Synthesis and dopaminergic activity of some halogenated mono- and dihydroxylated 2-aminotetralins

Conformational mimetics of the α-methyl chalcone TUB091 binding tubulin: Design, synthesis and antiproliferative activity

Based on the conformation of the α-methyl chalcone TUB091 in its complex with tubulin, a series of conformational mimetics have been designed and synthesized where the methyl group of the chalcone has been fused to phenyl ring B resulting in 1,2,3,4-tetrahydronaphthalen-2-yl aryl ketones. Among the synthesized compounds, the 5-amino-6-methoxy derivative, with a similar substitution pattern to that of TUB091, showed antiproliferative activity around 20 nM against tumor and endothelial cells. Tubulin binding experiments confirmed its binding to tubulin at the colchicine site with a Kb of 2.4 × 10⁶ M^-1 resulting in the inhibition of the in vitro assembly of purified tubulin. Moreover, based on the recently reported complex of combretastatin A4 (CA4) with tubulin, a comparative analysis of the binding mode of CA4 and the α-methyl chalcone to tubulin has been performed.

Design and synthesis of a new series of highly potent RAF kinase-inhibiting triarylpyrazole derivatives possessing antiproliferative activity against melanoma cells

BACKGROUND

Inhibition of V600E-B-RAF kinase represents a potential avenue for melanoma treatment. Herein, a series of 1,3,4-triarylpyrazoles possessing amide linker were designed, synthesized and evaluated for RAF kinase inhibition.

RESULTS

Compounds 1d and 1f were more potent than sorafenib against A375 cell line, and their selectivity indexes toward A375 than HS27 fibroblasts were 25.43 and 45.83, respectively. Compound 1f was more potent against the melanoma cell lines with B-RAF V600E mutation than melanoma cells with NRAS mutation and normal skin epithelial cells. Compounds 1d and 1f showed strong potency and selectivity against V600E-B-RAF kinase with IC₅₀ values of 3.80 and 2.98 nM, respectively. Molecular docking studies revealed their binding mode.

CONCLUSION

Potent and selective V600E-B-RAF antimelanoma agents were discovered. [Formula: see text].

Design, synthesis, and in vitro antiproliferative and kinase inhibitory effects of pyrimidinylpyrazole derivatives terminating with arylsulfonamido or cyclic sulfamide substituents

A novel series of substituted pyrimidine compounds bearing N-phenylpyrazole and terminating with aryl and cyclic sulfonamido moiety were designed, synthesized, and evaluated in vitro as antiproliferative agents against a panel of 53 cell lines of different tissues at the NCI. Among them, compound 1d with p-chlorobenzenesulfonamido terminal moiety, ethylene spacer, and 4-chloro-3-methoxyphenyl ring at position 3 of the pyrazole nucleus showed the highest mean percentage inhibition value over the whole cancer cell line panel at 10 μM concentration. It showed broad-spectrum antiproliferative activity over many cell lines of different cancer types. For instance, compound 1d inhibited the growth of HL-60 (TB), SR leukemia, and T-47D and MCF-7 breast cancer cell line by 135.92%, 119.44%, 95.32%, and 82.03% at 10 μM, respectively. And it inhibited the growth of COLO 205 colon, HT29 colon, BT-549 breast, and ACHN renal cancer cell lines by more than 80% at the same test concentration. However, testing compound 1d upon determining its IC₅₀ against the most sensitive cell lines showed to good extent selectivity against HT29 colon cancer cell line than HL-60 leukemia and MRC-5 lung fibroblasts (normal cells). Compound 1d was further tested against 12 kinases of different kinase families, and the highest inhibitory effect was exerted against RAF1, V600E-B-RAF, and V600K-B-RAF kinases.

New triarylpyrazoles as broad-spectrum anticancer agents: design, synthesis, and biological evaluation

A new series of diarylureas and diarylamides possessing 1,3,4-triarylpyrazole scaffold was designed and synthesized. Their in vitro antiproliferative activities against NCI-60 cell line panel were tested. Most of the compounds showed strong and broad-spectrum antiproliferative activities. Compound 18 exerted sub-micromolar IC50 values over all the subpanels of nine different cancer types. Its IC50 value over MDA-MB-435 melanoma cell line was 27 nM. Compounds 10-13, 22, and 23 possessing urea spacer exerted lethal effect over the NCI-60 panel with mean %inhibitions more than 100% in single-dose testing. Compounds 13 and 23 with urea linker and 3',5'-bis(trifluoromethyl)phenyl terminal ring showed the highest mean %inhibition over the NCI-60 panel in single-dose testing, and showed high potencies and broad-spectrum anticancer activities in five-dose testing.

