No abstract

To further investigate SAR in the class of azecine-type dopamine receptor antagonists, we synthesized a series of derivatives, substituted at the indole-NH of the lead compound LE300 by different alkyl chains in addition to phenylpropyl, allyl, propargyl, and acetyl residues. The affinities of the target compounds for all human dopamine receptors (D(1) -D(5) ) were investigated by radioligand binding assay and their functionality by a calcium assay. Both the affinities and selectivities for the dopamine receptors were found to be affected by the nature of the substituent. The N14-methylated derivative displayed the highest affinities for all D-receptors. In general, the affinities decreased with increasing chain length of the N-alkyl. Different substituents, partly led to altered affinity, and selectivity profile when compared with our lead LE300.

Antibiotic‐resistant bacteria continue to play an important role in human health and disease. Inventive strategies are necessary to develop new therapeutic leads to challenge drug‐resistance problems. From this perception, new quinoline hybrids bearing bioactive pharmacophores were synthesized. The newly synthesized compounds were evaluated for their in vitro antibacterial activity against nine bacterial pathogenic strains. The results revealed that most compounds exhibited good antibacterial activities. Seven compounds (2b, 3b, 4, 6, 8b, and 9c,d) displayed enhanced activity against methicillin‐resistant Staphylococcus aureus compared to ampicillin. These compounds were subjected to an in vitro S. aureus DNA gyrase ATPase inhibition study, which revealed that compounds 8b, 9c, and 9d showed the highest inhibitory activity with IC50 values of 1.89, 2.73, and 2.14 μM, respectively, comparable to novobiocin (IC50, 1.636 μM). Compounds 2a–c, 3a, 7c, 9c,d, and 10a,b revealed half the potency of levofloxacin in inhibiting the growth of Pseudomonas aeruginosa. As an attempt to rationalize the observed antibacterial activity for the most active compounds 8b, 9c, and 9d, molecular docking in the ATP binding site of S. aureus gyrase B was performed using Glide. Such compounds could be considered as promising scaffolds for the development of new potent antibacterial agents.

A new series of p-benzoquinones, hydroquinones, and quinol dimethyl ethers substituted by a pyrazole ring either directly or after an oxoethyl linker was synthesized and screened for in vitro cytotoxic activity. Compounds 8d, f, g, i, and 9c, f, and 13c exhibited broad-spectrum activity (GI 50 MG-MID values 9.27-14.72 mM). With regard to sensitivity, compounds 8f and 9c, f have proved to possess a remarkable activity against leukemia tumor cell lines (GI 50 = 3.43-5.03 mM). Indeed, compound 13c showed the highest activity profile against individual leukemia subpanel cell line SR (GI 50 = 0.91 mM).

ChemInform Abstract The preparation of title compounds such as (IV) (14 examples) and (V) (12 examples) is described. Some of them possess antimicrobial activity against Staphylococcus aureus and Escherichia coli, but not against Candida albicans.