Structures of rhodopsin in complex with G-protein-coupled receptor kinase 1.

G-protein-coupled receptor (GPCR) kinases (GRKs) selectively phosphorylate activated GPCRs, thereby priming them for desensitization1. Although it is unclear how GRKs recognize these receptors2-4, a conserved region at the GRK N terminus is essential for this process5-8. Here we report a series of cryo-electron microscopy single-particle reconstructions of light-activated rhodopsin (Rho*) bound to rhodopsin kinase (GRK1), wherein the N terminus of GRK1 forms a helix that docks into the open cytoplasmic cleft of Rho*. The helix also packs against the GRK1 kinase domain and stabilizes it in an active configuration. The complex is further stabilized by electrostatic interactions between basic residues that are conserved in most GPCRs and acidic residues that are conserved in GRKs. We did not observe any density for the regulator of G-protein signalling homology domain of GRK1 or the C terminus of rhodopsin. Crosslinking with mass spectrometry analysis confirmed these results and revealed dynamic behaviour in receptor-bound GRK1 that would allow the phosphorylation of multiple sites in the receptor tail. We have identified GRK1 residues whose mutation augments kinase activity and crosslinking with Rho*, as well as residues that are involved in activation by acidic phospholipids. From these data, we present a general model for how a small family of protein kinases can recognize and be activated by hundreds of different GPCRs.

Sulfoproteomics Workflow with Precursor Ion Accurate Mass Shift Analysis Reveals Novel Tyrosine Sulfoproteins in the Golgi.

Tyrosine sulfation in the Golgi of secreted and membrane proteins is an important post-translational modification (PTM). However, its labile nature has limited analysis by mass spectrometry (MS), a major reason why no sulfoproteome studies have been previously reported. Here, we show that a phosphoproteomics experimental workflow, which includes serial enrichment followed by high resolution, high mass accuracy MS, and tandem MS (MS/MS) analysis, enables sulfopeptide coenrichment and identification via accurate precursor ion mass shift open MSFragger database search. This approach, supported by manual validation, allows the confident identification of sulfotyrosine-containing peptides in the presence of high levels of phosphorylated peptides, thus enabling these two sterically and ionically similar isobaric PTMs to be distinguished and annotated in a single proteomic analysis. We applied this approach to isolated interphase and mitotic rat liver Golgi membranes and identified 67 tyrosine sulfopeptides, corresponding to 26 different proteins. This work discovered 23 new sulfoproteins with functions related to, for example, Ca2+-binding, glycan biosynthesis, and exocytosis. In addition, we report the first preliminary evidence for crosstalk between sulfation and phosphorylation in the Golgi, with implications for functional control.

Synchrotron-Infrared Microspectroscopy of Live Leishmania major Infected Macrophages and Isolated Promastigotes and Amastigotes.

The prevalence of neglected tropical diseases (NTDs) is advancing at an alarming rate. The NTD leishmaniasis is now endemic in over 90 tropical and sub-tropical low socioeconomic countries. Current diagnosis for this disease involves serological assessment of infected tissue by either light microscopy, antibody tests, or culturing with in vitro or in vivo animal inoculation. Furthermore, co-infection by other pathogens can make it difficult to accurately determine Leishmania infection with light microscopy. Herein, for the first time, we demonstrate the potential of combining synchrotron Fourier-transform infrared (FTIR) microspectroscopy with powerful discrimination tools, such as partial least squares-discriminant analysis (PLS-DA), support vector machine-discriminant analysis (SVM-DA), and k-nearest neighbors (KNN), to characterize the parasitic forms of Leishmania major both isolated and within infected macrophages. For measurements performed on functional infected and uninfected macrophages in physiological solutions, the sensitivities from PLS-DA, SVM-DA, and KNN classification methods were found to be 0.923, 0.981, and 0.989, while the specificities were 0.897, 1.00, and 0.975, respectively. Cross-validated PLS-DA models on live amastigotes and promastigotes showed a sensitivity and specificity of 0.98 in the lipid region, while a specificity and sensitivity of 1.00 was achieved in the fingerprint region. The study demonstrates the potential of the FTIR technique to identify unique diagnostic bands and utilize them to generate machine learning models to predict Leishmania infection. For the first time, we examine the potential of infrared spectroscopy to study the molecular structure of parasitic forms in their native aqueous functional state, laying the groundwork for future clinical studies using more portable devices.

