Synthesis of 2'-aminomethyl derivatives of N-(2-(phosphonomethoxy)ethyl) nucleotide analogues as potential antiviral agents

A series of purine and pyrimidine N-(2-(phosphonomethoxy)ethyl) derivatives bearing aminomethyl, (dimethylamino)methyl, morpholinomethyl, and (trimethylammonio)methyl groups at the 2'-position were synthesized. The compounds were prepared by alkylation of the heterocyclic bases with appropriately substituted (aminoalkyl)oxiranes followed by condensation of the resulting intermediates with dialkyl ((p-tolylsulfonyl)oxy)methanephosphonate and subsequent treatment of the obtained diester with bromotrimethylsilane. 9-(3-Amino-2-(phosphonomethoxy)propyl)adenine (2a) proved active against varicella zoster virus (VZV), cytomegalovirus (CMV), and Moloney murine sarcoma virus (MSV) in the concentration range of 7-35 micrograms/mL. None of the other aminoalkyl derivatives demonstrated significant antiviral activity against herpes simplex virus type 1 and 2 (HSV-1 and HSV-2), VZV, (CMV), vaccinia virus (VV), MSV, and human immunodeficiency virus type 1 and 2 (HIV-1 and HIV-2).     

Novel (E)-5-(2-iodovinyl)-2'-deoxyuridine derivatives as potential cytostatic agents against herpes simplex virus thymidine kinase gene transfected tumors

(E)-5-(2-Iodovinyl)-2'-deoxyuridine (IVDU), its 2'-fluoro-substituted derivatives IVFRU (with fluorine in the ribo configuration), IVFAU (with fluorine in the ara configuration), and the corresponding 3'-chemical delivery system (CDS), or 3'-O-(1-methyl-1,4-dihydropyridyl-3-carbonyl)- substituted derivatives IVDU-CDS, IVFRU-CDS and IVFAU-CDS were evaluated for their cytostatic activity against wild-type (FM3A/O), thymidine kinase (TK)-deficient (FM3A/TK-), and herpes simplex virus type 1 (HSV-1) or HSV-2 thymidine kinase (tk) gene-transfected murine mammary carcinoma FM3A cells (FM3A TK-/HSV-1 TK+ and FM3A TK-/HSV-2 TK+). The test compounds proved highly inhibitory to the proliferation of HSVtk gene-transfected FM3A cells. Their cytostatic activity was within the 0.002 to 0.80 microM range, a compound concentration that is 1000- to 10,000-fold lower than that required to inhibit proliferation of wild-type FM3A/O cells. The target for the cytostatic activity of the test compounds is the cellular thymidylate synthase. In contrast to the parent IVDU compound, IVFRU and IVFAU and their CDS-substituted derivatives proved resistant to phosphorolytic cleavage by human and bacterial thymidine phosphorylase and should be considered as promising candidate compounds for further evaluation for combined gene/chemotherapy of HSVtk gene-transfected tumor cells in animal models.     

Heteroaromatic analogs of 1-[2-(diphenylmethoxy)ethyl]- and 1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazines (GBR 12935 and GBR 12909) as high-affinity dopamine reuptake inhibitors

A new series of heteroaromatic GBR 12935 [1-[2-(diphenylmethoxy)ethyl]-4-(3-phenylpropyl)-piperazine] (I) and GBR 12909 [1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine] (2) analogs was synthesized and evaluated as dopamine transporter (DAT) ligands. Analogs 5-16, in which the benzene ring in the phenylpropyl side chain of the GBR molecule had been replaced with a thiophene, furan, or pyridine ring, exhibited high affinity and selectivity for the DAT vs serotonin transporter (SERT) and stimulated locomotor activity in rats in a manner similar to the parent compound 2. In cocaine and food self-administration studies in rhesus monkeys, both thiophene-containing (6 and 8) and pyridine-containing (14 and 16) derivatives displayed potency comparable to 2 in decreasing the cocaine-maintained responding at the doses tested (0.8, 1.7, and 3 mg/kg). However, these compounds did not produce the degree of separation between food- and cocaine-maintained responding that was seen with 2. Among the bicyclic fused-ring congeners 17-38, the indole-containing analog of 2, 22, showed the greatest affinity for binding to the DAT, with IC50 = 0.7 nM, whereas the corresponding indole-containing derivative of 1, 21, displayed the highest selectivity (over 600-fold) at this site vs the SERT site.     

