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The synthesis of small heterocycles under neat mechanochemical conditions is of great interest in the field of drug design because most of the commercially available drugs contain at least one heterocyclic unit. The sodium borohydride (NaBH4) promoted reductive cyclization to fused dihydrofuran under grinding technique is one of the compendium additions for the clean future. The development of chemoselective reduction under silica‐gel supported conditions represents significant progress in organic synthesis, offering a versatile and efficient method for selective reduction of specific functional groups within complex molecules. Synthesis of isoindole derivatives from the chemoselective reduce product via a sustainable short synthetic pathway is another significant process of our newly developed protocol. Finally, antileishmanial investigations of our synthesized compounds establish a soft bridge between biology and chemistry. [ABSTRACT FROM AUTHOR]

An efficient and short synthesis of fused dihydroisoquinolines, diaryl substituted pyridine derivatives in good to high yields has been established by using an environmentally safe, solvent‐metal‐oxidant‐free tandem approach. In this article, we discuss how the electrocyclic reaction is more pronounced in the solid phase in the presence of urea, whereas the typical aza‐Michael addition is more prominent in presence of arylamine in the solution phase for 3‐(2‐formylcycloalkenyl)acrylic ester derivative substrates. The wide range of substrates and urea‐promoted neat synthesis made our approach more significant in medical and also analytical science. Moreover, an isoquinoline alkaloid decumbenine B analogue has been synthesized by using our newly developed neat methodology. We have also investigated the photophysical properties of the synthesized fused dihydroisoquinoline derivatives. One of the synthesized molecules was used as a sensor for the selective detection of toxic picric acid. Therefore, the effective neat synthesis and molecular sensing applications of these compounds made our approach more exciting in the field of heterocyclic chemistry. [ABSTRACT FROM AUTHOR]

Background: Osteoarthritis (OA) of the knee is the most frequent progressive degenerative joint disease with a 20% prevalence in India. Many patients with knee OA elect to avoid surgery, and others are poor surgical candidates due to medical comorbidities. Aims: This study aimed to determine 3-, 6-, and 12-month clinical outcomes of genicular nerve cooled radiofrequency ablation (CRFA) for the treatment of chronic pain due to primary knee OA. Study Settings and Design: The present study, a single-armed prospective observational study, was conducted in a tertiary care hospital between March 2020 and December 2021. The genicular nerve CRFA treatments were performed in chronic knee OA patients with a radiological grade of 2 (mild), 3 (moderate), or 4 (severe) (Kellgren and Lawrence system) not responding to conservative therapies for at least 6 months. A total of 70 patients were enrolled in the study. Out of this, 62 patients were finally analyzed for the study. Methods: All the patients received procedural sedation and were placed in the supine position on the operating table. Fluoroscopy-guided CRF genicular nerve ablation was performed using anatomic landmarks at superior lateral, superior medial, and inferior medial sites. Further needle position was confirmed by motor and sensory stimulation. Each target was sequentially lesioned for 2 min and 30 s at a set temperature of 60°C. The average procedure duration was 40 min for the index knee. The patient was discharged on the same day. All patients were followed up in person after 3, 6, and 12 months. Patients answered the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire (96 points) and Numeric Rating Scale (NRS) pain score (0 -- no pain and 10 -- maximum pain) before the procedure and during each follow-up after treatment. Statistical Analysis: Results were analyzed using Pearson's Chi-square test, Fisher's exact test, and ANOVA as appropriate. P >0.05 was considered statistically significant. Results: The average mean baseline pain score was 9.00 (8.41 ± 0.66) and the mean WOMAC score was 80.00 (80.02 ± 6.92). The pain score (NRS) and WOMAC score at 3-, 6-, and 12-month intervals after postprocedure follow-up were reduced significantly from the baseline level (P < 0.001). Total 91.93% (57/62) of the patients successfully responded (≥50% improvement from the baseline was a good response) to the treatment according to NRS pain score during 3- and 6-month follow-up visits. Then, it was reduced to 77.41% (48/62) during 12 months of follow-up visits. Similarly, the average median WOMAC score was reduced to 25.00 (28.80 ± 10.82), 25.00 (29.35 ± 11.12), and 34.00 (34.96 ± 11.28) during a subsequent follow-up visit at 3, 6, and 12 months. Hence, the response to the cooled radiofrequency treatment was good (≥50% improvement) throughout the study period of 12 months according to the NRS pain score and the global subjective improvement score (WOMAC score). There were a few 11 (17.74%) minor complications, e.g. mild swelling and pain were reported in the immediate postprocedure period. Moreover, only 4 (6.45%) patients had late complication as hypoesthesia over shin bone in our study. Conclusions: CRFA of the genicular nerve in chronic knee OA provides long-term pain relief and improved function for at least a 12-month duration without any significant complications. [ABSTRACT FROM AUTHOR]