Medicinal chemistry and biomedical applications of bismuth-based compounds and nanoparticles.

Bismuth as a relatively non-toxic and inexpensive metal with exceptional properties has numerous biomedical applications. Bismuth-based compounds are used extensively as medicines for the treatment of gastrointestinal disorders including dyspepsia, gastric ulcers and H. pylori infections. Recently, its medicinal application was further extended to potential treatments of viral infection, multidrug resistant microbial infections, cancer and also imaging, drug delivery and biosensing. In this review we have highlighted the unique chemistry and biological chemistry of bismuth-209 as a prelude to sections covering the unique antibacterial activity of bismuth including a description of research undertaken to date to elucidate key molecular mechanisms of action against H. pylori, the development of novel compounds to treat infection from microbes beyond H. pylori and the significant role bismuth compounds can play as resistance breakers. Furthermore we have provided an account of the potential therapeutic application of bismuth-213 in targeted alpha therapy as well as a summary of the biomedical applications of bismuth-based nanoparticles and composites. Ultimately this review aims to provide the state of the art, highlight the untapped biomedical potential of bismuth and encourage original contributions to this exciting and important field.

Main Group Metal-Mediated Transformations of Imines.

Main-group-metal-mediated transformations of imines have earned a valued place in the synthetic chemist's toolbox. Their versatility allows the simple preparation of various nitrogen containing compounds. This review will outline the early discoveries including metallation, addition/cyclisation and metathesis pathways, followed by the modern-day use of imines in synthetic methodology. Recent advances in imine C-F activation protocols are discussed, alongside revisiting "classic" imine reactivity from a sustainable perspective. Developments in catalytic methods for hydroelementation of imines have been reviewed, highlighting the importance of s-block metals in the catalytic arena. Whilst stoichiometric transformations in alternative reaction media such as deep eutectic solvents or water have been summarised. The incorporation of imines into flow chemistry has received recent attention and is summarised within.

Interactions of Non-steroidal Anti-inflammatory Drugs and Their Bismuth Analogues (BiNSAIDs) with Biological Membrane Mimics at Physiological pH.

Previous studies have demonstrated the potential for non-steroidal anti-inflammatory drugs (NSAIDs), in particular aspirin, to be used as chemopreventives for colorectal cancer; however, a range of unwanted gastrointestinal side effects limit their effectiveness. Due to the role of bismuth in the treatment of gastrointestinal disorders, it is hypothesized that bismuth-coordinated NSAIDs (BiNSAIDs) could be used to combat the gastrointestinal side effects of NSAIDs while still maintaining their chemopreventive potential. To further understand the biological activity of these compounds, the present study examined four NSAIDs, namely, tolfenamic acid (tolfH), aspirin (aspH), indomethacin (indoH), and mefenamic acid (mefH) and their analogous homoleptic BiNSAIDs ([Bi(L)3]n), to determine how these compounds interact with biological membrane mimics composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) or a mixture of POPC and cholesterol. Electrical impedance spectroscopy studies revealed that each of the NSAIDs and BiNSAIDs influenced membrane conductance, suggesting that temporary pore formation may play a key role in the previously observed cytotoxicity of tolfH and Bi(tolf)3. Quartz crystal microbalance with dissipation monitoring showed that all the compounds were able to interact with membrane mimics composed of solely POPC or POPC/cholesterol. Finally, neutron reflectometry studies showed changes in membrane thickness and composition. The location of the compounds within the bilayer could not be determined with certainty; however, a complex interplay of interactions governs the location of small molecules, such as NSAIDs, within lipid membranes. The charged nature of the parent NSAIDs means that interactions with the polar headgroup region are most likely with larger hydrophobic sections, potentially leading to deeper penetration.

Metal Compounds against Neglected Tropical Diseases.

Many first-line treatments for neglected tropical diseases identified by the World Health Organization (WHO) are limited by one or more of the following: the development of drug resistance, toxicity, and side effects, lack of selectivity, narrow therapeutic indices, route of administration, and bioavailability. As such, there is an urgent need to develop viable alternatives to overcome these limitations. The following review provides an overview of all existing metal complexes studied and evaluates the status of these complexes on the respective disease of choice.

Impaired replication elongation in Tetrahymena mutants deficient in histone H3 Lys 27 monomethylation.

