Search

Alzheimer's disease (AD) is a neurological disorder that progresses gradually but irreversibly leading to dementia and is difficult to prevent and treat. There is a considerable time window in which the progression of the disease can be intervened. Scientific advances were required to help the researchers to identify the effective methods for the prevention and treatment of disease. This research was designed to investigate potential mediators for the remedy of AD, five new carboxylate amide zinc complexes (AAZ9-AAZ13) were synthesized and characterized by spectroscopic and physicochemical techniques. The biological evaluation was carried out based on the cholinesterase inhibitory mechanism. The preparation methodology provided the effective synthesis of targeted moieties. The in vitro pharmacological activities were evaluated involving AChE/BChE inhibition and antioxidant potential. All synthesized compounds displayed activity against both enzymes in higher or comparable to the standard drug Galantamine, a reversible inhibitor but the results displayed by compound AAZ10 indicated IC 50 of 0.0013 µM (AChE) and 0.061 µM (BChE) as high values for dual AChE/BChE inhibition with potent anti-oxidant results. Structure activity relationship (SAR) indicated that the potent activity of compound AAZ10 appeared due to the presence of nitro clusters at the ortho position of an aromatic ring. The potent synthesized compound AAZ10 was also explored for the in-vivo Anti-Alzheimer activity and anti-oxidant activity. Binding approaches of all synthesized compounds were revealed through molecular docking studies concerning binding pockets of enzymes that analyzed the best posture interaction with amino acid (AA) residues providing an appreciable understanding of enzyme inhibitory mechanisms. Results indicate that synthesized zinc (II) amide carboxylates can behave as an effective remedy in the treatment of Alzheimer's disease.Communicated by Ramaswamy H. Sarma.

This research was planned to synthesize cyano-acetate derivatives of succinimide and evaluate its comparative biological efficacy as anti-inflammatory, anti-cholinesterase and anti-diabetic, which was further validated by molecular docking studies. The three cyano-acetate derivatives of succinimide including compound 23 Methyl 2-cyano-2-(2,5-dioxopyrrolidin-3-yl)acetate, compound 31 Methyl 2-cyano-2-(1-methyl-2,5-dioxopyrrolidin-3-yl)acetate and compound 44 Methyl 2-cyano-2-(1-ethyl-2,5-dioxopyrrolidin-3-yl) acetate were synthesized. The mentioned compounds were checked for in vitro anti-inflammatory, anti-cholinesterase and anti-diabetic (α-amylase inhibition) activity. To validate the in vitro results, computational studies were carried out using molecular operating environment to analyse the BE, i.e. binding energies of all synthesized compounds against the respective enzymes. The Compounds 23, 31, 44 exhibited anti-inflammatory via inhibiting COX-2 (IC 50 value of 204.08, 68.60 and 50.93 µM, respectively), COX-1 (IC 50 value of 287, 185, and 143 µM, respectively) and 5-LOX (IC 50 value of 138, 50.76 and 20, 87 µM respectively) . They exhibited choline-mimetic potential, such as compound 23, 31 and 44 inhibited AChE enzyme (IC 50 value of 240, 174, and 134 µM, respectively) and BChE enzyme (IC 50 value of 203, 134 and 97 µM, respectively). The Compounds 23, 31, 44 exhibited anti-diabetic effect via inhibiting α-amylase enzyme (IC 50 values of 250, 106 and 60 µM, respectively). Molecular docking studies revealed that the synthesized compounds have good binding affinity in the binding pockets of AChE, BChE, COX-2, 5-LOX and α-amylase enzyme and showed high binding energies. The synthesized succinimide derivatives, i.e. compound 23, 31, 44 showed marked inhibitory activities against cyclooxygenase, lipoxygenase, α-amylase and cholinesterase enzymes. Among these three, compound 44 and 31 showed strong anti-inflammatory and anti-diabetic activity while they displayed moderate anti-cholinesterase activity supported by molecular docking results.Communicated by Ramaswamy H. Sarma.

Due to a lack of therapeutic options for the pathological condition of leishmaniasis, which is characterized by polymorphic lesions and skin surface infections, Leishmania genus parasites damaged dermis and mucosa. There was a need to synthesize and characterize some new complexes. This study evaluated the biological activities preferably anti-Leishmanial activity of organotin (IV) containing sulphonyl hydrazide derivatives. A series of six new organotin (IV) complexes 1-6 labeled as R2SnL2; R = Methyl (1), Butyl (2), Phenyl (3) and R3SnL; R = Methyl (4), Butyl (5), Phenyl (6) has been synthesized as reflux method derived from N'- (2,4-dinitrophenyl)-4-methylphenylsulfonylhydrazide (L). All compounds were characterized through FT-IR, 1HNMR, 13CNMR, and elemental analysis. Structural analysis confirms the formation of six complexes (1-6). All derivatives have been screened for their pharmacological activities. Interestingly, compound 1 showed promising activity against leishmania promastigotes with low cytotoxicity. All results were further elaborated through docking studies performed on leishmania donovoni synthetase PDB: ID 3QW3 that acts as an essential building block for the viability of Leishmania promastigotes. This research effectively synthesized sulphonyl hydrazide ligand and its six new organotin (IV) derivatives, which were tested for biological properties such as antibacterial, anti-fungal, anti-oxidant, and ideally anti-leishmanial activity and cytotoxicity. Studies have confirmed that these compounds have the potency to be a good candidate against leishmaniasis. Computational studies were carried out to recognize the binding affinities for leishmania donovoni synthetase.Communicated by Ramaswamy H. Sarma.

In search of suitable therapy for the management of Alzheimer's disease, this study was designed to evaluate metal complexes against its biochemical targets. Zinc metal carboxylates ( AAZ1-AAZ6 ) were evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The antioxidant in combination with anticholinesterase activity can be considered as an important target in the management of Alzheimer's disease. Therefore, these compounds were also screened for ABTS and DPPH free radical scavenging activity. In AChE inhibition assay, we noticed encouraging IC 50 values of 33.07 and 59.52 µM for compounds AAZ5 and AAZ3 , respectively. However, when we tested BChE activity, we observed an outstanding IC 50 of 0.056 µM for compound AAZ6 . Amazingly all of our compounds ( AAZ1-AAZ6 ) were proved to be strong antioxidants which actively supplement the anti-Alzheimer's activity. The majority of our compounds exhibited lower IC 50 values than the standard ascorbic acid in both DPPH and ABTS assays. We also correlated our results with molecular docking studies. Results elaborated that AAZ1 and AAZ5 exhibit strong interactions with amino acids HIS 362, HIS 398, GLU 306 ARG 289 and SER 237 inside binding pocket of targeted protein. In remarks, we can claim that our synthesized zinc metal carboxylates have strong potency to manage Alzheimer's disease on both anticholinesterase and antioxidant targets. Communicated by Ramaswamy H. Sarma.