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At least 19 recordsLinked to original sources

PubMed1978

[Chemical and pharmaceutical research on pyran derivatives. X. Synthesis of 1-oxo-2-alkyl-3-dialkylamino-1H-naphtho[2,1b]pyrans].

When reaction of N,N-dialkyl-alpha-ethoxycarbonyl-alpha-alkylacetamides with beta-naphthol in the presence of phosphorus oxychloride was carried out in chlorobenzene at reflux, formation of 1-oxo-2-alkyl-3-dialkyl-amino-1H-naphtho[2,1-b]pyrans was achieved together with some other products whose structure was defined. Moreover, substitution of the 2 position of 1-oxo-3-dialkylamino-1H"naphtho[2,1-b]pyrans with chlorine or cyano group as well as the preparation of 1-thio-3-dialkylamino-1H-naphtho[2,1-b]pyrans was obtained by suitable chemical methods. Pharmacological screening of these compounds showed the lack of psychotropic activity of the corresponding 1-oxo-3-dialkylamino-1H-naphtho[2,1-b]pyrans.

Animals↗

PubMed1978

[Chemical and pharmaceutical research on pyran derivatives. XI. Synthesis of 2-dialkylamino-4-oxo-10-methyl-4H-naphtho[2,3b]pyrans].

Reaction of N,N-dialkylethoxycarbonylacetamides with 1-methyl-2-naphthol, in the presence of phosphorus oxychloride, gave rise to the formation of 2-dialkylamino-4-oxo-10-methyl-4H-naphtho[2,3-b] pyrans through the preliminary attack of the amide-phosphorus oxychloride reactant at the phenolic hydroxyl and cyclization at position 3 of the naphthalene moiety. However when (N-alkyl,N-phenyl)ethoxycarbonylacetamides were used in the reaction an ortho position of the N-phenyl group was involved in the cyclization and 1-alkyl-2(1'-methyl-2'-naphthoxy)-4-quinolones were achieved. Pharmacological investigation showed that some naphtho[2,3-b]pyran derivatives have neurotropic activity of the sedative, anticonvulsant and antidepressant type very similar to that shown by previously studied 1-oxo-3-dialkylamino-1H-naphtho[2,1-b]pyrans (5).

Amphetamine↗

PubMed1978

Cell and tissue distribution of 14C-labeled pyran copolymer.

The tissue distribution of pyran (maleic anhydride-divinyl ether) copolymer was studied after a single ip injection of 14C-labeled pyran (25 mg/kg) to mice. The pyran showed a reticuloendothelial distribution with the liver and spleen containing the highest concentrations which persisted for at least 21 days after drug treatment. Blood levels of 14C-pyran reached a peak 2 hours after injection and were cleared within 6 hours. Attempts to measure uptake of 14C-pyran by peritoneal macrophages were unsuccessful due to an inability to recover macrophages between 3 and 24 hours after ip pyran administration. Since activated macrophages appear to be the primary mechanism by which pyran enhances host resistance to microbial infection and neoplasia, the uptake of 14C-pyran by isolated peritoneal macrophages in vitro was studied. Purified macrophages showed a gradually increasing uptake of 14C-pyran, and a large amount of cell-associated radioactivity was bound to trichloroacetic acid-precipitable material. Several polyanions, including unlabeled pyran, dextran sulfate, and poly(I)-poly(C), competed for acid-precipitable receptor molecules. The superior antitumor effects of pyran as compared to other polyanions may result from the continuous presence of the synthetic polymer in the host. Possible mechanisms of immunopotentiation by pyran are discussed.

Animals↗

PubMed1979

Activation of mouse macrophages by pyran copolymer and role in augmentation of natural killer activity.

