Evaluation of blood-brain barrier passage of a muscarine M1 agonist and a series of analogous tetrahydropyridines measured by in vivo microdialysis

Insilico studies of organosulfur-functional active compounds in garlic

Garlic has been used medicinally since antiquity because of its antimicrobial activity, anticancer activity, antioxidant activity, ability to reduce cardiovascular diseases, improving immune functions, and antidiabetic activities and also in reducing cardiovascular diseases and improving immune functions. Recent studies identify that the wide variety of medicinal functions are attributed to the sulfur compounds present in garlic. Epidemiological observations and laboratory studies in animal models have also showed anticarcinogenic potential of organosulfur compounds of garlic. In this study, in silico analysis of organosulfur compounds is reported using the methods of theoretical chemistry to elucidate the molecular properties of garlic as it is more time and cost efficient, reduces the number of wet experiments, and offers the possibility of replacing some animal tests with suitable in silico models. The analysis of molecular descriptors defined by Lipinski has been done. The solubility of drug in water has been determined as it is of useful importance in the process of drug discovery from molecular design to pharmaceutical formulation and biopharmacy. All toxicities associated with candidate drug have been calculated. P-Glycoprotein expressed in normal tissues as a cause of drug pharmacokinetics and pharmacodynamics has been examined. Drug-plasma protein binding and volume of distribution have also been calculated. To avoid rejection of drugs, it is becoming more important to determine pK(a), absorption, polar surface area, and other physiochemical properties associated with a drug, before synthetic work is undertaken. The present in silico study is aimed at examining these compounds of garlic to evaluate its possible efficacy and toxicity under conditions of actual use in humans.

Synthesis of Substituted N-[4(5-Methyl/phenyl-1,3,4-oxadiazol-2-yl)-3,6-dihydropyridin-1(2H)-yl]benzamide/benzene Sulfonamides as Anti-Inflammatory and Anti-Cancer Agents

Fourteen novel substituted N-[4(5-methyl/phenyl-1,3,4-oxadiazol-2-yl)-3,6-dihydropyridin-1(2H)-y1] benzamide/benzene sulfonamides (11a-n) were synthesized in fair to good yields via sodium borohydride reduction of the corresponding substituted N-(benzoylimino)-4-(5-methyl/5-phenyl-1,3,4-oxadiazol-2yl) pyridinium ylide (10a-n) in absolute ethanol.

N-Oxide analogs of WAY-100635: new high affinity 5-HT1A receptor antagonists

WAY-100635 [N-(2-(1-(4-(2-methoxyphenyl)piperazinyl)ethyl))-N-(2-pyridinyl)cyclohexanecarboxamide] 1 and its O-desmethyl derivative DWAY 2 are well-known high affinity 5-HT(1A) receptor antagonists, which when labeled with carbon-11 (beta+; t(1/2) = 20.4 min) in the carbonyl group are effective radioligands for imaging brain 5-HT(1A) receptors with positron emission tomography (PET). In a search for new 5-HT(1A) antagonists with different pharmacokinetic and metabolic properties, the pyridinyl N-oxide moiety was incorporated into analogs of 1 and 2. NOWAY 3, in which the pyridinyl ring of 1 was oxidized to the pyridinyl N-oxide, was prepared via nucleophilic substitution of 2-[4-(2-methoxyphenyl)piperazin-1-yl]ethylamine on 2-chloropyridine-N-oxide followed by acylation with cyclohexanecarbonyl chloride. 6Cl-NOWAY 4, a more lipophilic (pyridinyl-6)-chloro derivative of 3, was prepared by treating 1-(2-methoxyphenyl)-4-(2-(2-(6-bromo)aminopyridinyl-N-oxide)ethyl)piperazine with cyclohexanecarbonyl chloride for acylation and concomitant chloro for bromo substitution. NEWWAY 5, in which the 2-hydroxy-phenyl group of 2 is replaced with a 2-pyridinyl N-oxide group with the intention of mimicking the topology of 2, was prepared in five steps from 2-(chloroacetylamino)pyridine. N-Oxides 3-5 were found to be high affinity antagonists at 5-HT(1A) receptors, with 3 having the highest affinity and a Ki value (0.22 nM) comparable to that of 1 (0.17 nM). By calculation the lipophilicity of 3 (LogP = 1.87) is lower than that of 1 by 1.25 LogP units while TLC and reverse phase HPLC indicate that 3 has slightly lower lipophilicity than 1. On the basis of these encouraging findings, the N-oxide 3 was selected for labeling with carbon-11 in its carbonyl group and for evaluation as a radioligand with PET. After intravenous injection of [carbonyl-11C]3 into cynomolgus monkey there was very low uptake of radioactivity into brain and no PET image of brain 5-HT(1A) receptors was obtained. Either 3 inadequately penetrates the blood-brain barrier or it is excluded from brain by an active efflux mechanism. Rapid deacylation of 3 was not apparent in vivo; in cynomolgus monkey plasma radioactive metabolites of [carbonyl-11C]3 appeared less rapidly than from the radioligands [carbonyl-11C]1 and [carbonyl-11C]2, which are known to be primarily metabolized by deacylation. Ligand 3 may have value as a new pharmacological tool, but not as a radioligand for brain imaging.

A review of membrane sampling from biological tissues with applications in pharmacokinetics, metabolism and pharmacodynamics

This review provides an overview of membrane sampling techniques, microdialysis and ultrafiltration, and cites illustrations of their applications in pharmacokinetics, metabolism and/or pharmacodynamics. The review organizes applications by target tissue and general type of information gleaned. It focuses on recently published microdialysis studies (1999 to this writing) and offers the first review of ultrafiltration sampling studies. The advantages and limitations of using microdialysis and ultrafiltration sampling as tools for obtaining pharmacokinetic and metabolism data are discussed. Numerous examples are described including studies in which several types of data are collected simultaneously. Reports that study local metabolism of drug delivered through the probe are also presented.