Synthesis and structure-activity relationships of M(2)-selective muscarinic receptor ligands in the 1-[4-(4-arylsulfonyl)-phenylmethyl]-4-(4-piperidinyl)-piperazine family

The synthesis and muscarinic binding properties of compounds based on the 1-[4-(4-arylsulfonyl)phenylmethyl]-4-(1-aroyl-4-piperidinyl)-piperazine skeleton are described. For compounds, substituted with appropriately configured methyl groups at the benzylic center and at the piperazine 2-position, high levels of selective, M(2) subtype affinity could be obtained, particularly when the terminal N-aroyl residue was ortho-substituted.     

1-[(Benzofuran-2-yl)phenylmethyl]-triazoles and -tetrazoles - potent competitive inhibitors of aromatase.

The synthesis of a series of novel 1-[(benzofuran-2-yl)phenylmethyl]-triazoles and -tetrazoles is described. The compounds were tested for human placental aromatase inhibition in vitro, using [1beta-3H]-androstenedione as the substrate for the aromatase enzyme, the percentage inhibition and IC50 data is included.     

3-Urea-1-(phenylmethyl)-pyridones as novel, potent, and selective EP3 receptor antagonists

A series of 3-urea-1-(phenylmethyl)-pyridones was discovered as novel EP(3) antagonists via high-throughput screening and subsequent optimization. The synthesis, structure-activity relationships, and optimization of the initial hit that resulted in potent and selective EP(3) receptor antagonists such as 11g are described.     

Synthesis and biological activities of linear and cyclic enkephalin analogues containing a psi (E,CH = CH) or psi (CH2CH2) isosteric replacement.

The peptide CO-NH function was replaced by a trans carbon-carbon double bond or by a CH2-CH2 isostere in enkephalin analogues of DADLE, DCDCE-NH2 or DPDPE. In DADLE the 2-3 and the 3-4 peptide bond was modified, whereas in the cyclic analogues the Gly3-Phe4 bond was replaced by the isosteres Gly psi (E,CH = CH)Phe [5-amino-2-(phenylmethyl)-3(E)-pentenoic acid] or Gly psi (CH2CH2)Phe [5-amino-2-(phenylmethyl)pentanoic acid]. In general, the modification results in a drop in potency which is the largest for the flexible CH2-CH2 replacement. The Gly3 psi (E,CH = CH)Phe4 DCDCE-NH2 analogue retains considerable potency. These results confirm the importance of the peptide function at the 2-3 and 3-4 position in enkephalin analogues for biological potency.     

Chiral synthesis of (2S,3S)-2-(2-morpholin-2-yl-2-phenylmethoxy)phenol

Resolution of (2RS,3RS)-2-[alpha-(2-methoxymethoxyphenoxy)phenylmethyl]morpholine, 11, with (+) mandelic acid led to the formation of (+)-(2S,3S)-2-[alpha-(2-methoxymethoxyphenoxy)phenyl methyl] morpholine (11a). Compound 11 was synthesized in seven steps from (2RS,3RS)-cinnamyl alcohol-2,3-epoxide (4), with an overall yield of 17%. Cleavage of the methoxymethyl group of the Fmoc derivative 12 with catalytic amounts of p-toluenesulfonic acid in methanol afforded (+)-(2S,3S)-2-(2-morpholin-2-yl-2-phenylmethoxy)phenol 2. The synthetic utility as well as the configuration of compound 2 has been demonstrated by converting (S,S)-2-(2-morpholin-2-yl-2-phenylmethoxy)phenol 2 to (2S,3S)-2-[alpha-(2-ethoxyphenoxy)phenylmethyl]morpholine (1) and (2S,3S)-2-(2-methoxyphenoxy) benzyl)morpholine (16), two potential norepinephrine reuptake inhibitors under clinical evaluation.     

DOTA tris(phenylmethyl) ester: a new useful synthon for the synthesis of DOTA monoamides containing acid-labile bonds.