A study concerning the synthesis of the (pyridylazo)oxime ligand to promote a mononuclear oximato-O coordination is presented. Experiments include hydrazone nitrosation.

A mild, efficient and stable copper iodide nanoparticle (CuI NP)‐catalyzed regioselective synthesis of 3‐nitro‐2‐arylimidazo[1,2‐a]pyridines was developed. Substituted 2‐amino pyridines successfully reacted with both electron‐rich and electron‐deficient β‐nitro styrenes to produce the desired products in good to excellent yields. Hot filtration tests confirmed the heterogeneous nature of the CuI NPs. The nanocatalyst showed good reusability up to three consecutive cycles without any significant loss in its activity and product yield, confirmed by high‐resolution transmission electron microscopy (HR‐TEM) analysis. Use of molecular oxygen as oxidant is advantageous from an economic and environmental point of view. [ABSTRACT FROM AUTHOR]

Research was conducted to examine the synthesis, redox characterization, spectra an single-crystal X-ray structures of the two isomers of the ruthenium-(II) complexes RuL2Cl2. The isomers were chromatographically isolated with the green isomer quantitatively changed to the blue isomer upon refluxing in a high boiling solvent. Results indicate that the Ru(III)/Ru(II) couple in the blue complexes at 0.7-0.8 V and in the green complexes at 0.6-0.7 V against SCE and two azo reductions.

The azo-amine system in the form of electroneutral diamagnetic bis chelates of palladium is presented. The chelated azo amines incorporate 10 ligand pi electrons while their synthetic precursor is the bis(azooximate) Pd-(Ra)2. The azo-amine frame can be looked upon as the intermediate member in the azo-azo, azo-amine, imine-imine sequence. Results with palladium indicate that the chelate frame can sustain more ligand pi electrons and anionic charge as the number of nitrogen increases.

A one-electron-one-proton electroprotic transformation enables the conversion of trans-Pt(pbo)2 (Hpbo = PhN double bond Nc(Ph) double bond NOH), prepared from a reaction between Hpbo and K2PtCl4, into a cis-dimer complex. Both trans and cis complexes exhibit diamagnetism in the solid state, and in solution the dimer undergoes dissociation. X-ray and spectroscopic studies help characterize these complexes. In the dimer, dz2-dz2 and azo-azo interactions exhibit significant contribution to binding, while the unpaired electron in the monomer is significantly azo-pi in nature.

The effects of variable metal valence on the dimensions and bonding around the M = Ru species were analyzed by utilizing two Ru complexes with a general formula of RuCl2(L)(HL)z (HL = PhC(NOH)NNPh; z = 1-, 0). The ruthenium complexes were synthesized as Et4N+ salts from the reaction of trans-RuCl2(Me2SO)4 with PhC(NOH)NNPh. The RuCl2(L)(HL)z complexes exhibited distorted octahedral geometries with linear RuCl2 fragments. Furthermore, the ruthenium complexes exhibited unsymmetrical O-H-...O hydrogen bonding.