Synthesis and structure-activity relationships of 7-(2-aminoalkyl)morpholinoquinolones as anti-Helicobacter pylori agents

A series of the titled compounds was synthesized and tested for anti-Helicobacter pylori activities. We discovered Y-34867 having the most potent activity against Helicobacter pylori among the quinolones tested along with high photostability. Furthermore, Y-34867 showed an excellent therapeutic effect in the experimental Helicobacter pylori infected Mongolian gerbil model.     

Cationic phosphonolipids as nonviral gene transfer agents in the lungs of mice

With the aim of developing new gene transfer tools for treating CF with gene therapy, we have synthesized a novel family of molecules named cationic phosphonolipids. The most efficient among them were selected by in vitro screening to compare their activities in vivo in mouse lungs. We used a reporter gene whose activity was measured cytofluorimetrically (FACS-Gal assay) and by means of a chemiluminescence technique. These tests allowed us to identify the percentage of transfected cells and to quantify total beta-galactosidase in the lungs. This enabled us to identify two molecules, significantly efficient in comparison with DNA alone: GLB73 (p = 0.0015) and GLB253 (p = 0.007). Their use resulted in a time lag between transfection and maximum efficiency: maximum efficiency was observed 4 days after transfection with GLB73, whereas it was noticeable only on day 7 with GLB253. Moreover, from toxicity studies carried out in vivo, GLB73 seems to be nontoxic. In vivo results were correlated with in vitro results obtained with CF epithelial cell lines. Consequently, GLB73 is a potential candidate for phase I clinical trials in humans.     

Review of the biological response to a novel bone cement containing poly(ethyl methacrylate) and n-butyl methacrylate

This review describes work published independently elsewhere in which the biological reactions to poly(ethyl methacrylate) n-butyl methacrylate (PEMBMA) have been studied. This material has been compared throughout with conventional poly(methyl methacrylate) (PMMA). Butyl methacrylate monomer used in PEMBMA was slightly less toxic than methyl methacrylate monomer used in PMMA when injected intraperitoneally in mice. No differences in cardiorespiratory effects were found between n-butyl and methyl monomer infused intravenously into anaesthetized rabbits. The tissue reaction to the beaded polymers of poly(methyl methacrylate) and poly(ethyl methacrylate) implanted subcutaneously was identical. The surface appearance of the two materials differed significantly when viewed by scanning electron microscopy, showing a series of elevations resembling tightly packed spheres in the case of PMMA, but a smooth surface with only occasional smooth elevations in the case of PEMBMA. Intramuscular implantation showed more fibrous tissue and tissue damage in relation to PMMA cured in situ compared with PEMBMA and there was more bone necrosis and a thicker fibrous tissue layer adjacent to PMMA than PEMBMA when cured intraosseously.     

2,6-dialkylpiperazines. VIII (1)-N1-arylalkyl-N4-(2'-pyridyl)-2,6-dimethylpiperazines as adrenolytic and vasodilator agents

A series of cis and trans N1-arylalkyl-N4-(2'-pyridyl)-2'6-dimethylpiperazines were synthetized and tested as adrenolytic and vasodilator agents. The N1-substitution with the 3,4-dimethoxyphenethyl group seems the most promising with regard to pharmacological activity, which was found to reside mainly in the trans isomer (3-II b). The adrenolytic activity of (3-II b) is comparable with that of the related 2-methyl derivative (1-III), while it is higher than that of (IV) in which the piperazine nucleus is C-unsubstituted.     

2''-(Trimethylammonio)ethyl 4-(hexadecyloxy)-3(S)-methoxybutanephosphonate: a novel potent antineoplastic agent

The ability to successfully reuse OKT3, a mouse monoclonal antibody, is dependent upon the host's response to the antibody during and following the first treatment course. Antiidiotypic and/or antiisotypic antibodies may develop after exposure to OKT3. Antiidiotypic antibodies will bind OKT3, rendering it ineffective, while antiisotypic antibodies do not influence the efficacy of OKT3. A new membrane-based immunoassay, Transtat OKT3 (Sangstat Medical Corp, Menlo Park, CA) detects anti-OKT3 antibodies in less than 15 min. It allows simultaneous detection of antiidiotype and antiisotype antibodies. A total of 180 serum samples were initially analyzed by ELISA; results were negative, low-titer (1:100), or high-titer (> or = 1:1000). Retrospectively, these same samples were analyzed by Transtat for both anti-OKT3 (idiotype) and IgG2a (isotype). A total of 109 samples of 180 (60.6%) tested negative by ELISA and Transtat, while 71 (39.4%) tested positive. Of the negative samples by ELISA, 98 of 109 (89.9%) also tested anti-OKT3-negative by Transtat. Of the 109 specimens that were anti-OKT3 negative by Transtat, 98 (89.9%) tested negative by ELISA. There were 22 discrepant samples between the two methods; all were low-titer-positive (ELISA and Transtat). The 71 positive ELISA samples consisted of 53 low-titer (1:100) and 18 high-titer (> or = 1:1000), while the 71 anti-OKT3 positive Transtat samples consisted of 44 low-titer (1:10) and 27 high-titer (1:50). Sixty of 71 (84.5%) ELISA-positive samples were also positive by Transtat. Similarly, 60 of 71 (84.5%) Transtat-positive samples were also positive by ELISA. Of 71 patient samples positive for anti-OKT3 antibodies, 63 had an antiisotypic component present by Transtat. In conclusion, the Transtat OKT3 assay for measuring OKT3 and IgG2a antibodies offers a rapid and accurate assay for OKT3 monitoring.     

