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Background: Diabetic neuropathic pain exerts strong as well as negative influence on both survival and quality of life of the patient. This pain is difficult to treat with conventional analgesics. Now a days, different medicinal herbs are highlighted due to their wide range of beneficial application with less side effects. In this regards Spirulina platensis is well known for its wide range of biological activities. Objective: To assess the effects of oral administration of Spirulina platensis on cold allodynia and chemical allodynia in diabetic neuropathic pain in Long Evans rats.Materials and Methods: This study was conducted in the Department of Physiology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Shahbag, Dhaka from March 2017 to February 2019. Twenty four (24) Long Evans rats, having 150 to 200 grams body weight (on the basis of treatments), the rats were divided into Group I (normal saline 5 ml/kg body weight) and Group II (Spirulina platensis 400 mg/kg body weight). All the supplementations were given once daily for consecutive 21 days orally and last doses were given one hour before the pain evaluation tests. Further on the basis of experiments, previously grouped rats were divided into subgroup ‘a’(cold tail immersion test), and ‘b’ (formalin test). Data were expressed as mean±SEM and were statistically analyzed by SPSS (Version 16) using independent sample ‘t’ test to compare mean value between two groups. (p 0.05 was considered as the level of significance).Results: Spirulina platensis showed significantly higher tail flick latency (p 0.001) in cold tail immersion test. S. platensis demonstrated significantly lowered jerking frequency (p 0.001,p 0.01,p 0.001, respectively); the duration of licking (p 0.001,p 0.05,p 0.001, respectively) and the duration of flexing (p 0.001, non-significant 0.01, respectively) in early, inter and late phases of formalin test in compared to those of control. Conclusion: S. platensis attenuates cold allodynia and chemical allodynia diabetic neuropathic pain in rat model. KYAMC Journal Vol. 13, No. 04, January 2023: 208-213

The separation of xylene isomers is one of the most challenging tasks in the petrochemical industry. Herein, we developed an efficient adsorptive molecular sieving strategy using crystalline trianglimine macrocycle (1) to separate the elusive m-xylene isomer from an equimolar xylenes mixture with over 91% purity. The selectivity is attributed to the capture of the preferred guest with size/shape selectivity and C–H⋯π interactions. Moreover, the trianglimine crystals are readily recyclable due to the reversible transformation between the guest-free and guest-loaded structures.

Predicting, controlling, understanding, and elucidating the phase transition from gel to crystal are highly important for the development of various functional materials with macroscopic properties. Here, we show a detailed and systematic description of the self-assembly process of an enantiopure trianglimine macrocyclic host from gel to single crystals. This proceeds via an unprecedented formation of capsule-like or right-handed helix superstructures as metastable products, depending on the nature of the guest molecule. Mesitylene promotes the formation of capsule-like superstructures, whereas toluene results in the formation of helices as intermediates during the course of crystallization. Single-crystal results demonstrate that the crystals obtained via the direct self-assembly from the gel phase are different from the crystals obtained from the stepwise assembly of the intermediate superstructures. Hence, investigating the phase-transition superstructures that self-assemble through the process of crystallization can unravel new molecular ordering with unexplored host-guest interactions. Such understanding will provide further tools to control hierarchical assemblies at the molecular level and consequently design or dictate the properties of evolved materials.

The direct exploitation of ‘electrons’ as reagents in synthetic organic transformations is on the verge of a renaissance by virtue of its greenness, sustainability, atom economy, step economy and inherent safety. Achieving stereocontrol in such organic electrochemical reactions remains a major synthetic challenge and hence demands great expertise. This review provides a comprehensive discussion of the details of stereoselective organic electrochemical reactions along with the synthetic accomplishments achieved with these methods.

The separation of styrene (ST) and ethylbenzene (EB) mixtures is of great importance in the petrochemical and plastics industries. Current technology employs multiple cycles of energy-intensive distillation due to the very close boiling points of ST and EB. Here, we show that the molecular sieving properties of easily scalable and stable trianglimine crystals offer ultrahigh selectivity (99%) for styrene separation. The unique molecular sieving properties of trianglimine crystals are corroborated by DFT calculations, suggesting that the incorporation of the nonplanar EB requires a significant deformation of the macrocyclic cavity whereas the planar ST can be easily accommodated in the cavity.

