The COVID‐19 Pandemic Not Only Poses Challenges, but Also Opens Opportunities for Sustainable Transformation

The COVID-19 pandemic has impacted social, economic, and environmental systems worldwide, slowing down and reversing the progress made in achieving the Sustainable Development Goals (SDGs). SDGs belong to the 2030 Agenda to transform our world by tackling humankind's challenges to ensure well-being, economic prosperity, and environmental protection. We explore the potential impacts of the pandemic on SDGs for Nepal. We followed a knowledge co-creation process with experts from various professional backgrounds, involving five steps: online survey, online workshop, assessment of expert's opinions, review and validation, and revision and synthesis. The pandemic has negatively impacted most SDGs in the short term. Particularly, the targets of SDG 1, 4, 5, 8, 9, 10, 11, and 13 have and will continue to have weakly to moderately restricting impacts. However, a few targets of SDG 2, 3, 6, and 11 could also have weakly promoting impacts. The negative impacts have resulted from impeding factors linked to the pandemic. Many of the negative impacts may subside in the medium and long terms. The key five impeding factors are lockdowns, underemployment and unemployment, closure of institutions and facilities, diluted focus and funds for non-COVID-19-related issues, and anticipated reduction in support from development partners. The pandemic has also opened a window of opportunity for sustainable transformation, which is short-lived and narrow. These opportunities are lessons learned for planning and action, socio-economic recovery plan, use of information and communication technologies and the digital economy, reverse migration and “brain gain,” and local governments' exercising authorities

Synthesis and characterization of some cationic ruthenium(II) complexes based on polypyridyl ligand

1571-1575The cationic mononuclear complexes [Ru(η5-arene)(K2-dpp)(Eph3)]+ (η5 -arene = C5H5 (1), C5Me5 (2), C9H7 (3); E=P (1a, 2, 3). As (1b); dpp = 2,3 -bis(2-pyridyl) pyrazine) resulting from the reactions of [Ru(η5-arene) (Eph3)2Cl] with dpp in equimolar ratio in methanol under refluxing conditions, containing both group 15 donor and a planar , olypyridyl ligand are reported here. These complexes have been isolated as their hexafluorophosphate salts and fully characterized by elemental analyses and spectral techniques, viz, IR, 1H and 31P NMR, FAB-MS and electronic spectral studies

Cationic ruthenium complexes based on planar polypyridyl ligand 2,4,6-tris (2-pyridyl)-1 ,3,5-triazine

2573-2577New cationic complexes [RU(κ3-tptz){(p-FC6H4)3P}2Cl]BF4, [RU(κ3-tptz){ (p-CH3C6H4)3P}2Cl] BF4, [RU(κ3-tptz){ (p-ClC6H4)3P}2 Cl] BF4, [RU(κ3-tptz){(p-CH3OC6H4)3P}2Cl]BF4, and [RU(κ3-tptz){(p-(CH3)2NC6H4)3P}2Cl]BF4 containing both group 15 donor and a planar polypyridyl ligand are prepared by reaction of RuCIJ.xH20 with an excess amou nt of phosphines and 2,4,6-tris(2-pyridyl)-1 ,3,5- triazine (tptz) in methanol under refluxing conditions. The complexes have been characterized by elemental analyses and spectral techniques, viz .. IR, 1H NMR, 31P NMR, FAB-MS and electronic spectral studies

DNA-binding behavior of ruthenium(II) complexes containing both group 15 donors and 2,2′:6′,2″-terpyridine

Tetrafluoroborate salts of cationic ruthenium complexes [Ru(κ3-tpy)(EPh3)2Cl]+ (tpy=2,2′:6′,2″-terpyridine; E=P, 1 or As, 2) containing both the group 15 donor ligands and tpy and their representative substitution products are reported. Weak interaction {C–H⋯X (X=Cl, F and π) and π–π interaction} studies revealed the presence of a double helical motif in complex 1, while the complex 2 assumes a single helical motif. Intercalative mode of interaction of the complexes 1 and 2 with calf thymus DNA (ctDNA) has been supported by absorption titration studies

Synthesis of electroactive multinuclear dipyrrinato complexes and Fe(III) assisted formation of α-alkoxy substituted 5-ferrocenyldipyrromethenes