Synthesis and structure-activity relationships of 2-pyridones: II. 8-(Fluoro-substituted pyrrolidinyl)-2-pyridones as antibacterial agents

The 8-position side chain of 2-pyridones is believed to be involved in the binding with bacterial DNA gyrase to form the ternary complex, making them very important for the activity of 2-pyridones. A series of 2-pyridones having fluoro-substituted amines at the 8-position has been synthesized and their antibacterial activities and parmacokinetic properties are reported.     

2-Phenyl-4-(aminomethyl)imidazoles as potential antipsychotic agents. Synthesis and dopamine D2 receptor binding

A series of 2-phenyl-4-(aminomethyl)imidazoles were designed as conformationally restricted analogs of the dopamine D2 selective benzamide antipsychotics. The title compounds were synthesized and tested for blockade of [3H]YM-09151 binding in cloned African green monkey dopamine D2 receptor preparations. The binding affinity data thus obtained were compared against that of the benzamides and a previously described series of 2-phenyl-5-(aminomethyl)-pyrroles.     

Production of ethyl (R)-2-hydroxy-4-phenylbutanoate via reduction of ethyl 2-oxo-4-phenylbutanoate in an interface bioreactor

Ethyl (R)-2-hydroxy-4-phenylbutanoate [(R)-EHPB], a useful intermediate for the synthesis of various anti-hypertension drugs, was produced via microbial reduction of ethyl 2-oxo-4-phenylbutanoate [EOPB] in an interface bioreactor. Rhodotorula minuta IFO 0920 and Candida holmii KPY 12402 were selected as the best type culture and isolated yeasts, respectively. The highest enantiomeric excess of (R)-EHPB produced by R. minuta and C. holmii were 95 and 94%, respectively. C. holmii was used for the reduction of EOPB in a pad-packed interface bioreactor (inner volume, 3 liter). After incubation for 4 days, 4.4 g of (R)-EHPB was obtained via extraction with methanol followed by column chromatography. The overall yield, chemical purity, and enantiomeric excess of (R)-EHPB were 58%, 99.1%, and 90%, respectively.     

Synthesis and properties of 2-S-(N,N-dialkylamino)ethyl)thio-1,3,2-dioxaphosphorinane 2-oxide and of the corresponding quaternary derivatives as potential nontoxic antiglaucoma agents

A new series of cyclic organophosphorus esters, 2-S-[2'-N,N-dialkylamino)ethyl]thio-1,3,2-dioxaphosphorinane 2-oxide and their quaternary derivatives, was synthesized and studied as potential antiglaucoma agents. Thes compounds inhibit acetylcholinesterase (E.C.3.1.1.7)at a bimoecular rate constant (ki) in the range of 10(3)-10(4) M-1 min-1. Values of the affinity (K) and phosphorylation (k') rate constants for this enzyme indicate that k' is responsible for the relatively low values of ki as compared with similar data for the open-chain analogues, O,O-diethyl phosphorothiolates (10(6) M-1 min-1). The mammalian toxicity of the new compounds in terms of acute LD50 values in mice is 1-3 x 10(3) less than that of phospholine, an open-chain analogue. In an initial clinical trial, one member of the new series (alkyl = C2H5) caused a significant decrease of intraocular pressure in aphakic glaucoma, while phospholine proved to be ineffective.     