Herein, we report the synthesis and characterization of the metal free low valent fluoroborylene [(Me-cAAC)2BF] (1) stabilized by cyclic (alkyl)(amino) carbene (cAAC). The fluoroborylene 1 is obtained by the reductive defluorination of Me-cAAC:BF3 with 2.0 equivalents of KC8 in the presence of 1.0 equivalent of Me-cAAC. Due to its highly electron rich nature, 1 underwent one-electron oxidation with 1.0 equivalent of lithium tetrakis(pentafluorophenyl)borate [LiB(C6F5)4] to form the radical cation [(Me-cAAC)2BF]˙+[B(C6F5)4]- (2). DFT studies suggested that the lone pair of electrons is localized on the boron atom in 1, which explains its unprecedented reactivity. Both compounds 1 and 2 were characterized by X-ray crystallography. The radical cation 2 was studied by EPR spectroscopy. peerReviewed

The reaction of the ferrous complex [LFe(NCMe)2](OTf)2 (1), which contains a macrocyclic tetracarbene as ligand (L), with Na(OCP) generates the OCP−‐ligated complex [LFe(PCO)(CO)]OTf (2) together with the dinuclear μ‐phosphido complex [(LFe)2P](OTf)3 (3), which features an unprecedented linear Fe‐(μ‐P)‐Fe motif and a “naked” P‐atom bridge that appears at δ=+1480 ppm in the 31P NMR spectrum. 3 exhibits rich redox chemistry, and both the singly and doubly oxidized species 4 and 5 could be isolated and fully characterized. X‐ray crystallography, spectroscopic studies, in combination with DFT computations provide a comprehensive electronic structure description and show that the Fe‐(μ‐P)‐Fe core is highly covalent and structurally invariant over the series of oxidation states that are formally described as ranging from FeIIIFeIII to FeIVFeIV. 3–5 now add a higher homologue set of complexes to the many systems with Fe‐(μ‐O)‐Fe and Fe‐(μ‐N)‐Fe core structures that are prominent in bioinorganic chemistry and catalysis., The naked truth: Using a macrocyclic tetracarbene ligand scaffold and Na(OCP) as a P‐atom transfer reagent has allowed a diiron complex to be isolated with a “naked” P bridge. The complex exhibits rich redox chemistry, and both the singly and doubly oxidized species could be isolated and fully characterized. The unprecedented linear Fe‐(μ‐P)‐Fe core is highly covalent and is structurally invariant over three oxidation states.

A novel and efficient methodology for the synthesis of 6H-benzo[c]chromenes, 6H-benzo[c]chromen-6-ones, carbazoles, dibenzofurans, dibenzooxepins has been developed. The reaction goes through intramolecular O-/N-arylations with sp2C–Br bonds via typical SNAr pathway in presence of potassium-tert-butoxide base.

We have developed a novel and efficient methodology for the intramolecular aryl C–H oxidative lactonization of 2-arylbenzaldehyde using a low-cost CuCl catalyst and TBHP as the oxidant at room temperature. We applied the methodology to the synthesis of a series of dibenzopyranones.

An efficient hetero-annulation protocol has been developed for the construction of 4,5,6-trisubstituted-1,3-dihydroisobenzofurans via palladium-catalyzed domino carbopalladation of bromoenynes and internal alkynes. The reaction followed domino intramolecular Heck cyclization (5-exo-dig) and termination of the resulting diene with an internal alkyne to give highly substituted isobenzofurans in moderate to good yields.

The presence of an FeV(O) species has been postulated as the active intermediate for the oxidation of both C–H and C=C bonds in the Rieske dioxygenase family of enzymes. Understanding the reactivity of these high valent iron–oxo intermediates, especially in an aqueous medium, would provide a better understanding of these enzymatic reaction mechanisms. The formation of an FeV(O) complex at room temperature in an aqueous CH3CN mixture that contains up to 90% water using NaOCl as the oxidant is reported here. The stability of FeV(O) decreases with increasing water concentration. We show that the reactivity of FeV(O) toward the oxidation of C–H bonds, such as those in toluene, can be tuned by varying the amount of water in the H2O/CH3CN mixture. Rate acceleration of up to 60 times is observed for the oxidation of toluene upon increasing the water concentration. The role of water in accelerating the rate of the reaction has been studied using kinetic measurements, isotope labeling experiments, and density functional theory (DFT) calculations. A kinetic isotope effect of ∼13 was observed for the oxidation of toluene and d8-toluene showing that C–H abstraction was involved in the rate-determining step. Activation parameters determined for toluene oxidation in H2O/CH3CN mixtures on the basis of Eyring plots for the rate constants show a gain in enthalpy with a concomitant loss in entropy. This points to the formation of a more-ordered transition state involving water molecules. To further understand the role of water, we performed a careful DFT study, concentrating mostly on the rate-determining hydrogen abstraction step. The DFT-optimized structure of the starting FeV(O) and the transition state indicates that the rate enhancement is due to the transition state’s favored stabilization over the reactant due to enhanced hydrogen bonding with water., An FeV(O) complex was generated at room temperature in H2O/CH3CN mixtures (

