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Repression of target genes by the transcriptional repressor neuronal restrictive silencing factor (NRSF)/repressor element 1 silencing transcription factor (REST) contributes to enduring plasticity in the developing brain. However, the cofactor(s) interacting with NRSF to enable target gene repressor are not well understood, and may vary among neuronal populations and brain regions as well as with different contexts. Here we employed the novel designer drug mS-11 to block the interactions of the cofactor Sin3 with NRSF. We tested if NRSF-Sin3 interaction is required for repression of NRSF target genes in developing hypothalamus after activity-dependent modulation of NRSF function. In the hypothalamus in vitro, blocking glutamatergic neurotransmission robustly increased NRSF binding to the target gene Crh, resulting in its repression. Blocking the binding of NRSF to the chromatin with decoy NRSE-oligodeoxynucleotides abrogated this repression. In contrast, mS-11 at several concentrations did not impede Crh repression. NRSF-mediated repression may underlie disease processes such as the onset of epilepsy. Therefore, identifying small-molecule antagonists of NRSF is crucial for the development of disease-preventing or modifying interventions.

The anaphylatoxin C5a is a potent chemotactic factor for neutrophils and other leukocytes, and functions as an important inflammatory mediator. Through a high capacity screening followed by chemical optimization, we identified a novel non-peptide C5a receptor antagonist, N-[(4-dimethylaminophenyl)methyl]-N-(4-isopropylphenyl)-7-methoxy-1,2,3,4-tetrahydronaphthalen-1- carboxamide hydrochloride (W-54011). W-54011 inhibited the binding of (125)I-labeled C5a to human neutrophils with a K(i) value of 2.2 nm. W-54011 also inhibited C5a-induced intracellular Ca(2+) mobilization, chemotaxis, and generation of reactive super oxide species in human neutrophils with IC(50) values of 3.1, 2.7, and 1.6 nm, respectively. In C5a-induced intracellular Ca(2+) mobilization assay with human neutrophils, W-54011 did not show agonistic activity at up to 10 microm and shifted rightward the concentration-response curves to C5a without depressing the maximal responses. Examination on the species specificity of W-54011 revealed that it was able to inhibit C5a-induced intracellular Ca(2+) mobilization in neutrophils of cynomolgus monkeys and gerbils but not mice, rats, guinea pigs, rabbits, and dogs. In gerbils, oral administration of W-54011 (3-30 mg/kg) inhibited C5a-induced neutropenia in a dose-dependent manner. The present report is the first description of an orally active non-peptide C5a receptor antagonist that could contribute to the treatment of inflammatory diseases mediated by C5a.

When treated with concentrated nitric acid in dichloromethane at room temperature, the title compounds undergo an exclusive attack on the methyl group at the most crowded site, giving 6-acyl-2,3,4,5-tetramethylbenzyl nitrates, and 2,6-diacyl-3,4,5-trimethylbenzyl nitrates and/or (2,6-diacyl-3,4,5-trimethylphenyl)nitromethanes respectively, as the major products. While the predominant mode of the side-chain substitution reactions is nitrooxylation for acylpentamethylbenzenes and 1,3-dipivaloyl-2,4,5,6-tetramethylbenzene, it shifts to nitration for 1,3-bis(trihalogenoacetyl)-2,4,5,6-tetramethylbenzenes. Nitrodeacylation is seen to some extent for pivaloylbenzenes, but not for trihalogenoacetylbenzenes. The exclusive attack on the methyl group at the most hindered position can be explained by a sequence involving the attachment of a nitronium ion at the site meta to the acyl group, followed by a proton release from the resulting arenium ion to form a nitromethylenecyclohexadiene intermediate, which is then t...

Synthesis and antibacterial activities of 7-[2-(2-amino-1,3,4-thiadiazol-5-yl)acetamido]-cephalosporins and their derivatives having the methoxyimino group at the 2-position of the 7-acyl moiety are described. These compounds are of interest as structural analogues of potent antibiotics, 7-[2-(2-aminothiazol-4-yl)acetamido]cephalosporins. 7-[2-(2-Amino-1,3,4-thiadiazol-5-yl)acetamido]cephalosporins showed comparable activity with cefazolin. Introduction of methoxyimino group to the 7-side chain resulted in a lowering of activity.

