Cytotoxic and apoptotic effects of synthetic benzochromene derivatives on human cancer cell lines.

With the aim of discovering potential cytotoxic agents, a series of benzochromene derivatives were screened for their cytotoxic activity against seven human cancer cell lines by standard 3-(4, 5-dimethyl thiazol)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptosis, as the mechanism of cell death, was investigated morphologically by acridine orange/ethidium bromide staining and cell surface expression assay of phosphatidylserine by Annexin V-PE/7-AAD technique. The effects of compounds on reactive oxygen species (ROS) and nitric oxide (NO) generations in three human breast cancer cell lines were also studied. All compounds showed significant cytotoxic activity with inhibitory concentration (IC50) values in the micromolar range (4.6-21.5 µM). The results of apoptosis evaluation suggested that the cytotoxic activity of these compounds in breast cancer cells occurs via apoptosis. MCF-7 cell line showed higher levels of ROS and NO production after treatment with compounds. The increase in ROS production after 4 and 24 h indicated that one of the ways that these compounds can induce apoptosis is by increasing ROS generation. Cytotoxic and apoptotic effects of these compounds in human cancer cells indicated that they can be a good candidate for further pharmacological studies to discover effective anticancer agents.

Ab initio DFT study of bisphosphonate derivatives as a drug for inhibition of cancer: NMR and NQR parameters.

DFT computations were carried out to characterize the (17)Oand (2)H electric field gradient, EFG, in various bisphosphonate derivatives. The computations were performed at the B3LYP level with 6-311++G (d,P) standard basis set. Calculated EFG tensors were used to determine the (17)O and (2)H nuclear quadrupole coupling constant, χ and asymmetry parameter, η. For better understanding of the bonding and electronic structure of bisphosphonates, isotropic and anisotropic NMR chemical shieldings were calculated for the (13)C, (17)O and (31)P nuclei using GIAO method for the optimized structure of intermediate bisphosphonates at B3LYP level of theory using 6-311++G (d, p) basis set. The results showed that various substituents have a strong effect on the nuclear quadrupole resonance (NQR) parameters (χ, η) of (17)O in contrast with (2)H NQR parameters. The NMR and NQR parameters were studied in order to find the correlation between electronic structure and the activity of the desired bisphosphonates. In addition, the effect of substitutions on the bisphosphonates polarity was investigated. Molecular polarity was determined via the DFT calculated dipole moment vectors and the results showed that substitution of bromine atom on the ring would increase the activity of bisphosphonates.

An efficient, multicomponent approach for solvent-free synthesis of 2-amino-4H-chromene scaffold.

Solvent-free one-pot synthesis of 2-amino-4H-chromene scaffold is described in a very simple, efficient, and environmentally benign method using sodium carbonate as a cheap and non-toxic catalyst with up to excellent yields.

Mechanochemical solvent-free and catalyst-free one-pot synthesis of pyrano[2,3-d]pyrimidine-2,4(1H,3H)-diones with quantitative yields.

Solvent-free synthesis of pyrano[2,3-d]pyrimidine-2,4(1H,3H)-diones by ball-milling and without any catalyst is described. This method provides several advantages such as being environmentally friendly, using a simple workup procedure, and affording high yields.