Use of 2-isocyanatoethyl methacrylate and iron (II) perchlorate for bonding tri-n-butylborane-initiated luting agents to dentin

The present study investigated the effect of 2-isocyanatoethyl methacrylate (IEM) and iron (II) perchlorate on dentin adhesion. Four primers were evaluated, consisting of aqueous 2-hydroxyethyl methacrylate (HEMA) solutions containing 5, 10, 20 or 50 micromol/g iron (II) perchlorate. Five luting agents were prepared with methyl methacrylate (MMA), poly(methyl methacrylate) (PMMA), tri-n-butylborane (TBB) initiator and IEM. The concentrations of IEM in the luting agents were 0.2, 0.4, 0.8, 2.0 and 4.0 wt%. Extracted bovine teeth were ground to expose the dentin, etched with an aqueous solution of 10 wt% phosphoric acid, primed, and then bonded with stainless-steel rods; tensile bond strengths were determined after 1 d immersion in water. The highest bond strength (20.7 MPa) was recorded for the group using 10 micromol/g iron (II) perchlorate and 2.0 wt% IEM. The use of IEM was effective in decreasing the optimal concentration of iron (II) perchlorate, and this may contribute to the color stability of iron-containing pretreatment agents.     

Retrovirus-mediated gene transfer of the multidrug resistance-associated protein (MRP) cDNA protects cells from chemotherapeutic agents

Transduction of hematopoietic progenitors with a multidrug resistance gene like mdr-1 or mrp aims to protect bone marrow from toxicity of chemotherapeutic agents. The interest in the use of mrp as an alternative to mdr-1 gene transfer for bone marrow protection lies in its different modulation. Indeed, classical P-gp reversal agents, tested in the clinic to decrease mdr-1 tumor resistance, have little or no effect on MRP function. This would allow, in the same patient, the use of reversal agents to decrease P-gp tumor resistance without reversing bone marrow protection of the transduced hematopoietic cells provided by multidrug resistance-associated protein (MRP). As a first step, we have constructed and tested two different mrp-containing vectors with either the Harvey retroviral long terminal repeat (LTR) or PGK as promoters and generated ecotropic producer cells. We have shown by Southern blot analysis that retroviral supernatant from these producer cells can efficiently transmit the mrp gene to target cells. Mrp expression could be detected by fluorescence-activated cell sorting (FACS) analysis in the producer cells. The transduced cells have increased resistance to doxorubicin, vincristine, and etoposide. Furthermore, chemoprotection of the transduced cells was increased after selection with chemotherapeutic agents in the presence of glutathione, a co-factor for MRP function. These data indicate that mrp retroviral vectors may be useful for chemoprotection and selection.     

Development of novel, potent, and selective dopamine reuptake inhibitors through alteration of the piperazine ring of 1-[2-(diphenylmethoxy)ethyl]-and 1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazines (GBR 12935 and GBR 12909)

The design, synthesis, and biological evaluation of compounds related to the dopamine (DA) uptake inhibitors: 1-[2-(diphenylmethoxy)ethyl]-4-(3-phenylpropyl)piperazine (1) and 1-[2-[bis-(4-fluorophenyl)methoxy]ethyl]-4-(3-phenylpropyl)piperazine (2) (GBR 12395 and GBR 12909, respectively), directed toward the development and identification of new ligands interacting with high potency and selectivity at the dopamine transporter (DAT) is reported. The substitution of the piperazine ring in the GBR structure with other diamine moieties resulted in the retention of the high affinity of new ligands for the DAT. Some of the modified GBR analogs (e.g. 8, 10, (-)-49, or (-)-50) displayed substantially higher selectivity (4736- to 693-fold) for the dopamine (DA) versus the serotonin (5HT) reuptake site than the parent compounds. The bis(p-fluoro) substitution in the (diphenylmethoxy)ethyl fragment slightly increased the affinity of the ligands at the DA reuptake site but reduced their selectivity at this site (e.g. 9 and 8, 11 and 10, or 17 and 16, respectively). Congeners, such as the series of monosubstituted and symmetrically disubstituted piperazines and trans-2,5-dimethylpiperazines, which lack the (diphenylmethoxy)ethyl substituent lost the affinity for the DAT yet exhibited very high potency for binding to the sigma receptors (e.g.28). The chiral pyrrolidine derivatives of 1, (-)-49, and (+)-49, exhibited an enantioselectivity ratio of 181 and 146 for the inhibition of DA reuptake and binding to the DAT, respectively.     

N-(2-(4-hydroxyphenyl)ethyl)-4-chlorocinnamide: a novel antagonist at the 1A/2B NMDA receptor subtype

A series of N-(2-phenethyl)cinnamides was synthesized and assayed for antagonism at three N-methyl-D-asparate (NMDA) receptor subtypes (NR1A/2A-C). N-(2-(4-hydroxyphenyl)ethyl)-4-chlorocinnamide (6) was identified as a highly potent and selective antagonist of the NR1A/2B subtype.