Inoculation of mice with pyran copolymer resulted in activation of natural killer (NK) cells as well as macrophages. Conditions optimal for the boosting of NK activity seemed to differ from those optimal for macrophage activation as assessed by cytostasis of tumor target cells. Peak levels of macrophage cytostatic reactivity were found at about 7 days after drug injection and were only achieved by the highest doses of pyran tested. Macrophage activation was consistently higher in the peritoneal cavity than in the spleen, regardless of route of administration, in contrast to the failure of i.v. pyran to induce high NK reactivity in peritoneal exudate cells. At 2-3 days after pyran treatment of older mice, NK augmentation reached peak levels, but only minimal macrophage activation was found. Despite these differences, macrophages played a role in regulating NK activity in pyran-treated mice. Functional macrophages appeared to be required for augmentation of NK activity by pyran, since boosting was impaired by prior in vivo inoculation of silica. Macrophages also appeared able to inhibit NK activity. In younger mice that exhibited high spontaneous levels of NK activity, pyran treatment produced a substantial reduction in NK activity to levels below those of untreated mice. This depression coincided with the time of peak levels of macrophage cytostasis. Furthermore, removal of adherent cells from the spleen cells of these pyran-treated mice resulted in levels of NK activity almost as high as those of untreated mice. The possibility that the depression of NK activity in young mice by pyran copolymer is due to suppressor cells is discussed.

Animals↗

PubMed1978

Inhibition of deoxyribonucleic acid polymerases from human cells and from simian sarcoma virus by pyran.

Pyrans are co-polymers of divinyl ether and maleic anhydride. Four pyrans of various molecular weights more potently inhibited terminal deoxyribonucleotidyltransferase (EC 2.7.7.31) from a human cell line of acute lymphoblastic leukemia origin (Molt-4) than they did DNA polymerases alpha, beta and gamma from these cells and DNA polymerase from simian sarcoma virus. For example, the concentrations of one pyran required for 50% inhibition of terminal deoxynucleotidyltransferase, DNA polymerases alpha, beta and gamma and viral DNA polymerase were 0.9, 110, 125, 35 and 47 microgram/ml respectively. Quantitatively similar results were obtained with the other pyrans. Inhibition of these enzymes by pyran was dependent on the concentrations of both the bivalent cation and template/primer or initiator in assay mixtures, but not on the concentrations of the substrate (deoxyribonucleoside 5'-triphosphate), enzyme, or bovine serum albumin. These results suggested that pyran inhibited these enzymes by complexing bivalent cations, which caused a decreased affinity of template/primer or initiator for each enzyme and a decrease in enzyme activity.

Cell Line↗

PubMed1978

Effects of combined radiotherapy and immunotherapy with the use of pyran copolymer on murine fibrosarcoma.

A weakly immunogenic, 3-methylcholanthrene-induced, subcutaneous fibrosarcoma syngeneic to inbred C3H/HeJ mice was used. Pyran copolymer was injected either directly into the tumor, ip, or iv as soon as tumors appeared or when tumors were 8 mm in diameter. One, three, or five doses of pyran copolymer at 10 or 20 mg/kg/dose were injected, with multiple doses being given every other day. Pyran copolymer injected intratumorally once, three times, or five times significantly retarded tumor growth and prolonged the survival times of the hosts. Of the other routes and doses, only pyran copolymer given three times iv significantly retarded tumor growth, but none of these significantly prolonged the survival times of the hosts. Pyran copolymer alone did not induce any complete regression of tumor. Local tumor irradiation with a single exposure to 2,000 rads of X-ray induced complete regressions in some mice, but a higher percentage of tumor cure was observed when tumor irradiation was followed by pyran copolymer treatment.

Animals↗

PubMed1976

Antiviral effect of pyran against systemic infection of mice with herpes simplex virus type 2.

The immunomodulator pyran markedly protected 5-week-old mice from lethal intravenous infection with herpes simplex virus type 2. The 50% lethal dose was increased almost 100-fold in pyran-treated mice as compared with controls. Although the protection was not as marked in older mice (10 and 16 weeks old), there was a significant increase in mean survival time. When the pathogenesis of herpesvirus disease was monitored in control and drug-treated mice, the effect of pyran was most evident in the spinal cord, where virus was recovered from 20 of 25 control mice and from only 6 of 25 pyran-treated mice. There was also a significant reduction in the titer of virus present, and virus appeared later in the spinal cord of pyran-treated mice than in control mice. The protective effect of pyran was observed only when the drug was administered 24 h before viral challenge, was seen after both intraperitoneal and intravenous injection, and was not due to direct inactivation of the virus.