The synthesis of DOTA tris(phenylmethyl) ester 2, a new monoreactive derivative of DOTA, is described. This versatile synthon can be easily coupled to compounds bearing an amino group and then deprotected to DOTA monoamide under mild and neutral conditions by catalytic hydrogenolysis. Accordingly, compound 2 has been used in the synthesis of a DOTA monoamide gadolinium complex containing two palmitic esters, which is a component of mixed micelles as MRI contrast agents.     

Novel inhibitors of the hepatitis C virus NS3 proteinase

The hepatitis C virus proteinase inhibitor 4-methyl-1-(phenylmethyl)-2,6-pyridinedione 1 undergoes a novel autoxidation process, on silica gel, leading to the dimer 2 as the major product, a relatively more potent inhibitor of the enzyme.     

鸡屎藤挥发油化学成分的研究

利用气相色谱－质谱联用（ＧＣ／ＭＳ）技术对鸡屎藤挥发油化学成分进行分析研究,初步鉴定了３１种成分,它们占挥发油总量的７７．１６％,其中含量友上的有乙氧戊烷、乙酸异戊酯、苯甲醛、己酸乙酯、甲酸苯甲酯、乙酸苯甲酯、乙酸－２－苯乙酯、５,６,７,７ａ－四氢－４,４,７ａ－三甲基－２（４Ｈ）－苯并呋喃酮、十五碳酸乙酯、十六碳酸和癸酸异戊酯等１１种成分。     

Novel agents combining platelet activating factor (PAF) receptor antagonist with thromboxane synthase inhibitor (TxSI)

Compounds 1 or 2 which possess dual-acting PAF antagonist/TxSI in a previous paper were modified and evaluated for the dual-acting activity. It was found that several compounds were potent dual-acting PAF antagonist/TxSI in and ex vivo. 6-(2-Chlorophenyl)-3-[4-[(E/Z)-6-ethoxycarbonyl-1-(3-pyridyl)-1-hexenyl]phenylmethyl]-8,11-dimethyl-2,3,4,5-tetrahydro-8H-pyrido[4',3': 4,5]thieno[3,2-f]triazolo[4,3-a]diazepine (12) is excellent orally dual-acting PAF antagonist/TxSI.     

The absolute configuration of benproperinium dihydrogen phosphate, an antitussive drug

The (+)- and (-)-enantiomers of benproperinium dihydrogen phosphate, an antitussive drug, have been assigned the R- and S-configurations, respectively, by syntheses of both enantiomers using (S)-2-hydroxypropanoic acid (L-lactic acid) as chiral synthon. The key intermediate, (S)-1-methyl-2-[2-(phenylmethyl)phenoxy]ethyl p-toluenesulfonate, was subjected to an SN2-type reaction with piperidine furnishing (+)-(R)-benproperinium dihydrogen phosphate. (-)-(S)-Benproperinium dihydrogen phosphate was obtained by submitting the same tosylate to two consecutive SN2-type reactions with Br- and piperidine, respectively, acting as nucleophiles.     

Piperazinyl benzamidines: synthesis and affinity for the delta opioid receptor.

Piperazinyl benzamidines were prepared and found to bind to the rat delta (delta) opioid receptor. The most active compounds had a N,N-diethylcarboxamido group and a N-benzyl piperazine. The most potent among these was N,N-diethyl-4-[4-(phenylmethyl)-1-piperazinyl][2-(trifluoromethyl)phenyl]iminomethyl]benzamide (27) with a 1.22nM K(i) for the rat delta opioid receptor and ca. 1000 x selectivity relative to the mu opioid subtype.     

N-alkyl-4-[(8-azabicyclo[3.2.1]-oct-3-ylidene)phenylmethyl]benzamides, micro and delta opioid agonists: a micro address

The tertiary amide delta opioid agonist 2 is a potent antinociceptive agent. Compound 2 was metabolized in vitro and in vivo to secondary amide 3, a potent and selective micro opioid agonist. The SAR of a series of N-alkyl-4-[(8-azabicyclo[3.2.1]-oct-3-ylidene)phenylmethyl]benzamides was examined.     