Background: Use of suxamethonium is associated with an increase in intraocular pressure (IOP) and may be harmful for patients with penetrating eye injuries. The purpose of our study was to observe the efficacy of dexmedetomidine for prevention of rise in IOP associated with the administration of suxamethonium and endotracheal intubation. Methods: Sixty-six American Society of Anaesthesiologists I or II patients undergoing general anaesthesia for non-ophthalmic surgery were included in this randomized, prospective, clinical study. Patients were allocated into three groups to receive 0.4 µg/kg dexmedetomidine (group D4), 0.6 µg/kg dexmedetomidine (group D6) or normal saline (group C) over a period of 10 min before induction. IOP, heart rate and mean arterial pressure were recorded before and after the premedication, after induction, after suxamethonium injection and after endotracheal intubation. Results: Fall in IOP was observed following administration of dexmedetomidine. IOP increased in all three groups after suxamethonium injection and endotracheal intubation, but it never crossed the baseline value in group D4 as well as in group D6. Fall in mean arterial pressure was noticed after dexmedetomidine infusion, especially in the D6 group. Conclusion: Dexmedetomidine (0.6 µg/kg as well as 0.4 µg/kg body weight) effectively prevents rise of IOP associated with administration of suxamethonium and endotracheal intubation. However, dexmedetomidine 0.6 µg/kg may cause significant hypotension. Thus, dexmedetomidine 0.4 µg/kg may be preferred for prevention of rise in IOP. [ABSTRACT FROM AUTHOR]

Comparing the efficacy, safety and outcome of percutaneous intrervention for Budd-Chiari Syndrome (BCS) patients with bilirubin less than 3 and 3–6 mg dl−1. 188 BCS patients having serum bilirubin ≤6 mg dl−1 and underwent percutaneous interventions were divided into two groups based on bilirubin level: 151 patients having bilirubin <3 mg dl−1 were included in Group 1; and 37 patients having bilirubin 3–6 mg dl−1 were included in Group 2. Both group were compare for technical success (successful recanalization of hepatic venous stenosis or creation of portocaval shunt with post-procedure gradient ≤5 mm of Hg), Safety (procedure-related mortality/morbidity or patient required transplantation) and outcome (resolution of clinical symptoms and survival). Technical success was 94.7% in Group 1–89.1% in Group 2 with overall success rate was 93.6%. No significant differences observed between the two groups in regards to procedure related complication. Overall transplant-free survival at 1 and 5 years after intervention in both groups was 96.3 and 91.2% respectively. 1-year and 5-year survivals in Group 1 was 96.7%, and 93.1%, whereas Group 2 was 94.6 and 90.1% with no statically significantly difference between the two groups (p = 0.59). Percutaneous intervention results are good in patients having bilirubin up to 6 mg dl−1, i.e. mild to moderate liver dysfunctions. Technical success, survival and outcome of percutaneous intervention in BCS patients having serum bilirubin 3–6 mg dl−1 was comparable to patients having bilirubin level <3 mg dl−1. Percutaneous intervention treatment is suitable for treatment for symptomatic BCS patients having bilirubin up to 6 mg dl−1. [ABSTRACT FROM AUTHOR]

A convenient method for the synthesis of magnetically recyclable palladium nanoparticles (Fe3O4‐Pd) is described. The catalytic application of the Fe3O4‐Pd nanoparticles was explored for the first time in oxidative coupling between amides and olefins. p‐Toluenesulfonic acid plays a significant role in the oxidative amidation reaction. The reaction proceeds at room temperature, resulting in (Z)‐enamides under ambient air in the absence of co‐catalyst and ligand. The superparamagnetic nature of Fe3O4‐Pd facilitates easy, quantitative recovery of the catalyst from a reaction mixture, and it can be reused for up to three consecutive cycles with a slight decrease in catalytic activity. [ABSTRACT FROM AUTHOR]

