Synthesis and evaluation of antitumoral activity of ester and amide derivatives of 2-arylamino-6-trifluoromethyl-3-pyridinecarboxylic acids.

The synthesis and antitumoral activity of ester and amide derivatives of 2-arylamino-6-trifluoromethyl-3-pyridinecarboxylic acids 8-58 is described. Trifluoromethylpyridine derivatives 8-58 were evaluated for their anticancer activity toward human tumoral cell lines by the National Cancer Institute (NCI). Most of them possess encouraging anticancer activity, having GI(50) values in the low micromolar to nanomolar concentration range.

Synthesis and in vitro antitumoral activity of new 3,5-dicyanopyridine derivatives.

A new series of 2-amino-4-aryl-6-dialkylamino-3,5-dicyanopyridines, 20-47, were synthesized in satisfactory overall yield, through a simple synthetic strategy using 3-amino-3-(dialkylamino)-propenenitriles 1 and 2 as key intermediates. 3,5-Dicyanopyridine derivatives 20-47 were evaluated for their in vitro anticancer activity toward cell lines of nine different types of human cancers. Some of the newly prepared compounds demonstrated inhibitory effects on the growth of a wide range of cancer cell lines generally at 10(-6) M level and in some cases at 10(-8) M concentration.

Amidrazones as precursors of biologically active compounds--synthesis of diaminopyrazoles for evaluation of anticancer activity.

The regioselectivity of coupling phenyl isocyanate to 3-(2-acylhydrazino)-3-aminopropenenitriles and ethyl 3-(2-acylhydrazino)-3-aminopropenoates as simple access to aminopyrazole derivatives, endowed with potential antitumoral activity, is reported. 3-(2-Acylhydrazino)-3-aminopropenenitriles react with phenyl isocyanate to afford 3-amino-3-(2-acylhydrazino)-2-phenylaminocarbonyl-2-propenenitriles. These key intermediates were cyclized into 3,5-diaminopyrazole-4-carboxamide derivatives.

New potential anticancer agents based on the anthranilic acid scaffold: synthesis and evaluation of biological activity.

The synthesis and anticancer activity of new compounds designed on the anthranilic acid scaffold are reported. The antiproliferative activity was assayed by the National Cancer Institute in established in vitro and in vivo anticancer experimental models. Structural variations based on the flufenamic acid motif afforded a series of (hetero)aryl esters of N-(2-(trifluoromethyl)pyridin-4-yl)anthranilic acid, which showed in vitro growth inhibitory properties against human tumor cell lines in nanomolar to low micromolar concentrations.

Synthesis and in vitro antitumoral activity of new hydrazinopyrimidine-5-carbonitrile derivatives.

A new series of 2-amino-6-(2-alkyl or arylidenehydrazinyl)-4-(dialkylamino)pyrimidine-5-carbonitriles, 5-24, were synthesized in satisfactory overall yield, using 2-amino-4-(dialkylamino)-6-hydrazino-5-pyrimidinecarbonitriles 3, 4, as key intermediates, by applying classical synthetic methods to construct the hydrazone moiety at C-6 of the pyrimidine ring. Hydrazinopyrimidine derivatives 5-24 were evaluated for their in vitro anticancer activity toward cell lines of nine different types of human cancers. Some of the newly prepared compounds demonstrated inhibitory effects on the growth of a wide range of cancer cell lines generally at 10(-5)M level and in some cases at 10(-7)M concentrations.

Synthesis and antiproliferative activity of 2,6-dibenzylamino-3,5-dicyanopyridines on human cancer cell lines.

A new series of 2,6-dibenzylamino-3,5-dicyanopyridines were synthesized and evaluated for their in vitro anticancer activity toward cell lines of nine different types of human cancer. Some of newly prepared compounds demonstrated remarkable anticancer activity against most of the tested subpanel tumor cell lines.

Synthesis of new N-(2-(trifluoromethyl)pyridin-4-yl)anthranilic acid derivatives and their evaluation as anticancer agents.