The synthesis and characterization of multinuclear complexes [Pd(acac)(fcdpm)] (1), [Pd(fcdpm)2] (2), [Co(acac)(fcdpm)2(3), [Co(fcdpm)3] (4) and α-alkoxy derivatives [α-OMe-fcdpm] (5), [α-OEt-fcdpm] (6), [α-OPrn-fcdpm] (7) and [α-OBun-fcdpm] (8) (fcdpm = 5-ferrocenyldipyrromethene; acac = acetylacetone) have been described. Formation of alkoxy derivatives 5–8 takes place from highly selective Fe(III) mediated alkoxylation of fcdpm in alcohol. It has been established that yield of α-alkoxy derivatives depend on the alcohol chain length. The compounds under study have been characterized by elemental analyses, spectral (IR, 1H, 13C NMR, ESI-MS, UV-vis) and electrochemical studies (CV and DPV). Structures of 1, 3 and 5 have been verified by X-ray single crystal analyses. Structural studies revealed distorted square planar and octahedral geometry about Pd(II) and Co(III) centres. All the compounds exhibited oxidation wave due to Fc/Fc+ redox couple (0.34–0.36, 1–4; 0.24–0.25 V, 5–8)

Helical racemate architecture based on osmium(II)-polypyridyl complexes: synthesis and structural characterisation

New polypyridyl osmium(II) complexes [Os(κ3-tptz)(EPh3)2Cl]BF4 (E=P, 1; As, 2) with group 15 donor ligands are reported. Structural studies on the representative complex [Os(κ3-tptz)(PPh3)2Cl]BF4 revealed formation of helical racemates with sidewise stacking of right and left-handed anti-parallel helical strands. Salient structural features and DNA binding studies along with binding constant [6.6×103 M−1] and site size [0.12] of the complex 1 with calf thymus (ct) DNA by absorption spectroscopy are described

Structures, preparation and catalytic activity of ruthenium cyclopentadienyl complexes based on pyridyl-phosphine ligand

Ruthenium complexes [(η⁵-C₅H₅)Ru(k¹-P-PPh₂Py)(PPh₃)Cl] (1) and [(η⁵-C₅H₅)Ru(κ²-P-N-PPh₂Py)(PPh₃)]⁺ (1a) containing diphenyl-2-pyridylphosphine (PPh₂Py) are reported. Coordinated PPh₂Py in the complex [(η⁵-C₅H₅)Ru(κ¹-P-PPh₂Py)(PPh₃)Cl] (1) exhibits monodentate behavior. In presence of NH₄PF₆ in methanol at room temperature it afforded chelated complex [(η⁵-C₅H₅)Ru(κ²-P,N-PPh₂Py)(PPh₃)]⁺ (1a). Further, 1 reacted with various species viz., CH₃CN, NaCN, NH₄SCN and NaN₃ to afford cationic and neutral complexes [(η⁵-C₅H₅)Ru(κ¹-P-PPh₂Py)(PPh₃)L]⁺ and [(η⁵-C₅H₅)Ru(κ¹-P-PPh₂Py)(PPh₃)L] [L=CH₃CN (1b); CN⁻ (1c); N₃⁻ (1d) and SCN⁻ (1e)] and it’s reaction with N,N-donor chelating ligands dimethylglyoxime (H₂dmg) and 1,2-phenylenediamine (pda) gave cationic complexes [(η⁵-C₅H₅)Ru(κ¹-P-PPh₂Py)(κ²-N-N)]PF₆ [κ²-N-N=dmg (1f) and pda (1g)]. The complexes 1–1g have been characterized by physicochemical techniques and crystal structures of 1, 1a, 1c, 1e and 1f have been determined by single crystal X-ray analyses. Catalytic potential of the complex 1 has been evaluated in water under aerobic conditions. It was observed that the complex 1 selectively catalyzes reduction of aldehyde into alcohol

Interaction of ferrocene appended Ru(II), Rh(III) and Ir(III) dipyrrinato complexes with DNA/protein, molecular docking and antitumor activity

Efficacy of the ferrocene appended piano-stool dipyrrinato complexes [(η6-C6H6)RuCl(fcdpm)](1), [(η6C10H14)RuCl(fcdpm)](2), [(η6-C12H18)RuCl(fcdpm)](3) [(η5-C5Me5)RhCl(fcdpm)](4) and [(η5-C5Me5IrCl(fcdpm)] (5) [fcdpm = 5-ferrocenyldipyrromethene] toward anticancer activity have been described. Binding of the complexes with calf thymus DNA (CT-DNA) and BSA (bovine serum albumin) have been thoroughly investigated by UV–Vis and fluorescence spectroscopy. Binding constants for 1–5 (range, 104–105 M-1) validated their efficient binding with CT-DNA. Molecular docking studies revealed interaction through minor groove of the DNA, on the other hand these also interact through hydrophobic residues of the protein, particularly cavity in the subdomain IIA. In vitro anticancer activity have been scrutinized by MTT assay, acridine orange/ethidium bromide (AO/EtBr) fluorescence staining, and DNA ladder (fragmentation) assay against Dalton's Lymphoma (DL) cells. Present study revealed that rhodium complex (4) is more effective relative to ruthenium (1–3) and iridium (5) complexes