An efficient and short synthesis of fused dihydroisoquinolines, diaryl substituted pyridine derivatives in good to high yields has been established by using an environmentally safe, solvent-metal-oxidant-free tandem approach. In this article, we discuss how the electrocyclic reaction is more pronounced in the solid phase in the presence of urea, whereas the typical aza-Michael addition is more prominent in presence of arylamine in the solution phase for 3-(2-formylcycloalkenyl)acrylic ester derivative substrates. The wide range of substrates and urea-promoted neat synthesis made our approach more significant in medical and also analytical science. Moreover, an isoquinoline alkaloid decumbenine B analogue has been synthesized by using our newly developed neat methodology. We have also investigated the photophysical properties of the synthesized fused dihydroisoquinoline derivatives. One of the synthesized molecules was used as a sensor for the selective detection of toxic picric acid. Therefore, the effective neat synthesis and molecular sensing applications of these compounds made our approach more exciting in the field of heterocyclic chemistry., (© 2023 Wiley-VCH GmbH.)

A novel and efficient cerium-catalyzed tandem oxidation and intermolecular ring cyclization of vicinal diols with hydrazones has been achieved for the regioselective synthesis of pyrazole derivatives. The corresponding 1,3-di- and 1,3,5-trisubstituted pyrazoles were obtained in moderate to excellent yields. The reaction has the advantages of mild conditions, easily available starting materials, broad substrate scope and good functional group tolerance.

The (pyridylazo)oxime ligand (C(5)H(4)N)N=NC(=NOH)C(6)H(4)R(p), HRL (R = H, Me), has been synthesized with the objective of promoting the very rare mononuclear oximato-O coordination. The synthesis involves hydrazone nitrosation. HRL reacts with M(ClO(4))(2).6H(2)O, affording [M(RL)(2)] (M = Mn, Fe), and X-ray structure determinations have indeed revealed the presence of the desired oximato-O coordination mode in the distorted octahedral MN(4)O(2) sphere characterized by a 2-fold axis of symmetry relating the two tridentate ligands, all chelate rings being five-membered. The M-N and M-O distances are relatively short (1.84-1.99 Å), consistent with spin-pairing (M = Mn, S = (1)/(2); M = Fe, S = 0). The M-N bond length trend, Mn(II) > Fe(II), is in accord with the larger radius of the low-spin Mn(II) atom. The M-O length order is, however, Mn(II) < Fe(II). This reversal occurs because of the rigidity of the ligand skeleton. Significant M-azo back-bonding is present (N=N length approximately 1.30 Å). [Mn(RL)(2)] displays hyperfine-split axial EPR spectra (g( parallel) approximately 1.98, g( perpendicular) approximately 2.06, A( parallel) approximately 170 G, A( perpendicular) approximately 65 G) in frozen solution as well as in polycrystalline [Fe(RL)(2)] lattices. The quasireversible Fe(III)/Fe(II) couple of [Fe(RL)(2)] has E(1/2) approximately 0.7 V. The oxidized complex [Fe(RL)(2)]PF(6) has been electrosynthesized. It is low-spin (S = (1)/(2)) and displays axial EPR spectra (g( parallel) approximately 1.98, g( perpendicular) approximately 2.14) in frozen solution. The Mn(II) --> Mn(III) oxidation ( approximately 1.0 V) in [Mn(RL)(2)] is irreversible. Crystal data for [Mn(HL)(2)].CH(2)Cl(2): crystal system monoclinic, space group I2/a, a = 14.142(7) Å, b = 10.721(7) Å, c = 16.933(10) Å, beta = 93.01(4) degrees, Z = 4. Crystal data for [Fe(HL)(2)].CH(2)Cl(2): crystal system monoclinic, space group I2/a, a = 14.254(6) Å, b = 10.742(6) Å, c = 16.719(8) Å, beta = 92.35(4) degrees, Z = 4.