Convenient and Scalable Synthesis of 2,3-Dihydroquinazolin-4(1H)-one Derivatives and Their Anticancer Activities

An efficient and mild InBr₃-catalyzed approach to synthesize 2,3-dihydroquinazolin-4(1H)-one derivatives (3a–3aa) has been developed. Notably, all the products were isolated by recrystallization and the reaction is accessible on a gram scale. Moreover, the reactions only require 10–60 min. All the synthesized compounds were evaluated for their in vitro anticancer activity against four human cancer cell lines.     

Surface and Antimicrobial Properties of N-Palmitoyl Amino Acid–Based Surfactants

Synthesized sodium N-pamitoyl amino acids were evaluated for surface and antimicrobial properties and compared with sodium lauryl sulfate (SLS). Emulsion stability of the amino acid surfactants and calcium tolerance of the sodium N-palmitoyl isoleucine were better as compared to SLS. Wetting ability and foaming properties of the palmitic acid-based surfactants were inferior to SLS. N-Acyl amino acids exhibited better antibacterial activity compared to sodium salts of N-acyl amino acids and standard compounds against Staphylococcus aureus MLS-16 and Bacillus subtilis. These studies revealed that the palmitoyl amino acid surfactants can be exploited in household, skin care formulations, and industrial applications.     

Synthesis,characterization, in vitro antimicrobial and cytotoxic evaluation of Co(II), Ni(II), Cu(II) and Zn(II) complexes derived from bidentate hydrazones

Co(II), Ni(II), Cu(II) and Zn(II) complexes have been synthesized from hydrazone ligands (HL¹–HL⁴) obtained by condensation reaction of 6-chlorothiochroman-4-one with benz hydrazide/nicotinic hydrazide/isonicotinic hydrazide/p-toluic hydrazide. The synthesized compounds (1–20) were characterized by physicochemical procedures, i.e. (FTIR, ¹H NMR, ¹³C NMR, mass, ESR, UV–Vis), TGA/DTA, powder XRD, elemental analysis (CHN), magnetic susceptibility and molar conductance measurements. The various data suggested bidentate nature (NO) of hydrazones, which coordinate with central metal ions via nitrogen of azomethine (–C=N–) group and deprotonated carbonyl oxygen in the enolized form, resulting in octahedral complexes. Low values of molar conductance suggested their non-electrolytic nature. Thermal decomposition pattern of complexes confirms the metal oxides as end product. In vitro antimicrobial activity of hydrazones and their metal complexes were evaluated against two gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus); two gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli); and two fungal strains (Candida albicans and Aspergillus niger) by serial dilution method, and it was found that the metal complexes were highly active as compared to hydrazones. Among all the compounds, complexes 11, 13, 14 and 19 were found most efficient antimicrobial agent. The anticancer activity of (1–20) compounds was performed on human cancer cell lines A549 (lung), DU145 (prostate) and SW620 (colorectal) by MTT assay using paclitaxel as reference drug. The cytotoxicity results suggested compounds [Cu(L²)₂(H₂O)₂] 11 as most potent against A549, DU145 and SW620 cancer cell lines with IC₅₀ values of 3.46, 18.21 and 7.61 µM. Furthermore, compounds (9, 10, 11, 12) were also investigated on A549 cell line for their ROS generation and mitochondrial membrane potential loss and suggested that complex [Cu(L²)₂(H₂O)₂] 11 has highest ROS production and induction of apoptosis by mitochondrial depolarization in cancer cells.

Graphic abstract

The synthesized compounds (1–20) were screened for in vitro cytotoxicity against A549 (lung), DU145 (prostate), SW620 (colorectal) human cancer cell lines. Copper complex (11) was found to be the most active antitumor agent which enhance ROS production and MMP loss on A549 cells.

     

A Dynamic Programming Approach to Determine Optimal Manpower Recruitment Policies

The manpower planning models available in the literature have dealt with how changes take place in a manpower planning system, under various operating and policy constraints. However, none of these models has identified the manpower system costs. In this paper we have identified various manpower system costs. Further, we have developed a manpower planning model with the objective of minimizing the manpower system costs. The model has been found to be analogous to the Wagner-Whitin model in production/inventory management. A numerical example has been given to illustrate the model.     

