–Cu paddle‐wheel units along with monometallic Cu–Cu and Zn–Zn units in the prepared mixed‐metal MOFs were confirmed by continuous‐wave EPR spectroscopy. The synthesized materials [Zn1–xCux(bdc)(dabco)0.5] are thermally stable up to 260 °C and exhibit permanent porosity with BET surface areas in the range of 800–2430 m2g–1.

Attempts to crystal engineermetallosupramolecularcomplexes from Cu(phen)2+building blocks and the prototypical,rod‐like, exo‐bidentate ligand 4,4′‐bipyridine (4,4′‐bipy) by layering techniques are described. Reactions of Cu(phen)2+(phen = 1,10‐phenanthroline) with 4,4′‐bipy in the presence of NO3–counterions yielded two distinct, discrete, dinuclear, Cisymmetric, dumbbell‐typecomplexes, [{Cu(NO3)2(phen)}2(4,4′‐bipy)] (1) and [{Cu(NO3)(phen)(H2O)}2(4,4′‐bipy)](NO3)2(2), depending upon the mixture of solvents used for crystallization. In compound 1, a mono‐ and a bidentate nitrato group coordinate to Cu2+, whereas in 2the monodentate nitrato groups are replaced by aqua ligands, which introduce additional hydrogen‐bond donor functionality to the molecule. The crystal structure of 1was determined by single‐crystal X‐ray analysis at 296 and 110 K. Upon cooling, a disorder‐order transition occurs, with retention of the space group symmetry. The crystal structure of 2at room temperature was reported previously [Z.‐X. Du, J.‐X. Li, Acta Cryst. 2007, E63, m2282]. We have redetermined the crystal structure of 2at 100 K. A phase transition is not observed for 2, but the low temperature single‐crystal structure determination is of significantly higher precision than the room temperature study. Both 1and 2are obtained phase‐pure, as proven by powder X‐ray diffraction of the bulk materials. Crystals of [Cu(phen)(CF3SO3)2(4,4′‐bipy)·0.5H2O]n(3), a one‐dimensional coordination polymer, were obtained from [Cu(CF3SO3)2(phen)(H2O)2] and 4,4′‐bipy. In 3, Cu(phen)2+corner units are joined by 4,4′‐bipy via the two vacant cissites to form polymeric zig‐zag chains, which are tightly packed in the crystal. Compounds 1–3were further studied by infrared spectroscopy.

Inseparable zinc pair: The reaction of homoleptic {GaCp*}‐containing compounds [M(GaCp*)4] (M=Pd, Pt; Cp*=Me5C5) with [Zn2Cp*2] leads to the formation of [M(GaCp*)2(ZnCp*)2(ZnZnCp*)2] (see picture: C gray, Ga yellow, Zn green, Pd blue) and [M(ZnCp*)4(ZnZnCp*)4]. Both molecules involve the novel zinc ligand system {ZnZnCp*}, which contains an intact ZnZn bond.

Unzertrennliches Zinkpärchen: Die Reaktion von homoleptischen {GaCp*}‐Verbindungen [M(GaCp*)4] (M=Pd, Pt; Cp*=Pentamethylcyclopentadienyl) mit [Zn2Cp*2] führt zur Bildung von [M(GaCp*)2(ZnCp*)2(ZnZnCp*)2] (siehe Bild; grau C, gelb Ga, grün Zn, blau Pd) und [M(ZnCp*)4(ZnZnCp*)4]. Beide Moleküle enthalten den neuartigen Liganden {ZnZnCp*} mit einer intakten Zn‐Zn‐Bindung.

Self‐assembly of Cd(phen)2+and Cu(phen)2+(phen = 1,10‐phenanthroline) building blocks with the bent ligand 4,4′‐dithiodipyridine (dtdp) has been investigated. Both building blocks serve as corner units with constrained cis‐geometry. The arched chain coordination polymer [{Cd(phen)(μ‐dtdp)(dtdp)(H2O)}(ClO4)2·2CH3OH·1.5H2O]n(1) crystallised from a mixture of Cd(ClO4)2·H2O, phen and dtdp in methanol. The reaction of [Cu(phen)(H2O)2](CF3SO3)2(2) with dtdp in an ethanol/water mixture yielded a chair‐like metallamacrocycle, [{Cu(phen)(CF3SO3)2}2(μ‐dtpd)2] (3). The crystal structure of the precursor complex 2is also reported.

The synthesis and structural characterisation of low‐valent dinuclear copper(I) and copper(0) complexes supported by organogallium ligands has been accomplished for the first time by the reductive coordination reaction of [GaCp*] (Cp*=pentamethylcyclopentadienyl) and [Ga(ddp)] (ddp=HC(CMeNC6H3‐2,6‐iPr2)22‐diisopropylphenylamino‐4‐diisopropylphenylimino‐2‐pentene) with readily available copper(II) and copper(I) precursors. The treatment of CuBr2and Cu(OTf)2(OTf=CF3SO3) with [Ga(ddp)] under mild conditions resulted in elimination of [Ga(L)2(ddp)] (L=Br, OTf) and afforded the novel gallium(I)/copper(I) compounds [{(ddp)GaCu(L)}2] (L=Br (1), OTf (2)). The single‐crystal X‐ray structure determinations of 1and 2reveal that these molecules are composed of {(ddp)GaCu(L)} dimeric units, with planar CuIGaIfour‐membered rings and short CuI⋅⋅⋅CuIdistances, with 2exhibiting the shortest CuI⋅⋅⋅CuIcontact reported to date of 2.277(3) Å. The all‐gallium coordinated dinuclear [Cu2(GaCp*)(μ‐GaCp*)3Ga(OTf)3] (3) is formed when Cu(OTf)2is combined with [GaCp*] instead of [Ga(ddp)]. Notably, in the course of this redox reaction Lewis acidic Ga(OTf)3is formed, which coordinates to one of the electron‐rich copper(0) centres. Compound 3is suggested as the first case of a structurally characterised complex of copper(0). By changing the copper(II) to a copper(I) source, that is, [Cu(cod)2][OTf] (cod=1,5‐cyclooctadiene), the salt [Cu2(GaCp*)3(μ‐GaCp*)2][OTf]2(4) is formed, the cationic part of which is related to previously described isoelectronic dinuclear d10complexes of the type [M2(GaCp*)5] (M=Pd, Pt).