The reaction of 2,5-dimethylthiophene with copper(II) nitrate in acetic anhydride gave 3-nitro-2,5-dimethyl-thiophene and 2,5-dimethyl-3-(5-methyl-2-thenyl)thiophene as major isolable products. The treatment of 3,4-dibromo-2,5-dimethylthiophene with nitric acid (d=1.5) in dichloromethane in the presence of a catalytic amount of sulfuric acid afforded 3,4-dibromo-5-methyl-2-(nitrooxymethyl)thiophene, which, on thin-layer chromatog-raphy over silica gel using hexane as the eluant, underwent a partial novel coupling reaction through the loss of one methylene carbon atom, thus giving 3,3′,4,4′-tetrabromo-5,5′-dimethyldi-2-thienylmethane along with the expected 3,4-dibromo-2-hydroxymethyl-5-methylthiophene and bis(3,4-dibromo-5-methyl-2-thenyl) ether.

The reaction in acetic acid of hexamethylbenzene and hexamethylbenzene-d18 with nitric acid in the dark has been investigated under various conditions using a high-pressure liquid chromatographic method. Pentamethylbenzyl nitrate, pentamethylphenylnitromethane, pentamethylbenzyl acetate, and pentamethylbenzyl alcohol were formed immediately after the mixing of reactants; their relative amounts remained almost unchanged up to nearly 50% conversion. The addition of sodium nitrite gave little influence on the composition of the product mixture, while urea was found to depress somewhat the formation of nitromethane. In the presence of lithium nitrate, the reaction was modestly accelerated and the nitrate formation seems to be slightly favored over the nitromethane formation. Hexamethylbenzene-d18 reacted with nitric acid at the same rate as the non-labeled hydrocarbon did, but the benzyl nitrate/phenylnitromethane ratio in the product mixture was considerably higher in the former. Based on the quantitative da...

Treatment of 2,6-dibromo-3,4,5-trimethylaniline with t-butyl nitrite in N,N-dimethylformamide at 60–65 °C was found to give a significant amount of a side-chain nitration product, 3,5-dibromo-2,6-dimethylphenylnitromethane, in addition to the expected 4,6-dibromo-1,2,3-trimethylbenzene.

Nitration of 2,5-dimethylthiophene with copper(II) nitrate in acetic anhydride gives 2,5-dimethyl-3-nitrothiophene and 3,2′-methylene (2,5-dimethylthiophene) (5′-methylthiophene) as major products. Treatment of 3,4-dibromo-2,5-dimethylthiophene with nitric acid (d = 1.5) in dichloromethane in the presence of a catalytic amount of sulfuric acid yields 3,4-dibromo-5-methyl-2-nitrooxymethylthiophene as the sole major product.

2,4-Dipivaloyl-1,3,5-trimethylbenzene, 4,6-dipivaloyl-1,2,3,5-tetramethylbenzene, and 3,6-dipivaloyl-1,2,4,5-tetramethylbenzene were prepared by the Friedel-Grafts dipropionylation of the corresponding polymethylbenzenes, followed by the exhaustive methylation of the resulting diketones with potassium t-butoxide and methyl iodide in boiling benzene-t-butyl alcohol. The PMR and IR spectra are reported for these new compounds.

An asymmetrical t-pentyl derivative of Yang’s biradical was prepared, and the g- and D-tensor values of the biradical were determined from an analysis of an asymmetric ESR spectrum of a frozen solution containing the biradical. The result may be understood by assuming that the benzene ring onto which two pentyl groups are substituted is twisted more than the other two benzene rings. On the other hand, the fluid solution ESR spectrum shows seven hyperfine splittings due to six equivalent meta ring protons in the three benzene rings of the pentyl derivative.