Studies on the synthesis of the hypermodified base isolated from rat liver phenylalanine transfer ribonucleic acid

Oxidation of methyl (S,E)-4-[4,9-dihydro-4,6-dimethyl-9-oxo-1- (phenylmethyl)-1H-imidazo[1,2-alpha]purine-7-yl]-2-[(methoxycarbonyl) amino]-3-butenoate (3) with osmium tetroxide/N-methylmorpholine N-oxide provided a mixture of diastereomers 4 and 7. Hydrogenolysis of the major dihydroxy compound 4 over Pd-C gave beta-hydroxywybutine [[R-(R*,S*)]-1]. The minor isomer 7 was transformed into [S-(R*,R*)]-1 through the cyclic carbonate 8.     

Identification and quantitative determination of benproperine metabolites in human plasma and urine by liquid chromatography-tandem mass spectrometry

Two novel metabolites of benproperine (BPP), 1-[1-methyl-2-[2-(phenylmethyl)phenoxy]ethyl]-3-piperidinol (3-OH-BPP) and 1-[1-methyl-2-[2-(phenylmethyl)phenoxy]ethyl]-4-piperidinol (4-OH-BPP), were confirmed by comparison of retention times and mass spectra with those of synthetic standards using liquid chromatography-tandem mass spectrometry. Selective and sensitive procedures were developed for the simultaneous determination of BPP, 3-OH-BPP and 4-OH-BPP in human plasma and urine. The analytes were extracted from plasma sample and enzymatically hydrolyzed urine samples by liquid-liquid extraction, separated through a Diamonsil C(18) column (150 mm x 4.6 mm i.d.) and determined by tandem mass spectrometry with an electrospray ionization interface in selected reaction monitoring mode. Dextromethorphan was used as internal standard. The mobile phase consisted of acetonitrile-water-formic acid (34:66:1, v/v/v), and flow-rate was 0.5 ml min(-1). This method has a lower limit of quantification (LLOQ) of 60, 4.0 and 4.0 nmol l(-1)for BPP, 3-OH-BPP and 4-OH-BPP in plasma, 4.9, 4.7 and 2.4 nmol l(-1) in urine, respectively. The intra- and inter-run precision were measured to be below 9.2%, and the accuracy was within +/-4.3% for the analytes. The method was successfully used to determine BPP, 3-OH-BPP and 4-OH-BPP in plasma and urine for pharmacokinetic investigation. The results indicated residue of 3-OH-BPP in the body at least 192 h after an oral dose of BPP.     

Phosphate uptake in the yeast Candida tropicalis: purification of phosphate-binding protein and investigations about its role in phosphate uptake

The purification of a phosphate-binding protein (P_iBP₂) by immunoadsorption is described. The entire anti phosphate-binding protein 2 antibodies as well as the Fab fragments obtained from these antibodies inhibit P_i uptake by whole cells. The inhibition is a mixed type of inhibition (V _m and K _m are affected). These results should be regarded as a possible involvement of phosphate-binding protein 2 in P_i uptake. The binding of ¹²⁵I-labelled fragments prepared from anti phosphate-binding protein 2 antibodies to whole cells, to shocked cells and to protoplasts has been investigated. The results confirm the release of phosphate-binding protein by osmotic shock and during protoplast formation. From these findings, a cell-wall localisation, near the cell surface of the phosphate-binding protein should be proposed.Abbreviations P_i inorganic phosphate - P_iBP phosphate-binding protein - Tris Tris (hydroxymethyl)-aminoethane - MES (2(N-Morpholino) ethanesulfonic acid - BSA bovine serum albumin - EDTA ethylene diamine tetraacetic acid, disodium salt - PMSF phenylmethyl sulfonyl fluoride - SDS sodium dodecyl sulfate - Fab fragments, fragment antigen binding     

Histamine formed in stimulated human platelets is cytoplasmic

The localization of histamine formed by human platelets in response to agonists was evaluated. 87 +/- 5% of the histamine in a suspension of platelets exposed to phorbol-12-myristate-13-acetate (PMA) was associated with the platelet pellet. Incubation of saponin-permeabilized platelets with the intracellular histamine antagonist, N,N-diethyl-2-[4-(phenylmethyl)phenoxy]ethanamine.HCl (DPPE), released 75 +/- 3.9% of the histamine into the supernatant. Under conditions where 90% of platelet serotonin was secreted into the supernatant, the majority (80%) of platelet histamine remained associated with the pellet. The results suggest that histamine synthesized in response to agonists is largely cytoplasmic.     

