Correction to: Design, synthesis, conformational and molecular docking study of some novel acyl hydrazone based molecular hybrids as antimalarial and antimicrobial agents.

After publication of the original article [1], the following error was reported in the Results section of the Abstract: "antifungal activity against one yeast i.e. Aspergillus niger" should read: "antifungal activity against one fungus i.e. Aspergillus niger". The authors would like to confirm all antifungal activity has been screened against fungi not yeast.

Multicomponent Synthesis of Some Molecular Hybrid Containing Thiazole Pyrazole as Apoptosis Inducer.

The present study describes a multicomponent synthesis of molecular hybrid containing pyrazole, thiazole moiety using hydrazone as a linker, which have been synthesized by condensation of 1-phenyl-3-(aryl)-1H-pyrazole-4-carbaldehydes 1A-B: , thiosemicarbazide and α-bromoketones 2A-C: .The target hybrid compounds, 1-((1-phenyl-3-aryl-1H-pyrazole-4-yl)methylene)-2-(4-arylthiazole-2-yl)hydrazine 3A-F: are characterized by 1H-NMR, 13C NMR, FT-IR and mass. Apoptosis inducing ability and cytotoxic nature of all the hybrid compounds having thiazole, pyrazole and hydrazone were assessed by using biological assays viz morphological, fluorescence and tunel assays on granulosa cells of ovarian antral follicles of goat (Capra hircus) in vitro. Apoptosis was recognized and quantified using differential staining of ethidium bromide and acridine orange where apoptotic cells exhibited red fluorescence and live normal cells with intact cell membrane and normal nucleus displayed bright green fluorescence. Among the tested compounds, compound 3E: and 3B: showed the maximum potency to induce apoptosis with percentage of apoptosis 25.61±2.95and 23.45±1.46 respectively followed by 3F: (20.95±0.40) and 3D: (20.44±1.60) in comparison with control (5.14±0.44).

Design, synthesis, conformational and molecular docking study of some novel acyl hydrazone based molecular hybrids as antimalarial and antimicrobial agents.

BACKGROUND: Acyl hydrazones are an important class of heterocyclic compounds promising pharmacological characteristics. Malaria is a life-threatening mosquito-borne blood disease caused by a plasmodium parasite. In some places, malaria can be treated and controlled with early diagnosis. However, some countries lack the resources to do this effectively. RESULTS: The present work involves the design and synthesis of some novel acyl hydrazone based molecular hybrids of 1,4-dihydropyridine and pyrazole (5a-g). These molecular hybrids were synthesised by condensation of 1,4-dihydropyridin-4-yl-phenoxyacetohydrazides with differently substituted pyrazole carbaldehyde. The final compound (5) showed two conformations (the major, E, s-cis and the minor, E, s-trans) as revealed by NMR spectral data and further supported by the energy calculations (MOPAC2016 using PM7 method). All the synthesised compounds were screened for their in vitro antimalarial activities against chloroquine-sensitive malaria parasite Plasmodium falciparum (3D7) and antimicrobial activity against Gram positive bacteria i.e. Bacillus cereus, Gram negative bacteria i.e. Escherichia coli and antifungal activity against one fungus i.e. Aspergillus niger [corrected]. All these compounds were found more potent than chloroquine and clotrimazole, the standard drugs. CONCLUSIONS: In vitro antiplasmodial IC50 value of the most potent compound 5d was found to be 4.40 nM which is even less than all the three reference drugs chloroquine (18.7 nM), pyrimethamine (11 nM) and artimisinin (6 nM). In silico binding study of compound 5d with plasmodial cysteine protease falcipain-2 indicated the inhibition of falcipain-2 as the probable reason for the antimalarial potency of compound 5d. All the compounds had shown good to excellent antimicrobial and antifungal activities.

Synthesis of novel inhibitors of α-amylase based on the thiazolidine-4-one skeleton containing a pyrazole moiety and their configurational studies.

Postprandial hyperglycemia can be controlled by delaying the absorption of glucose resulting from carbohydrate digestion. α-Amylase is the initiator of the hydrolysis of polysaccharides, and therefore developing α-amylase inhibitors can lead to development of new treatments for metabolic disorders like diabetes mellitus. In the present work, we set out to rationally develop α-amylase inhibitors based on the thiazolidine-4-one scaffold. The structures of all these newly synthesized hybrids were confirmed by spectroscopic analysis (IR, 1H-NMR, MS). The appearance of two sets of signals for some protons in 1H NMR revealed the existence of a mixture of 2E,5Z (37.1-42.0%) and 2Z,5Z isomers (58.4-62.8%), which was further supported by DFT studies. All the newly synthesized compounds have potential inhibitory properties as revealed through in vitro α-amylase inhibition activity. Compound 5a at 100 µg mL-1 concentration showed a remarkable inhibition of 90.04%. In vitro α-amylase inhibition was further supported by docking studies of compound 5a against the active site of human pancreatic α-amylase (PDB ID: ; 2QV4). The docking studies revealed that the bonding interactions found between 5a and human pancreatic α-amylase are similar to those responsible for α-amylase inhibition by acarbose.