Age Factors↗

PubMed1977

Macrophage involvement in the protective effect of pyran copolymer against the Madison lung carcinoma (M109).

Pyran copolymer (NSC 46015) therapy markedly enhanced host resistance to a murine lung carcinoma (M109) implanted s.c. Multiple dose schedules were not significantly better than single doses at increasing lifespan. Although tumor necrosis was much more extensive in the lesions of pyran-treated mice, pyran copolymer was not directly toxic to M109 cells in vitro. A comparative histopathological study revealed an intense histiocytic reaction in the connective tissue surrounding the primary tumor in mice receiving pyran as compared to 0.9% NaCl solution-treated controls. Macrophages were often associated with necrobiotic tumor cells. Morphologically activated macrophages were recovered from pyran-treated animals which potently inhibited DNA synthesis of M109 tumor cells in vitro. This response peaked 6 days after drug treatment and was to a large extent specific for neoplastic cells. Our results from both in vivo and in vitro studies support the concept that pyran enhances host resistance to neoplasia by mobilization and activation of the reticuloendothelial elements of the host's defense.

Animals↗

PubMed1976

Products from furans. 1. Sunthesis and anticoccidial and antimicrobial activity of 5-amino-5,6-dihydro-6-methoxy-2-methyl-2-(4'-biphenylyl)-2H-pyran-3(4H)-ones and related compounds.

A Michael type addition of an amine to 6-methoxy-2-methyl-2-(4'-biphenylyl)-2H-pyran-3(6H)-one (1) dissolved in ether, benzene, or THF gave 5-amino derivatives of 5,6-dihydro-6-methoxy-2-methyl-2-(4'-biphenylyl)-2H-pyran-3(4H)-one (2). These by subsequent reduction with LiAlH4 were converted to 5-amino derivatives of 6-methoxy-2-methyl-2-(4'-biphenylyl)tetrahydro-2H-pyran-3-ol (3). Both isomers A and B of 1 (in regard to the methoxy group at C6) were used for the synthesis of 2 and 3. The in vitro antimicrobial activity of the amine adducts 2 was of the same order of magnitude as the starting material. Amine adducts in general, however, were by far more active as coccidiostats than the starting material and retained their activities when they were reduced. 5,6-Dihydro-6-methoxy-2-methyl-2-(4'-biphenylyl)-5-(dimethylamino)-2H-pyran-3(4H)-one hydrochloride (A) and 5,6-dihydro-6-methoxy-2-methyl-2-(4'-biphenylyl)-5-(dimethylamino)-2H-pyran-3(4H)-one hydrochloride (B), prepared from isomer A and B of 1, respectively, were the most active as coccidiostats. These compounds when administered orally to chickens 1 day prior to infection at a concentration 0.05% in their diet gave them total protection against Eimeria tenella.

Anti-Bacterial Agents↗

PubMed1979

Effect of pyran on latency after herpes simplex virus infections.

The immunomodulator pyran protected mice against both herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections. In infections of the lip with HSV-1, prophylactic administration of pyran reduced the severity of the herpetic lesions and enhanced their resolution, but did not decrease the high incidence of development of latent HSV-1 infection of the trigeminal ganglia. In vaginal infections with HSV-2, prophylactic administration of pyran either systemically or locally reduced mortality, reduced the incidence of mice with vaginal HSV-2 infection, and did not alter the low incidence of latent infection of the spinal dorsal root ganglia. Pyran treatment before systemic herpetic infection after intravenous inoculation of HSV-2 also reduced mortality and virus replication, as evidenced by a decreased antibody response in the survivors, and it either reduced latent infection in the spinal dorsal root ganglia or did not predispose mice to latent infection. Treatment with the immunomodulator appeared to inhibit or reduce HSV infection early in viral pathogenesis in all three model systems, producing protection from clinical disease and resulting in less virus to induce a systemic antibody response, with either a reduction in latent virus infection or no enhancement of development of latency. In all of the HSV models, the development of latent herpetic infection was closely correlated with sufficient virus replication early in the infection to induce a systemic neutralizing-antibody response.