Replication of nuclear DNA occurs in the context of chromatin and is influenced by histone modifications. In the ciliate Tetrahymena thermophila, we identified TXR1, encoding a histone methyltransferase. TXR1 deletion resulted in severe DNA replication stress, manifested by the accumulation of ssDNA, production of aberrant replication intermediates, and activation of robust DNA damage responses. Paired-end Illumina sequencing of ssDNA revealed intergenic regions, including replication origins, as hot spots for replication stress in ΔTXR1 cells. ΔTXR1 cells showed a deficiency in histone H3 Lys 27 monomethylation (H3K27me1), while ΔEZL2 cells, deleting a Drosophila E(z) homolog, were deficient in H3K27 di- and trimethylation, with no detectable replication stress. A point mutation in histone H3 at Lys 27 (H3 K27Q) mirrored the phenotype of ΔTXR1, corroborating H3K27me1 as a key player in DNA replication. Additionally, we demonstrated interactions between TXR1 and proliferating cell nuclear antigen (PCNA). These findings support a conserved pathway through which H3K27me1 facilitates replication elongation.

Pervasive Charge Solvation Permeates Native-like Protein Ions and Dramatically Influences Top-down Sequencing Data.

Post-translational modifications create a diverse mixture of proteoforms, leading to substantial challenges in linking proteomic information to disease. Top-down sequencing of intact proteins and multiprotein complexes offers significant advantages in proteoform analysis, but achieving complete fragmentation for such precursor ions remains challenging. Intact proteins that undergo slow-heating generally fragment via charge directed (i.e., mobile proton) or charge remote fragmentation pathways. Our efforts seek to alter this paradigm by labeling proteins with trimethyl pyrylium (TMP), which forms a stable, positively charged label at lysine residues. Fixing positive charges to the protein sequence reduces the availability of mobile protons, driving fragmentation to charge remote channels. Furthermore, we demonstrate that capping acidic side chains with carbodiimide chemistry obstructs this pathway, restoring charge-directed fragmentation and resulting in more even coverage of the protein sequence. With large amounts of fixed charge and few mobile protons, we demonstrate that it is also possible to direct fragmentation almost exclusively to lysine residues containing the charged label. Finally, our data indicate that when electrosprayed under native conditions, protein ions possess an immense capacity to accommodate excess positive charge. Molecular dynamics simulations of such ions bearing intrinsically charged labels reveal evidence of numerous charge solvation processes, including the preferential formation of helices that solvate charged labels through interactions with their macro-dipoles. Thus, these studies reveal the extent to which intact gas-phase protein ions are capable of solvating charge, and provide the most complete indication to date of the extensive physical forces opposing the goal of comprehensive top-down protein sequencing.

Ruthenium(II)-Arene Thiocarboxylates: Identification of a Stable Dimer Selectively Cytotoxic to Invasive Breast Cancer Cells.

RuII -arene complexes provide a versatile scaffold for novel anticancer drugs. Seven new RuII -arene-thiocarboxylato dimers were synthesized and characterized. Three of the complexes (2 a, b and 5) showed promising antiproliferative activities in MDA-MB-231 (human invasive breast cancer) cells, and were further tested in a panel of fifteen cancerous and noncancerous cell lines. Complex 5 showed moderate but remarkably selective activity in MDA-MB-231 cells (IC50 =39±4 µm Ru). Real-time proliferation studies showed that 5 induced apoptosis in MDA-MB-231 cells but had no effect in A549 (human lung cancer, epithelial) cells. By contrast, 2 a and b showed moderate antiproliferative activity, but no apoptosis, in either cell line. Selective cytotoxicity of 5 in aggressive, mesenchymal-like MDA-MB-231 cells over many common epithelial cancer cell lines (including noninvasive breast cancer MCF-7) makes it an attractive lead compound for the development of specifically antimetastatic Ru complexes with low systemic toxicity.

Bismuth(III) Flavonolates: The Impact of Structural Diversity on Antibacterial Activity, Mammalian Cell Viability and Cellular Uptake.