Synthesis,spectroscopic characterization,biological screening and in vitro cytotoxic studies of 4‐methyl‐3‐thiosemicarbazone derived Schiff bases and their Co (II), Ni (II), Cu (II) and Zn (II) complexes

A series of twenty compounds inclusive of bidentate Schiff bases derived from condensation of 4‐methyl‐3‐thiosemicarbazide with substituted derivatives of napthaldehyde/benzaldehyde/salicylaldehyde and their mononuclear Co (II), Ni (II), Cu (II) and Zn (II) complexes in molar ratio (1:1) were synthesized and characterized. The coordination behavior, modes of bonding and overall geometry of the compounds was known from the elemental analysis, spectral techniques (IR, UV–Vis, ¹H NMR, ¹³C NMR, ESR and ESI‐mass), magnetic moment measurements, molar conductance, thermal and powder XRD studies. The studies revealed octahedral geometry for all the complexes where ligands coordinated in a neutral bidentate manner (NS) via nitrogen atom of azomethine group and sulphur atom of thione group with the metal centre. In vitro biological effects of the compounds were tested against four bacterial species and two fungal strains. The results indicated that the metal complexes showed a marked enhancement in biocidal activity in comparable with the parent Schiff bases. In vitro anticancer activity against the malignant tumor cell lines; human alveolar adenocarcinoma epithelial cell line (A549), human breast adenocarcinoma cell line (MCF7), human prostate cancer cell line (DU145) and human normal lung cell line (MRC‐5) using MTT assay, exposed compound 16 as a leading member with lowest IC₅₀ value of 10.6 ± 0.14 μM against (A549) cell line.     

Isomannide monoundecenoate-based 1,2,3-triazoles: Design,synthesis, and in vitro bioactive evaluation

A new series of isomannide monoundecenoate-based 1,2,3-triazole analogs 6a–e were designed by employing click chemistry in good yields. in vitro bioactive assay manifested that the several target compounds exhibited promising antibacterial and antifungal activities. Notably, compounds having phenyl substituted triazole 6a , and hydroxy phenyl substituted triazole 6b possessed highly selective promising inhibition towards Gram-positive bacterial strains namely Bacillus subtilis and Staphylococcus aureus with MIC value of 3.9 μg/mL. Further, these potential hybrids ( 6a and 6b) also exhibited highly impressive antifungal activity against the tested panel of Candida strains with MIC value of 3.9 μg/mL. Based on our in vitro preliminary antimicrobial study, these two compounds 6a and 6b have been identified as potential antimicrobial lead compounds. Moreover, all prepared derivatives were also evaluated for their in vitro cytotoxic activities against A549, MCF7, DU145 and HeLa cancer cell lines. The results indicated that only the hydroxy phenyl substituted triazole analog 6b displayed good cytotoxic activity towards all tested human cancer cell lines without any significant effects on normal cell line (HUVEC).     

Synthesis of novel triazolothione,thiadiazole, triazole-functionalized furo/thieno[2,3-b]pyridine derivatives and their antimicrobial activity

A series of novel triazolothione, thiadiazole, triazole-functionalized furo/thieno[2,3-b]pyridine derivatives 9a–l, respectively, were prepared starting from 2 (1H) pyridone 3 through selective O/S-alkylation followed by Thorpe–Ziegler cyclization to form furo/thieno[2,3-b]pyridine derivatives 6. Compounds 6 on reaction with hydrazine hydrate resulted carbohydrazide derivatives 7 and further reacted with diverse substituted phenyl isothiocyanates to form phenyl hydrazine carbothiamide derivatives 8. Each compound 8 is independently reacted in presence of NaOH, H₂SO₄, and N₂H₄.H₂O to form triazolothione, thiadiazole, triazole-functionalized furo/thieno[2,3-b]pyridine derivatives 9a–l, respectively. All the products 9a–l were screened against Gram +ve, Gram –ve bacteria and fungal strains. Compounds 9c–h showed high activity against Bacillus subtilis microbial-type culture collection (MTCC) 121 at <8.0 micromolar concentration. Promising compounds further screened for minimum bactericidal concentration against B. subtilis MTCC 121 using ciprofloxacin as standard and found to show very good activity. These compounds also screened for biofilm inhibition activity against B. subtilis MTCC 121 using erythromycin as standard and confirmed the high activity.     

Stress evolution with concentration-dependent compositional expansion in a silicon lithium-ion battery anode particle

Journal of Solid State Electrochemistry - Silicon with the highest known theoretical capacity for lithium uptake may expand in volume by as much as 400%, leading to pulverization and capacity...