Design, synthesis, and antiproliferative activity of 3,4-diarylpyrazole-1-carboxamide derivatives against melanoma cell line

Synthesis of a new series of 3,4-diarylpyrazole-1-carboxamide derivatives is described. Their antiproliferative activity against A375P human melanoma cell line was tested and the effect of substituents on the diarylpyrazole scaffold was investigated. The biological results indicated that five synthesized compounds (Ig, Ii, IIc, IIg, and IIh) exhibited similar activity to Sorafenib. In addition, three compounds (IIa, IIb, and IIi) were more potent than Sorafenib. Among all of these derivatives, compound IIa which has dimethylamino and phenolic moieties showed the most potent antiproliferative activity against A375P human melanoma cell line. Virtual screening was carried out through docking of the most potent compound IIa into the domain of V600E-b-Raf and the binding mode was studied.

Nucleophilic deoxyfluorination of catechols

Nucleophilic deoxyfluorinaiton of one of the two hydroxyl groups of catechols has been developed via the Umpolung concept. This method was successively applied to naturally occurring catechols, such as catechins and dopamine, to produce novel fluorinated analogues.

Interaction of lipopolysaccharide endotoxin produced from Escherichia coli with D-tubocurarine at the nicotinic2 receptor and adenosine 3':5' cyclic monophosphate during physiological contraction in skeletal muscle

In this report the murine model of endotoxicosis was used to evaluate hyposensitivity to the neuromuscular relaxant D-tubocurarine (dTC). This hyposensitivity was expressed in terms of a decreased potency to dTC. A rightward shift of the dose-response curve due to endotoxin was observed. Mice were subjected to cumulative intraperitoneal doses of Escherichia coli endotoxin over a 2-wk period. The interaction between endotoxin and dTC was examined during an acute (1 wk) and chronic (2 wk) period of endotoxicosis. Muscle twitch analyses were performed and samples of gastrocnemius muscle were assayed for adenosine 3':5' cyclic monophosphate (cAMP) by [125I]radioimmunoassay. A parallel shift in the dose-response curve occurred in the endotoxin group subjected to doses corresponding to one-third the dose evoking 50% lethality for 2 wk. Both skeletal muscle tension and cAMP levels decreased as cumulative endotoxin doses increased. A relationship between decreasing cAMP levels and increasing dTC and effective dose required to achieve 50% muscle paralysis values was thought to be evoked by the agonistic activity of E. coli endotoxin leading to desensitizing of adenylate cyclase. The perturbations of the classical second messenger cAMP system by endotoxin may be responsible for skeletal muscle dysfunction observed in immunocompromised patients.

New putative selective agonists at the D-1 dopamine receptor: behavioural and neurochemical comparison of CY 208-243 with SK&F 101384 and SK&F 103243

Three putative D-1 agonists with nonbenzazepine structures were compared with the prototype benzazepine D-1 partial agonist SK&F 38393 for their behavioural effects in the intact adult rat, and for their relative affinities for D-1 and D-2 dopamine receptors in vitro. SK&F 103243, a restricted conformation analogue of SK&F 38393, and SK&F 101384 (8-Cl-ADTN) showed low affinity for D-1 and D-2 receptors in in vitro binding studies, and failed to induce any behavioural effects on peripheral administration. CY 208-243, an indolophenanthridine derivative, showed appreciable affinity not only for D-1 receptors but also for D-2 receptors, while in behavioural studies it showed some of the characteristics of a partial D-1 dopamine receptor agonist; thus, it failed to promote stereotyped behaviour, but induced episodes of intense grooming which were sensitive to blockade by the D-1 antagonist SCH 23390. No such effect was induced by the selective D-2 agonist RU 24213. CY 208-243 is the first nonbenzazepine which shows some of the properties of a D-1 agonist in the intact adult animal. However, the differences between its in vitro binding characteristics and its functional properties remain enigmatic.