A series of homoleptic and heteroleptic bismuth(III) flavonolate complexes derived from six flavonols of varying substitution have been synthesised and structurally characterised. The complexes were evaluated for antibacterial activity towards several problematic Gram-positive (Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococcus (VRE)) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. The cell viability of COS-7 (monkey kidney) cells treated with the bismuth flavonolates was also studied to determine the effect of the complexes on mammalian cells. The heteroleptic complexes [BiPh(L)2 ] (in which L=flavonolate) showed good antibacterial activity towards all of the bacteria but reduced COS-7 cell viability in a concentration-dependent manner. The homoleptic complexes [Bi(L)3 ] exhibited activity towards the Gram-positive bacteria and showed low toxicity towards the mammalian cell line. Bismuth uptake studies in VRE and COS-7 cells treated with the bismuth flavonolate complexes indicated that Bi accumulation is influenced by both the substitution of the flavonolate ligands and the degree of substitution at the bismuth centre.

Is Bismuth Really the "Green" Metal? Exploring the Antimicrobial Activity and Cytotoxicity of Organobismuth Thiolate Complexes.

Antimicrobial resistance is becoming an ever-increasing threat for human health. Metal complexes and, in particular, those that incorporate bismuth offer an attractive alternative to the typically used organic compounds to which bacteria are often able to develop resistance determinants. Herein we report the synthesis, characterization, and biological evaluation of a series of homo- and heteroleptic bismuth(III) thiolates incorporating either one (BiPh2L), two (BiPhL2), or three (BiL3) sulfur-containing azole ligands where LH = tetrazolethiols or triazolethiols (thiones). Despite bismuth typically being considered a nontoxic heavy metal, we demonstrate that the environment surrounding the metal center has a clear influence on the safety of bismuth-containing complexes. In particular, heteroleptic thiolate complexes (BiPh2L and BiPhL2) display strong antibacterial activity yet are also nonselectively cytotoxic to mammalian cells. Interestingly, the homoleptic thiolate complexes (BiL3) were shown to be completely inactive toward both bacterial and mammalian cells. Further biological analysis of the complexes revealed the first insights into the biological mode of action of these particular bismuth thiolates. Scanning electron microscopy images of methicillin-resistant Staphylococcus aureus (MRSA) cells have revealed that the cell membrane is the likely target site of action for bismuth thiolates against bacterial cells. This points toward a nonspecific mode of action that is likely to contribute to the poor selectivity's demonstrated by the bismuth thiolate complexes in vitro. Uptake studies suggest that reduced cellular uptake could explain the marked difference in activity between the homo- and heteroleptic complexes.

Lithium-Bromide Exchange versus Nucleophilic Addition of Schiff's base: Unprecedented Tandem Cyclisation Pathways.

By exploring lithium-bromide exchange reactivity of aromatic Schiff's bases with tert-butyllithium (tBuLi), we have revealed unprecedented competitive intermolecular and intramolecular cascade annulation pathways, leading to valuable compounds, such as iso-indolinones and N-substituted anthracene derivatives. A series of reaction parameters were probed, including solvent, stoichiometry, sterics and organolithium reagent choice, in order to understand the influences that limit such ring-closing pathways. With two viable reactivity options for the organolithium on the imine; namely, nucleophilic addition or lithium-bromide exchange, a surprising competitive nature was observed, where nucleophilic addition dominated, even under cryogenic conditions. Considering the most commonly used solvents for lithium-bromide exchange, tetrahydrofuran (THF) and diethyl ether (Et2 O), contrasting reactivity outcomes were revealed with nucleophilic addition promoted in THF, while Et2 O yielded almost double the conversion of cyclic products than in THF.

Disruption of ribosome assembly in yeast blocks cotranscriptional pre-rRNA processing and affects the global hierarchy of ribosome biogenesis.

In higher eukaryotes, pre-rRNA processing occurs almost exclusively post-transcriptionally. This is not the case in rapidly dividing yeast, as the majority of nascent pre-rRNAs are processed cotranscriptionally, with cleavage at the A2 site first releasing a pre-40S ribosomal subunit followed by release of a pre-60S ribosomal subunit upon transcription termination. Ribosome assembly is driven in part by hierarchical association of assembly factors and r-proteins. Groups of proteins are thought to associate with pre-ribosomes cotranscriptionally during early assembly steps, whereas others associate later, after transcription is completed. Here we describe a previously uncharacterized phenotype observed upon disruption of ribosome assembly, in which normally late-binding proteins associate earlier, with pre-ribosomes containing 35S pre-rRNA. As previously observed by many other groups, we show that disruption of 60S subunit biogenesis results in increased amounts of 35S pre-rRNA, suggesting that a greater fraction of pre-rRNAs are processed post-transcriptionally. Surprisingly, we found that early pre-ribosomes containing 35S pre-rRNA also contain proteins previously thought to only associate with pre-ribosomes after early pre-rRNA processing steps have separated maturation of the two subunits. We believe the shift to post-transcriptional processing is ultimately due to decreased cellular division upon disruption of ribosome assembly. When cells are grown under stress or to high density, a greater fraction of pre-rRNAs are processed post-transcriptionally and follow an alternative processing pathway. Together, these results affirm the principle that ribosome assembly occurs through different, parallel assembly pathways and suggest that there is a kinetic foot-race between the formation of protein binding sites and pre-rRNA processing events.

