Microwave-assisted Palladium catalysed C-H acylation with aldehydes. Synthesis and diversification of 3-acylthiophenes

The use of MW allows the efficient palladium(II)-catalysed C-3 acylation of thiophenes with aldehydes via C(sp2)-H activation for the synthesis of (cyclo)alkyl/aryl thienyl ketones (43 examples). Compared to standard thermal...

A Fatal Case of Severe Acute Organophosphorus Pesticide Poisoning Complicated with Secondary Hemophagocytic Lympho-Histiocytosis, Severe Lower Intestinal Hemorrhage and Intestinal Mucormycosis

A man in his 50’s, under influence of alcohol, accidentally ingested a pesticide, and was referred for further management and admitted to our hospital. An empty can of Curacron® was found at the site in his farm where he took the alleged pesticide. This raised the suspicion of organophosphorus pesticide poisoning and he was managed at two medical centres before getting admitted to our hospital. His hospital course was complicated with multiorgan dysfunction, shock, respiratory failure and intermediate syndrome. On day five he developed secondary hemophagocytic lymphohistiocytosis (sHLH) and had hematochezia on day six. Colonoscopy revealed multiple circumferential ulcerations in descending and sigmoid colon with luminal narrowing. Biopsy of colonic tissue showed evidence of intestinal Mucormycosis. The clinical presentation of organophosphorus pesticide poisoning in this patient was complicated with multiple issues and included sHLH, chemical gastroenteritis, hemorrhagic ulcers and intestinal zygomycosis. The organophosphorus pesticide ingested by the patient was a 50% emulsifiable concentrate of profenofos along with vegetable oil, soyabean oil and polyglycol ether alkyl aryl sulphate calcium salt 5.25% w/w as an emulsifier/spreading agent. The management of the patient is discussed. Due to the possibility of the emulsifier adhering to the gastrointestinal tract and causing mucosal injury, it is necessary to identify the drug composition and ingredients of the pesticide as soon as possible when managing organophosphorus poisoning.

Indazole Derivatives Effective against Gastrointestinal Diseases

Background: In this fast-growing lifestyle, humans are in the race against time to cope up with busy schedule. Less exercise, consumption of high calorie-low fiber food and stress take us one step closer towards digestive dysfunction. Dysfunctional digestive system causes various gastrointestinal disorders like constipation, IBS, UC, diarrhea, gastrointestinal tract immobility, hyperglycemia, hemorrhoids, fistula, anal fissures, stomach cancer, hepatocellular carcinoma, pancreatic cancer, colon cancer and metabolic syndrome. Amongst various natural and synthetic indazole derivatives nigellicine, nigellamine, nigellidine, zanubrutinib and SCH772984 showed prominent results to cure various gastrointestinal disorders. Objective: In this manuscript, we focus on the importance of indazole derivatives in the treatment of various gastrointestinal diseases. Results and Conclusion: In the treatment of IBS, four positions (R1, R2, R3 and R4) of indazole were mainly substituted with aromatic aldehyde/substituted methyl, aromatic acid/formamide, benzamide/sulfonamide and methyl groups, respectively. In case of diarrhea and metabolic syndrome treatment, substitutions with benzyl/isopropyl/acetaldehyde (R1 position) and carboxamide/formamide (R2 position) of indazole play a critical role. Also, in the treatment of diabetes melitus, all six positions of indazole derivative were substituted with substituted aryl/alkyl/aromatic acid, substituted formamide, substituted acetamide/hydrazide group, halo aryl, substituted aryl/aromatic acid and a long chain of alkyl-aryl alcohol groups, respectively. In the treatment of gastrointestinal cancers, all six positions of indazole derivative were substituted with benzylamide (R1), octanediamide/benzamide/formamide (R2), carbaldehyde (R4) and substituted phenyl (R5 and R6) groups, respectively. Six receptors (6NP0, 2YME, 4EFU, 4WZ8, 5U4W and 7KKP) associated with GI disorders (co-crystallized with indazole derivative) were identified. Analysis of the receptors showed that co-crystalized ligand molecules were well-interacted with receptors via pie-pie interaction, co-ordinate and sigma bonding within 4 Å distance. As per Ramachandran plot analysis, more than 90% of the amino acid residues were present in the most favored region. So, if sufficient focuses are imposed on the development of newer indazole derivatives to treat gastrointestinal diseases, it will work as a boon to society.