Animals↗

PubMed1979

Mobilization of murine hemopoietic stem cells (HSC) by Pyran Copolymer.

Pyran Copolymer, divinyl-ether maleic anhydride increases the concentration of circulating pluripotential stem cells in mice by a factor of 15 to 30. Maximal mobilization occurs five days after Pyran Copolymer injection with synchronous peaks of CFU-S and CFU-C. When Pyran fractions of defined molecular weight from 12,000 to 52,000 are injected into mice, mobilization of CFU-S and CFU-C parallels molecular weight. Hemopoietic stem cells are mobilized from bone marrow into peripheral blood and subsequently trapped in the spleen.

Animals↗

PubMed1979

Enhancement of erythroid target cells for Friend murine leukemia virus by intravenous pyran treatment.

Male BALB/c mice that received prophylactic iv treatment with pyran had significantly enhanced splenomegaly, an increased number of splenic foci induced by the spleen focus forming virus (SFFV) in the Friend murine leukemia virus (F-MuLV) complex, and a slightly decreased mean survival time as compared with untreated controls infected with F-MuLV. A corresponding increase in the lymphatic leukemia virus component of the F-MuLV complex was not observed, which suggests that the enhancement of the disease was due primarily to a selective increase in the SFFV component of the F-MuLV complex. That the enhancement was related to an increased number of target cells for SFFV was substantiated by data concerning erythropoiesis in iv pyran-treated animals. Increases in splenic hematocrits and in uptake of 59Fe in the spleens of animals treated iv with pyran provided quantitative evidence for the histologic finding of increased erythroid precursors in the spleens.

Animals↗

PubMed1979

[Chemical and pharmacological research on pyran derivatives. XIV. 3-alkylaminoaphtho/2,1-b/pyran-1-ones and derivatives].

3-Alkyl(phenyl)aminoaphtho[2,1-b]pyran-1-ones (III) were prepared from N-alkyl or N-phenylethoxycarbonylacetamides and 2-naphthol in the presence of phosphorus oxychloride, in order to evaluate their pharmacological activity on the CNS in comparison with previously described 3-dialkylaminoaphtho[2,1-b]pyran-1-ones. Compounds (III) gave 2-morpholinomethyl derivatives as well as N-acetyl and N-ethtoxycarbonyl derivatives. The reaction of (III) in which R = alkyl and N,N-dimethylformamide-POCl3 afforded 2-formyl derivatives and in some cases also 8-alkyl-9,10-bisdimethylaminoaphtho[1',2':5,6]pyrano[2,3-b]pyrrol-11(8H)-ones; when R = phenyl, only naphtho[1',2':5,6]pyrano[2,3-b]quinolin-14-one was obtained from the same reaction. Pharmacological evaluation showed that compounds (III) had a weak CNS depressant activity. Some of them also exhibited antagonist effect on reserpine-induced blepharospasm and hypothermia and on metrazole-induced seizures in the mouse. Within the limits of these activities a special behavior was found for the compound 3-ethylaminoaphtho[2,1-b]pyran-1-one [(III b) - K 12479].

Amphetamines↗

PubMed1977

[Chemical and pharmacological research on pyran derivatives. VII. Derivatives of naphto/1',2':5,6/pyran/2,3-c/pyrazole and of 12H-naphto/1',2':5,6/pyran/2,3-d/pyrimidine].

Reaction of substituted 1-oxo-3-dialkylamino-1H-naphtho[2,1-b]pyrans with N,N-dimethylformamide in the presence of phosphorus oxychloride afforded the corresponding substituted 1-oxo-2-formyl-3-dialkyl-amino-1H-naphtho[2,1-b]pyrans. Condensation of substituted 1-oxo-2-formyl-3-dimethylamino-1H-naphtho[2,1-b]pyrans with hydrazine or monosubstituted hydrazines led to the formation of 11-oxo-8H,11H-naphtho[1',2':5,6]pyrano[2,3-c]pyrazole derivatives through the intermediate hydrazones and subsequent cyclization. Similarly, condensation with acetamidine or guanidine gave rise to the formation of 12-oxo-12H-naphtho[1',2':5,6]pyrano[2,3-d]pyrimidine derivatives. Some of these compounds were tested for their pharmacological properties, but no noteworthy activity was observed.