An efficient method has been developed for the synthesis of bis-exocyclic conjugated diene containing 1,2,3,4-tetrahydroquinoline derivatives via palladium-catalyzed intramolecular Heck cyclization of (2-bromo-allyl)-(2-phenylethynyl-phenyl)-amines. The reaction followed 6-exo-dig cyclization to yield the desired products in moderate to good yields.

Phthalides have been synthesized exclusively in one pot via Pd-free Sonogashira coupling. A Cu-catalyzed domino Sonogashira coupling and 5-exo-dig cyclization between suitable substituted ortho-bromobenzoic acids and terminal alkynes afforded phthalides in good yields under mild reaction conditions.

Agriculture sector as a whole has developed and emerged immensely with the infusion of science and technology. But this latest emergence is not capable of plummeting the ignorance of women labour as an integral part of this industry. In developing countries like India, agriculture continues to absorb and employ female work force but fails to give them recognition of employed/hired labour. Women constituted 38% of the agricultural labour force in developing countries. It is also estimated that 45.3% of the agricultural labour force consists of women. But a large number of women have remained as "invisible workers”. Since there has been concern expressed regarding the gap between women’s actual economic participation and public perception of it several researchers have attempted to overcome this invisibility through gendered empirical research studies for using on gender analysis and gender roles. This piece of research is highlighting the trend of female participation in agriculture across various Indian states. The secondary data collated for the research is used to study the growth trend of the agricultural worker from 1961-2001. Analysis is done to categorize the states on their identical behaviour of participation in agriculture by hierarchical clustering of economically active female in agriculture based on measurements like coefficient of variation, compound growth rate and work participation rate.

An efficient method for the synthesis of halo-carbolines has been developed via Pd-catalysed formation of C–N bonds through Csp2-H/N–H activation of 4-methyl-N-[2-(pyridine-3-yl)phenyl] benzenesulfonamide derivatives. Pd(OAc)2 in the presence of Cu(OAc)2 as oxidant afforded halo-carbolines in good to excellent yields with tolerance to a variety of substituents.

Ni55Mn22Ga23−xAlx (0 ≤ x ≤ 5) melt spun ribbons homogenized at 1073 K for 30 h exhibited an elevation in martensitic transformation onsets and a reduction in Curie temperature with increase in Al content. The phenomenon has been attributed to different site occupancy by Al, exchange coupling and paramagnetic martensite during thermal and magnetic transitions. Transmission Electron microscopy revealed systematic patterns of dislocations in alloy with x = 1, which become denser at high Al content. X = 1 alloy revealed high magnetic field induced strain (MFIS) value it is attributed to a critical combination of austenite and martensite phase.

An Fe(V)(O) complex has been synthesized from equimolar solutions of (Et4N)2[Fe(III)(Cl)(biuret-amide)] and mCPBA in CH3CN at room temperature. The Fe(V)(O) complex has been characterized by UV-vis, EPR, Mossbauer, and HRMS and shown to be capable of oxidizing a series of alkanes having C-H bond dissociation energies ranging from 99.3 kcal mol(-1) (cyclohexane) to 84.5 kcal mol(-1) (cumene). Linearity in the Bell-Evans-Polayni graph and the finding of a large kinetic isotope effect suggest that hydrogen abstraction is engaged the rate-determining step.

Two efficient hetero-annulation protocols have been developed for the synthesis of stable substituted c-fused thiophene derivatives with moderate to high yield. 3-(2-formyl-phenyl)-acrylic acid esters afforded benzo[c]thiophenes in the presence of phosphorus pentasulfide in refluxing benzene while 3-(2-formyl-cycloalkenyl)α,β-unsaturated esters resulted in the formation of c-fused thiophene derivatives when reacted with sodium sulfide in refluxing tetrahydrofuran.