2D and 3D Coordination Networks of Polynuclear Bismuth Oxido/Hydroxido Sulfonato Clusters from Low Temperature Solid-State Metathesis Reactions.

Solid-state metathesis (SSM) reactions between Bi(NO3 )3 ⋅5 H2 O and potassium benzene-1,2-disulfonate (=1,2-BDSK2 ), sodium benzene-1,3-disulfonate (=1,3-BDSNa2 ) allows access to the first 2D, {[Bi6 O4 (OH)4 (1-2BDS)2 (NO3 )2 ⋅4 H2 O]⋅11 H2 O}∞ and {[Bi22 O24 (OH)6 (1,3-BDS)6 ⋅12 DMSO]⋅3 DMSO⋅4 H2 O}∞ , and 3D, {[Bi6 O4 (OH)4 (1,3-BDS)3 ⋅4 H2 O]⋅6 H2 O}∞ , polymeric networks of sulfonato encapsulated polynuclear bismuth oxido/hydroxido clusters.

Homo- and Heteroleptic Coordination Polymers and Oxido Clusters of Bismuth(III) Vinylsulfonates.

The synthesis and characterization of six homo- and heteroleptic coordination polymers and oxido clusters of bismuth(III) vinylsulfonates are reported. The solvent-mediated reaction of BiPh3 and vinylsulfonic acid in ethanol produces [{Ph2 Bi(O3 SCH=CH2 )}n ] (1), which crystallizes as a one-dimensional coordination polymer as a result of bridging sulfonato ligands accompanied by intermolecular Bi⋅⋅⋅ π(arene) London dispersion interactions. In solution, compound 1 equilibrates to give [{PhBi(O3 SCH=CH2 )2 }n ] (2) and BiPh3 . Compound 2 is obtained as a single product by the reaction of BiPh3 with vinylsulfonic acid in acetonitrile and crystallizes as a one-dimensional coordination polymer. The homoleptic vinylsulfonate [{Bi(O3 SCH=CH2 )3 }n ] (3) was isolated as a two-dimensional coordination polymer, which is quite moisture sensitive, but did not provide a distinct polynuclear bismuth oxido cluster upon hydrolysis. However, by treatment of [Bi6 O4 (OH)4 (NO3 )6 ]⋅H2 O or [Bi38 O45 (OMc)24 (dmso)9 (H2 O)2 ]⋅2 DMSO⋅5 H2 O (OMc=methacrylate) with vinylsulfonic acid, such a cluster, namely, [Bi9 O7 (OH)(O3 SCH=CH2 )11 (dmso)11 ](O3 SCH=CH2 )⋅3 DMSO (4), is available as the main product. Starting from the hexanuclear bismuth oxido nitrate, another cluster, [Bi38 O45 (NO3 )8 (O3 SCH=CH2 )14 (dmso)18 ](O3 SCH=CH2 )2 ⋅2 DMSO (5), was observed as a co-crystallizing side product, which upon further hydrolysis afforded [Bi38 O45 (NO3 )6 (OH)4 (O3 SCH=CH2 )12 (dmso)23 (H2 O)2 ](O3 SCH=CH2 )2 ⋅2 H2 O (6).

Bismuth Phosphinates in Bi-Nanocellulose Composites and their Efficacy towards Multi-Drug Resistant Bacteria.

