H etero-Diels-Alder Reaction, a,/?-Unsaturated Ketones, Styrenes Cycloadditions of 3-aryl-2-benzoyl-2-propenenitriles la,b to styrene (2a) and its methylor methoxy-substituted derivatives 2b-d proceed regioand diastereoselectively yielding cis and trans diastereoisomers of 2,4,6-triaryl-3,4-dihydro-2//-pyran-5-carbonitriles 3 and 4 in 59-72% yield. Cycloadducts cis-3 were the major products. Re...

σRs have been mischaracterized [2-4] and were initially thought to be opioid receptor subtypes [5]. They have been classified into two subtypes based on specific radioligand binding assays using [3H](+)pentazocine for σ1Rs and [3H]1,3-di-o-tolylguanidine ([3H]DTG), in the presence of (+)-pentazocine to mask the σ1R, for σ2Rs [6-11] (Table 1). The σ1R has already been cloned and is a 25-29 kDa i...

N-methyl-D-aspartate (NMDA) receptor blockade in rodents induces behavioural and neurochemical changes reminiscent of schizophrenia symptoms and pathology. To examine how NMDA receptor blockade affects glutamatergic and GABAergic pathways when administered during early brain development, [3H]MK-801 and [3H]muscimol binding to NMDA and GABA(A) receptors was examined at four time-points following...

ABSTRACT A series of novel 1,2,4-thiadiazine 1,1-dioxides were synthesized by condensation of 2-chlorobenzenesulfonamide and 4-chloropyridine-3-sulfonamide with heterocyclic methyl carbimidates obtained from heterocyclic carbonitriles and used at the time of their creation. Substituted amidines were isolated as the intermediates in the reaction with 2-chlorobenzenesulfonamide. Those intermediat...

In vitro antimicrobial activity of seventeen heterocyclic nitrogen compounds {2-substituted pyrido [1,2-a] pyrimidin -4-oxo-1 [4]-3-Carbonitriles and ethyl 5-amino-3-(substituted) - pyrazole-3-Carboxylates} was tested against Escherichia coli, Bacillus subtilis and candida albicans strains, Antimicrobial activity was measured using standard two -fold serial dilution method and the minimum inhib...

We have previously demonstrated the developmental increase of the activity of 11 P-hydroxysteroid dehydrogenase (11 PHSD) in the rat ileum which correlated with the developmental surge of plasma concentrations of corticosteroids, thyroid hormones and insulin. To ascertain whether these hormones directly stimulate 1lPHSD activity we used explant cultures of ileum and distal colon. The intestinal...

A series of 3-arylidene-5-(substituted phenyl)-2(3H)-furanones (3-10) and their nitrogen analogues, 3-arylidene-5-(substituted phenyl)-1-benzyl-2(3H)-pyrrolone (11-14), and 3-arylidene-5-(substituted phenyl)-2(3H)-pyrrolones (15-21) were synthesized. All the compounds were screened for their antimycobacterial activity in vitro against Mycobacterium tuberculosis H37Rv (ATCC 27294) in BACTEC medi...

The transport of highly purified 3H-labelled unconjugated bilirubin (UCB) was investigated in rat liver plasma membrane vesicles enriched in the canalicular domain and found to be stimulated (more than 5-fold) by the addition of ATP. Other nucleotides, such as AMP, ADP, GTP and a non-hydrolysable ATP analogue (adenosine 5'-[alpha, beta-methylene] triphosphate), did not stimulate [3H]UCB transpo...

To identify critical amino acids within the central conserved region of recombinant human cAMP-specific phosphodiesterase 4 subtype A (rhPDE4A), we engineered the expression of point mutants in a fully active rhPDE4A/Met201-886. When histidine residues at positions 433, 437, 473, and 477, which are highly conserved among all PDE families, were changed independently to serine residues, cAMP hydr...

We have isolated variants of L1210 cells (L1210B) expressing, in addition to the "classical" high affinity/low capacity system for reduced folate uptake, high levels of a membrane-associated folate binding protein. This folate binding protein was expressed in L1210 cells grown at low physiological folate levels (less than 0.5 nM), but down-regulated after transfer in standard high folate (2 mic...