Stimulation of in vivo tumor growth and phorbol ester-induced inflammation by N,N-diethyl-2-[4-(phenylmethyl)phenoxy] ethanamine HCl, a potent ligand for intracellular histamine receptors

We have implicated histamine as a mediator of proliferation through its binding to novel intracellular receptors (HIC), closely associated with antiestrogen binding sites (AEBS) in microsomes and nuclei. N,N-diethyl-2-[4-(phenylmethyl)phenoxy]ethanamine HCl (DPPE), is a potent ligand for AEBS/HIC. We now demonstrate that DPPE stimulates in vivo tumor growth (DMBA-induced mammary cancer in Sprague-Dawley rats and L5178Y leukemia in DBA/2 mice) and synergizes with phorbol-12-myristate-13-acetate (PMA) to induce inflammation and mitotic activity in mouse epidermis. Thus, ligands for intracellular histamine receptors may represent a new class of tumor promoting agents; this finding lends new credence to an important role for histamine in growth.     

Synthesis and comparative conformational energetics of D-phenylalanylsarcosine and its cyclic dehydration product, (R)-1-methyl-3-(phenylmethyl)-2,5-piperazinedione

Summary Synthetic protocols are presented both for D-PheSar and the corresponding cyclised diketopiperazine, prepared from N-t-butoxycarbonylprotected D-PheSar. Deprotection conditions could be manipulated to yield either D-Phenylalanylsarcosine or (R)-1-methyl-3-(phenylmethyl)-2,5-piperazinedione. Molecular modelling revealed several low energy conformers which contained a Z-peptide bond and which were readily amenable to cyclisation. Cyclisation was found by HPLC to be fastest in strongly acidic conditions.Abbreviation HBTU o-Benzotriazolyl-tetramethyluronium hexafluorophosphate     

On the appearance of Bacillus subtilis intracellular serine protease in the cell membrane and culture medium

While about 80% of the cell-bound intracellular serine protease of Bacillus subtilis A-50 have been recovered in the soluble fraction upon disruption of cells, the rest of the enzyme was found to be associated with the membrane fraction. Soluble cytoplasmic intracellular serine protease, as well as membrane-bound serine protease liberated by nonionic detergent treatment, have been isolated in a pure state and shown to be identical. The same protease might also be found extracellularly, due presumably to cell lysis or altered membrane permeability. Intracellular serine protease of Bacillus subtilis A-50 was clearly related to Bacillus subtilis serine proteases W1 and bacillopeptidase F described as extracellular enzymes.Abbreviations ISP intracellular serine protease - ISP-A-Bsu A-50 and ISP-B-Bsu A-50 molecular forms A and B of B. subtilis A-50 intracellular serine protease, respectively - SDS sodium dodecyl sulfate - PMSF phenylmethyl sulfonylfluoride - pNA p-nitroanilide - Buffer A 50 mM Tris-(hydroxymethyl)aminomethane-1 mM CaCl₂ adjusted to pH 8.5 with HCl     

Synthesis and biological activity of novel pyrimidinone containing thiazolidinedione derivatives

A series of pyrimidinone derivatives of thiazolidinediones were synthesized. Their biological activity were evaluated in insulin resistant, hyperglycemic and obese db/db mice. In vitro PPARgamma transactivation assay was performed in HEK 293T cells. PMT13 showed the best biological activity in this series. PMT13 (5-[4-[2-[2-ethyl-4-methyl-6-oxo-1,6-dihydro-1-pyrimidinyl]ethoxy]phenylmethyl]thiazolidine-2,4-dione) showed better plasma glucose, triglyceride and insulin-lowering activity in db/db mice than rosiglitazone and pioglitazone. PMT13 showed better PPARgamma transactivation than the standard compounds. Pharmacokinetic study in Wistar rats showed good systemic exposure of PMT13. Twenty-eight day oral toxicity study in Wistar rats did not show any treatment-related adverse effects.