We have observed five sulphur-bearing molecules in foreground diffuse molecular clouds lying along the sight-lines to five bright continuum sources. We have used the GREAT instrument on SOFIA to observe the SH 1383 GHz 2 Π 3/2 J = 5/2 ← 3/2 lambda doublet toward the star-forming regions W31C, G29.96-0.02, G34.3+0.1, W49N and W51, detecting foreground absorption towards all five sources; and the EMIR receivers on the IRAM 30 m telescope at Pico Veleta to detect the H 2 S 1 10 −1 01 (169 GHz), CS J = 2−1 (98 GHz) and SO 3 2 −2 1 (99 GHz) transitions. Upper limits on the H 3 S + 1 0 −0 0 (293 GHz) transition were also obtained at the IRAM 30 m. In nine foreground absorption components detected towards these sources, the inferred column densities of the four detected molecules showed relatively constant ratios, with N(SH)/N(H 2 S) in the range 1.1−3.0, N(CS)/N(H 2 S) in the range 0.32−0.61, and N(SO)/N(H 2 S) in the range 0.08−0.30. The column densities of the sulphur-bearing molecules are very well correlated amongst themselves, moderately well correlated with CH (a surrogate tracer for H 2 ), and poorly correlated with atomic hydrogen. The observed SH/H 2 ratios -in the range 5 to 26 × 10 −9 -indicate that SH (and other sulphur-bearing molecules) account for 1% of the gas-phase sulphur nuclei. The observed abundances of sulphur-bearing molecules, however, greatly exceed those predicted by standard models of cold diffuse molecular clouds, providing further evidence for the enhancement of endothermic reaction rates by elevated temperatures or ion-neutral drift. We have considered the observed abundance ratios in the context of shock and turbulent dissipation region (TDR) models. Using the TDR model, we find that the turbulent energy available at large scale in the diffuse ISM is sufficient to explain the observed column densities of SH and CS. Standard shock and TDR models, however, fail to reproduce the column densities of H 2 S and SO by a factor of about 10; more elaborate shock models -in which account is taken of the velocity drift, relative to H 2 , of SH molecules produced by the dissociative recombination of H 3 S + -reduce this discrepancy to a factor ∼3.

A series of Rh III and Ir III piano-stool complexes of the form [(η 5 -Cp* R )M(NHC)Cl 2 ] was synthesized and characterized, including 12 X-ray crystallographic structures. The antimicrobial properties of these complexes were screened against a variety of microbes, with several achieving high activities, most notably against Mycobacterium smegmatis (MICs as low as 0.45 μM). In general, the Rh complexes were more potent than their Ir analogues, and activity increased with the hydrophobicity of the Cp* R and NHC ligands. Article pubs.acs.org/Organometallics

SARS-CoV-2 emerged in 2019 as a devastating viral pathogen with no available preventative or treatment to control what led to the current global pandemic. The continued spread of the virus and increasing death toll necessitate the development of effective antiviral treatments to combat this virus. To this end, we evaluated a new class of organometallic complexes as potential antivirals. Our findings demonstrate that two pentamethylcyclopentadienyl (Cp*) rhodium piano stool complexes, Cp*Rh(1,3-dicyclohexylimidazol-2-ylidene)Cl2 (complex 2) and Cp*Rh(dipivaloylmethanato)Cl (complex 4), have direct virucidal activity against SARS-CoV-2. Subsequent in vitro testing suggests that complex 4 is the more stable and effective complex and demonstrates that both 2 and 4 have low toxicity in Vero E6 and Calu-3 cells. The results presented here highlight the potential application of organometallic complexes as antivirals and support further investigation into their activity.

The title complexes, (η4-cycloocta-1,5-diene)bis(1,3-dimethylimidazol-2-ylidene)iridium(I) iodide, [Ir(C5H8N2)2(C8H12)]I, (1) and (η4-cycloocta-1,5-diene)bis(1,3-diethylimidazol-2-ylidene)iridium(I) iodide, [Ir(C7H12N2)2(C8H12)]I, (2), were prepared using a modified literature method. After carrying out the oxidative addition of the amino acid L-proline to [Ir(COD)(IMe)2]I in water and slowly cooling the reaction to room temperature, a suitable crystal of 1 was obtained and analyzed by single-crystal X-ray diffraction at 100 K. Although this crystal structure has previously been reported in the Pbam space group, it was highly disordered and precise atomic coordinates were not calculated. A single crystal of 2 was also obtained by heating the complex in water and letting it slowly cool to room temperature. Complex 1 was found to crystallize in the monoclinic space group C2/m, while 2 crystallizes in the orthorhombic space group Pccn, both with Z = 4.