The N-(2-(trifluoromethyl)pyridin-4-yl)anthranilic acid 6 and a series of its ester and amide derivatives were synthesized and evaluated for their in vitro cytotoxic activity against human cancer cells. Ester derivatives 13 and 18 exhibited potent growth inhibitory activity with GI(50) values at nanomolar concentrations. Among amide derivatives, N-anthraniloylglycinate 19 shown moderate inhibitory activity in the full panel cancer cell line screening.

Ontogeny of kainate receptor gene expression in the developing rat midbrain and striatum.

Kainate (KA) receptors are a family of ionotropic glutamate receptors, which mediate the excitatory synaptic transmission in various areas of the mammalian CNS. We have studied the expression pattern of the genes encoding for KA receptor subunits (Glur5-1, Glur5-2, Glur6, Glur7, KA1 and KA2) in rat prenatal (E), postnatal and adult ventral mesencephalon (MES) and striatum (STR) and in fetal midbrain primary cultures. Each receptor subunit shows a unique area- and temporal-expression pattern.

6R-Tetrahydrobiopterin induces dopamine synthesis in a human neuroblastoma cell line, LA-N-1. A cellular model of DOPA-responsive dystonia.

Dopa-responsive dystonia (DRD) is an extrapyramidal disorder caused by deficit of 5,6,7,8-tetrahydrobiopterin (BH4), cofactor for tyrosine hydroxylase (TH). In these patients the nigrostriatal dopaminergic neurons normally express TH and the cellular machinery for the dopamine uptake. LA-N-1 is a human neuroblastoma cell line expressing tyrosine hydroxylase.

Ontogeny of AMPA receptor gene expression in the developing rat midbrain and striatum.

AMPA receptors mediate most of the fast excitatory synaptic transmission in the mammalian CNS. Their ontogeny during embryonic (E) and postnatal (P) development is still poorly understood. We have studied the expression of the genes encoding for AMPA glutamate receptor subunits (GlurA, GlurB, GlurC and GlurD) in the rat ventral mesencephalon (MES) and striatum (STR) and in fetal midbrain primary cultures.

Haloperidol does not produce dopamine cell depolarization-block in paralyzed, unanesthetized rats.

A widely accepted theory postulates that chronic treatment with neuroleptics causes, in rats, the depolarization block of the majority of midbrain dopamine (DA) neurons. However, we reported that such treatment fails to reduce the number of spontaneously active DA neurons when the neuronal sampling is performed in the d-tubocurarine-paralyzed instead of chloral-hydrate anesthetized preparation. The present experiments were aimed at verifying whether the negative results might be due to the use of d-tubocurarine as paralyzing agent.

Spontaneous bursting activity of dopaminergic neurons in midbrain slices from immature rats: role of N-methyl-D-aspartate receptors.

Dopamine neurons in midbrain coronal slices from adult rats (40-70 days old) discharged only in pacemaker-like mode. Irregular or bursting mode was never observed. In contrast, dopamine neurons in slices from immature rats (15-21 days old) exhibited not only pacemaker-like firing (53.

Depolarization inactivation of dopamine neurons: an artifact?

A widely accepted theory postulates that, in rats, chronic treatment with neuroleptics causes the depolarization inactivation of the majority of midbrain dopamine (DA) neurons. The present study was aimed to verify whether general anesthesia and/or other factors might contribute to the depolarization inactivation of A9 and A10 DA neurons. To investigate on the possible role played by DA receptor subtypes, three representatives DA antagonists were used: haloperidol (a mixed D1/D2), (-)-sulpiride (a selective D2) and SCH 23390 (a selective D1).

Failure of chronic haloperidol to induce depolarization inactivation of dopamine neurons in unanesthetized rats.

Chronic treatment with neuroleptics has been reported to induce a status of depolarization inactivation of the majority of midbrain dopamine neurons. The present study was aimed at determining whether general anesthesia might be a contributory cause of depolarization inactivation of substantia nigra dopamine neurons. In agreement with previous studies, where neuronal sampling was carried out in animals under chloral hydrate anesthesia, chronic treatment with haloperidol (0.