Animals↗

PubMed1977

Reaction of dichloroketene and sulfene with N,N-disubstituted 6-aminomethylene-5,6,8,9-tetrahydro-7H-benzocyclohepten-7-ones. Synthesis of 5H-benzo(5,6)cyclohepta(2,1-b)pyran and 5H-benzo(5,6)cyclohepta(1,2-e)-1,2-oxathiin derivatives.

The 1,4-cycloaddition of dichloroketene to N,N-disubstituted 6-aminomethylene-5,6,8,9-tetrahydro-7H-benzocyclohepten-7-ones afforded N,N-disubstituted 4-amino-3,3-dichloro-3,4,10,11-tetrahydro-5H-benzo[5,6]cyclohepta[2,1-b]pyran-2-ones only in the case of full or partial aromatic N-substitution. The relative adducts gave N,N-disubstituted 4-amino-3-chloro-10,11-dihydro-5H-benzo[5,6]cyclohepta[2,1-b]pyran-2-ones by dehydrochlorination. The 1,4-cycloaddition with sulfene occurred readily in the case of both aliphatic and aromatic N-substitution to give N,N-disubstituted 4-amino-3,4,10,11-tetrahydro-5H-benzo[5,6]cyclohepta[1,2-e]-1,2-oxathiin-2,2-dioxides. These compounds, as well as the pyran derivatives, can be considered as linear heterocyclic analogues of the Amitriptyline ring system.

Cycloheptanes↗

PubMed1975

Affinity chromatography of viral DNA polymerases on pyran-sepharose.

Pyran covalently linked to cyanogen bromide-activated Sepharose has been shown to be an effective affinity matrix for several viral DNA polymerases. Differential salt elution of viral compared with cellular polymerases, as well as substrate elution, suggests the affinity nature for the matrix. Unlike some other affinity systems described, pyran-Sepharose is totally resistant to nuclease digestion and is stable at 4 degrees for several months. DNA polymerases isolated from several viruses by detergent treatment were recovered in good yield. Analysis of iodinated proteins by sodium dodecyl sulfate-gel electrophoresis revealed that the DNA polymerase of avian myeloblastosis virus found in crude preparations of the virus could be purified nearly to homogeneity by a single passage through the column. These results suggest that pyran-Sepharose is an effective affinity column that is potentially adaptable as part of a general purification procedure for viral DNA polymerases.

Animals↗

PubMed1979

Augmentation of natural killer activity by pyran copolymer in mice.

Treatment of older mice with pyran copolymer, a known interferon-inducer, was found to result in a rapid boosting of cell-mediated cytolytic activity against YAC-1 tumor target cells. The effector cells were characterized as being non-adherent and were presumed to be natural killer (NK) cells. Augmentation occurred in various lymphoid organs and was detectable 2-3 days after drug treatment. Differences in the levels of boosted activity among the lymphoid organs resulted when the route of administration was varied. The degree of augmentation was largely independent of the dose of pyran, but did vary among different strains of mice. Augmentation, moreover, was followed by a rapid decline by 5-7 days.

Adjuvants, Immunologic↗

PubMed1976

Role of divalent ion complex formation in pyran--inhibition of nucleic acid biosynthesis.

The degree of inhibition of mammalian DNA-dependent RNA polymerases I and II and Moloney leukemia virus RNA-dependent DNA polymerase by pyran copolymer was dependent on the concentration of the divalent cation cofactor in the reaction mixture. Inhibition was completely blocked by an excess of divalent cations. It was concluded that pyran inhibited these enzymes by complexing with the essential divalent cation cofactor.

Animals↗