Photophysical, photostability, and ROS generation properties of new trifluoromethylated quinoline-phenol Schiff bases

A new series of ten examples of Schiff bases, namely (E)-2-(((2-alkyl(aryl/heteroaryl)-4-(trifluoromethyl)quinolin-6-yl)imino)methyl)phenols 3, was easily synthesized with yields of up to 91% from the reactions involving a series of 2-(R-substituted) 6-amino-4-(trifluoromethyl)quinolines 1 and 4(5)-R1-substituted salicylaldehydes 2 – in which alkyl/aryl/heteroaryl for 2-R-substituents are Me, Ph, 4-MeC6H4, 4-FC6H4, 4-NO2C6H4, and 2-furyl, and R1-substituents are 5-NEt2, 5-OCH3, 4-Br, and 4-NO2. Complementarily, the Schiff bases showed low to good quantum fluorescence yield values in CHCl3 (Φf = 0.12–0.80), DMSO (Φf = 0.20–0.75) and MeOH (Φf = 0.13–0.85). Higher values of Stokes shifts (SS) were observed in more polar solvents (DMSO; 65–150 nm and MeOH; 65–130 nm) than in CHCl3 (59–85 nm). Compounds 3 presented good stability under white-LED irradiation conditions and moderate ROS generation properties were observed.

I. Magnesium Promoted Coupling of Carbodiimides and Terminal Acetylenes, II. Bismuth Compounds Supported by Di(amido) Chelating Ligands

<p>The work presented in this thesis is divided into two parts, both of which investigate the chemistry of main group elements supported by N,N'-donor ligands. Part 1 investigates the use of Mg(mesC{NCy}₂)(N{SiMe₃}₂)(THF) (mes = 2,4,6- Me₃C₆H₃, Cy = C₆H₁₁) as a pre-catalyst for the coupling of terminal acetylenes to carbodiimides. A catalytic cycle for the reaction is proposed, based on a series of stoichiometric reactions. Ligand redistribution via Schlenk equilibria is a prominent feature of the proposed catalytic cycle. The scope of catalysis was also investigated, indicating a strong dependence on the sterics and electronics of both the carbodiimide and the terminal acetylene. Investigation of other magnesium species identified other pathways into the catalytic cycle. Part 2 explores the derivitisation of Bi(Me₂Si{NAr})Cl (Ar = 2,6-i-Pr₂C₆H₃) to form a number of novel bismuth(III) species of the general formula Bi(Me₂Si{NAr})X (X = alkyl, aryl, amide, aryloxide, phosphide). In addition, a number of cationic bismuth species have been isolated from the reaction of Bi(Me₂Si{NAr})Cl with ECl₃ (E = Al, Ga). Preliminary investigations reveal that the amide and aryloxide derivatives are active as initiators for the ring-opening polymerisation of lactide and ε-caprolactone. A number of bismuth(III) compounds bearing the related di(amido)ether ligands [O(Me₂Si{NAr})₂]²⁻ have also been synthesised.</p>

I. Magnesium Promoted Coupling of Carbodiimides and Terminal Acetylenes, II. Bismuth Compounds Supported by Di(amido) Chelating Ligands

<p>The work presented in this thesis is divided into two parts, both of which investigate the chemistry of main group elements supported by N,N'-donor ligands. Part 1 investigates the use of Mg(mesC{NCy}₂)(N{SiMe₃}₂)(THF) (mes = 2,4,6- Me₃C₆H₃, Cy = C₆H₁₁) as a pre-catalyst for the coupling of terminal acetylenes to carbodiimides. A catalytic cycle for the reaction is proposed, based on a series of stoichiometric reactions. Ligand redistribution via Schlenk equilibria is a prominent feature of the proposed catalytic cycle. The scope of catalysis was also investigated, indicating a strong dependence on the sterics and electronics of both the carbodiimide and the terminal acetylene. Investigation of other magnesium species identified other pathways into the catalytic cycle. Part 2 explores the derivitisation of Bi(Me₂Si{NAr})Cl (Ar = 2,6-i-Pr₂C₆H₃) to form a number of novel bismuth(III) species of the general formula Bi(Me₂Si{NAr})X (X = alkyl, aryl, amide, aryloxide, phosphide). In addition, a number of cationic bismuth species have been isolated from the reaction of Bi(Me₂Si{NAr})Cl with ECl₃ (E = Al, Ga). Preliminary investigations reveal that the amide and aryloxide derivatives are active as initiators for the ring-opening polymerisation of lactide and ε-caprolactone. A number of bismuth(III) compounds bearing the related di(amido)ether ligands [O(Me₂Si{NAr})₂]²⁻ have also been synthesised.</p>