A series of poorly soluble phenyl bis-phosphinato bismuth(III) complexes [BiPh(OP(=O)R1 R2 )2 ] (R1 =R2 =Ph; R1 =R2 =p-OMePh; R1 =R2 =m-NO2 Ph; R1 =Ph, R2 =H; R1 =R2 =Me) have been synthesised and characterised, and shown to have effective antibacterial activity against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE). The bismuth complexes were incorporated into microfibrillated (nano-) cellulose generating a bismuth-cellulose composite as paper sheets. Antibacterial evaluation indicates that the Bi-cellulose materials have analogous or greater activity against Gram positive bacteria when compared with commercial silver based additives: silver sulfadiazine loaded at 0.43 wt % into nanocellulose produces a 10 mm zone of inhibition on the surface of agar plates containing S. aureus whereas [BiPh(OP(=O)Ph2 )2 ] loaded at 0.34 wt % produces an 18 mm zone of inhibition. These phenyl bis-phosphinato bismuth(III) complexes show potential to be applied in materials in healthcare facilities, to inhibit the growth of bacteria capable of causing serious disease.

Synthesis of CID-cleavable protein crosslinking agents containing quaternary amines for structural mass spectrometry.

Two novel cyclic quaternary amine crosslinking probes are synthesized for structural mass spectrometry of protein complexes in solution and for analysis of protein interactions in organellar and whole cell extracts. Each exhibits high aqueous solubility, excellent protein crosslinking efficiencies, low collision induced dissociation (CID) energy fragmentation efficiencies, high stoichiometries of reaction, increased charges of crosslinked peptide ions, and maintenance of overall surface charge balance of crosslinked proteins.

Large-Scale Analysis of Kinase Signaling in Yeast Pseudohyphal Development Identifies Regulation of Ribonucleoprotein Granules.

Yeast pseudohyphal filamentation is a stress-responsive growth transition relevant to processes required for virulence in pathogenic fungi. Pseudohyphal growth is controlled through a regulatory network encompassing conserved MAPK (Ste20p, Ste11p, Ste7p, Kss1p, and Fus3p), protein kinase A (Tpk2p), Elm1p, and Snf1p kinase pathways; however, the scope of these pathways is not fully understood. Here, we implemented quantitative phosphoproteomics to identify each of these signaling networks, generating a kinase-dead mutant in filamentous S. cerevisiae and surveying for differential phosphorylation. By this approach, we identified 439 phosphoproteins dependent upon pseudohyphal growth kinases. We report novel phosphorylation sites in 543 peptides, including phosphorylated residues in Ras2p and Flo8p required for wild-type filamentous growth. Phosphoproteins in these kinase signaling networks were enriched for ribonucleoprotein (RNP) granule components, and we observe co-localization of Kss1p, Fus3p, Ste20p, and Tpk2p with the RNP component Igo1p. These kinases localize in puncta with GFP-visualized mRNA, and KSS1 is required for wild-type levels of mRNA localization in RNPs. Kss1p pathway activity is reduced in lsm1Δ/Δ and pat1Δ/Δ strains, and these genes encoding P-body proteins are epistatic to STE7. The P-body protein Dhh1p is also required for hyphal development in Candida albicans. Collectively, this study presents a wealth of data identifying the yeast phosphoproteome in pseudohyphal growth and regulatory interrelationships between pseudohyphal growth kinases and RNPs.

Formation of Group†11 Bismuth Sulfide Nanoparticles Using Bismuth Dithioates under Mild Conditions.

The formation of mixed-metal sulfides with the general structure AgBiS2 and Cu3 BiS2 by a simple two-step process utilizing bismuth dithiocarboxylates as Bi and S precursors is described. A sonochemical reaction of Bi2 O3 with six different aryl dithioic acids: dithiobenzoic acid (BDT-H), 4-methoxydithiobenzoic acid (4-MBDT-H), 3-methyldithiobenzoic acid (3-MBDT-H), 2-mesitylenedithioic acid (2-MDT-H), 4-fluorodithiobenzoic acid (4-FBDT-H), and 2-thiophenedithioic acid (2-TDT-H) resulted in the corresponding complexes: [Bi(BDT)3 ] 1, [Bi(4-MBDT)3 ] 2, [{Bi(3-MBDT)3 }2 ⋅C7 H8 ] (32 ⋅C7 H8 ), [Bi(2-MDT)3 ] 4, [Bi(4-FBDT)3 ] 5 and [Bi(2-TDT)3 ] 6. Microwave irradiation of these bismuth(III)aryldithioate complexes with AgNO3 or CuCl under mild reaction conditions (140 °C) resulted in the respective mixed-metal sulfides. Attempt to synthesize AuBiS2 using similar reaction protocols were unsuccessful, resulting only in the formation of elemental Au0 , S8 and BiOCl.