The 2:1 sandwich‐type complexes formed between a cyclopeptide with alternating L‐proline and 6‐aminopicolinic acid subunits and inorganic anions can be stabilized by covalently linking a tris‐alkyne and a tris‐azide derivative of this peptide through copper‐catalyzed azide–alkyne cycloaddition. The resulting triply linked bis‐cyclopeptide can interact with anions such as sulfate ions in aqueous solution by including them into the cavity between the two cyclopeptide rings, where they can form hydrogen bonds to amide NH groups, distributed along the inner surface. The binding kinetics of this system differ significantly from those of a bis‐cyclopeptide that contains only one linker because the rate of guest exchange is considerably slower. Thermodynamically, the stability of the sulfate complex of the triply linked bis‐cyclopeptide approaches a log Kavalue of 6 in H2O/CH3OH 1:1 (v/v) which is, however, only approximately one order of magnitude larger than affinity of the more flexible monolinked analogue. Titration calorimetry revealed that this behavior is mainly due to the change in the binding enthalpy from exothermic to endothermic upon increasing the number of linkers. Results from NMR spectroscopy and X‐ray crystallography indicate that the mono‐ and triply linked bis‐cyclopeptides adopt similar conformations in their complexes with sulfate ions, but the complex formation is enthalpically unfavorable for the cage. The substantial entropic contribution to sulfate complexation of this receptor more than compensates for this disadvantage, so that the overall sulfate affinity of both bis‐cyclopeptides ends up in the same range. These investigations provide important insight into the structure–property relationships of such receptors, thus leading the way to further structural improvement.

Heavy‐metal complexes of lead and mercury stabilized by Group 13 ligands were derived from the oxidative addition of Ga(ddp) (ddp=HC(CMeNC6H3‐2,6‐iPr2)2, 2‐diisopropylphenylamino‐4‐diisopropyl phenylimino‐2‐pentene) with corresponding metal precursors. The reaction of Me3PbCl and Ga(ddp) afforded compound [{(ddp)Ga(Cl)}PbMe3] (1) composed of GaPbIVbonds. In addition, the monomeric plumbylene‐type compound [{(ddp)Ga(OSO2CF3)}2Pb(thf)] (2 a) with an unsupported Ga‐PbII‐Ga linkage was obtained by the reaction of [Pb(OSO2CF3)3] with Ga(ddp) (2 equiv). Compound 2 afalls under the rare example of a discrete plumbylene‐type compound supported by a nonclassical ligand. Interesting structural changes were observed when [Pb(OSO2CF3)3]⋅2 H2O was treated with Ga(ddp) in a 1:2 ratio to yield [{(ddp)Ga(μ‐OSO2CF3)}2(OH2)Pb] (2 b) at below −10 °C. Compound 2 bconsists of a bent Ga‐Pb‐Ga backbone with a bridging triflate group between the GaPb bond and a weakly interacting water molecule at the gallium center. Similarly, the reaction of mercury thiolate Hg(SC6F5) with Ga(ddp) (2 equiv) produced the bimetallic homoleptic compounds anti‐[{(ddp)Ga(SC6F5)}2Hg] (3 a) and gauche‐[{(ddp)Ga(SC6F5)}2Hg] (3 b), respectively, with a linear Ga‐Hg‐Ga linkage. Compounds 1–3were structurally characterized and these are the first examples of compounds comprised of GaPbII, GaPbIV, and GaHg bonds.

A structural study on two isotypic infinite 2D metallosupramolecular arrays of Zinc‐5,10,15,20‐tetra(4‐pyridyl)porphyrin (ZnTPyP) has been undertaken. [ZnX2(μ3‐ZnTPyP)·3TCE]n(X= Cl, Br; TCE = 1,1,2,2‐tetrachloroethane) form extended 2D grid structures driven by self‐complementary axial coordination of the metalloporphyrin entities. They both crystallize in the monoclinic system, P21/c, Z= 4, a= 19.1176(15), b= 12.931(1), c= 21.8124(18) Å, β= 103.306(8)°, V= 5247.6(7) Å3for X= Cl and a= 19.1644(7), b= 12.9984(5), c= 21.9013(9) Å, β= 103.141(4)°, V= 5312.9(4) Å3for X= Br.

C10H8Cl2N2S2Zn, monoclinic, C2/c (no. 15), a = 12.317(2) Å, b = 9.868(2) Å, c = 10.947(2) Å, β = 92.37(2)°, V = 1329.3 Å3, Z = 4, Rgt(F) = 0.036, wRref(F2) = 0.132, T = 110 K.