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According to their chemical structure, asymmetric triazine derivatives have an activator or scavenger action in a superoxide radical generating system. Complexation with Cu2+ of one of the derivatives enhanced its scavenger activity.
The synthesis of derivatives of 5H-1,3,4-thiadiazolo[3,2-a]-s-triazine-5,7-dione substituted in position 2 and 6 is described. The compounds were subjected to pharmacological screening, and some were found to possess antiinflammatory and antipyretic properties.
The syntheses of some acetamides (II) and phenylureas (III) derived from 2-amino-5-alkoxyphenyl-1,3,4-oxa(thia)diazoles (I) and some 2-alkoxyphenyl-6-phenyl-1,3,4-oxa(thia)diazole-[3,2-a]-s- triazin-5,7-diones (IV) are described. Pharmacological tests showed antiinflammatory and analgesic activities of bicyclic derivatives. A probable influence of alkoxyphenyl substituents, present in three kinds of structures, was observed.
Glucose-6-phosphate dehydrogenase (EC 1.1.1.49) prepared from baker's yeast binds to immobilized Cibacron Blue F3G-A and Procion Red HE-3B. In this paper the two dyes are compared with respect to their use in the purification of this enzyme. Cibacron Blue chromatography was found useful at an early stage of purification for the removal of contaminating hexokinase, phosphoglucose isomerase and phosphoglucomutase. With Procion Red HE-3B Sepharose the NADP dependent enzymes phosphogluconate dehydrogenase and glutathione reductase are separable from glucose-6-phosphate dehydrogenase. Unlike Cibacron Blue gel chromatography, the enzyme can be specifically eluted from Procion Red HE-3B Sepharose by a NADP gradient. Other monochlorotriazine dyes like Xirone Brillant Red BHD, 4BHD, 6BHD and GHD and the dichlorotriazine dye Procion Brown MX-5BR immobilized to Sepharose have only little binding affinity to glucose-6-phosphate dehydrogenase. The binding behaviour of different immobilized triazine dyes for pre-purified and purified glucose-6-phosphate dehydrogenase is compared. In addition, the influence of the free dyes on the activity of glucose-6-phosphate dehydrogenase is studied. It is demonstrated that the results of kinetic and binding studies with the purified enzyme are not uncritically applicable for the selection of a dye as ligand for affinity chromatography during enzyme preparation.
The structures of xanthothricin (I) and fervenulin (II), pyrimido-[5,4-e]-1,2,4-triazine antibiotics were determined by x-ray analysis. The crystals of I and II are monoclinic: a 9.667(6), 18.270(7), b 14.029(9), 5.723(2), c 6.914(3), 18.058(7) A, beta 116.47(3), 118.90(2) degrees, Z 4,8; space group P21/c. Analysis of bond length distribution in I and II was indicative of significant alternation of the double and ordinary bonds.
Absorption, distribution and excretion of 2,4-diamino-6-(2,5-dichlorophenyl)-s-triazine maleate (MN-1695) were studied in rats, dogs and monkeys after administration of [14C]-MN-1695. MN-1695 was found to be well absorbed from the small intestine after oral administration in all species examined. Plasma level of unchanged MN-1695 reached a maximum at 1 to 4 h after oral administration of [14C]-MN-1695 in rats, dogs and monkeys. The mean elimination half-life of unchanged MN-1695 from plasma was about 3, 4 and 50 h in rats, dogs and monkeys, respectively. Tissue levels of radioactivity after oral administration of [14C]-MN-1695 in rats indicated that [14C]-MN-1695 was distributed throughout the body and the radioactivity in tissues disappeared with a rate similar to that in plasma. A stomach autoradiogram after intravenous administration of [14C]-MN-1695 in the rat revealed the radioactivity localized in the gastric mucosa where MN-1695 was assumed to exert its pharmacological activity. In pregnant rats, [14C]-MN-1695 was distributed to the fetus with levels similar to maternal blood levels. After oral administration of [14C]-MN-1695 in rats, 39 to 46% of the dose was excreted into the urine and 50 to 63% of the dose into the feces, within 96 h. In dogs, about 40% of the dose was excreted into the urine and about 50% of the dose into the feces, within 6 days after oral administration. In monkeys, within 14 days after oral administration, about 60 and 30% of the dose were excreted into the urine and feces, respectively, and the main excretion route was the urine.(ABSTRACT TRUNCATED AT 250 WORDS)
The interaction of yeast glucose 6-phosphate dehydrogenase with 31 triazine dye-stuffs was studied by means of affinity partitioning in an aqueous two-phase system using dye-liganded polyethyleneglycol and dextran as polymers. From the partition coefficients, K, of the enzyme in the presence and absence of the dye-polymer the term delta log K was calculated which corresponds to the actual interaction of the enzyme with the dye molecule. Quantitative data concerning the maximum extraction power delta logmax as well as the affinity of the dyes to the enzyme (expressed as percentage of dye-liganded polymer in the system at 0.5 X delta log Kmax) were derived. The influence of several effectors of the enzyme on the partition revealed that NADP+ and NADPH act competitively for a large number of dyes investigated.
Antifungal activity of compound I-476 (1,2-dihydro-3-methylpyrido[3,2-e]as-triazine dihydrochloride) was evaluated in vitro and in vivo. Minimal concentration inhibiting the growth of pathogenetic and saprophytic fungi in vitro ranged from 3.1 to 25 micrograms/ml. The in vivo experiments were performed in a model of experimental candidiasis in Balb/c mice. Antifungal activity of I-476 was measured by the survival time of the animals and the number of living Candida albicans cells in the kidney and spleen of the animals infected and then treated with the compound in question. A single intraperitoneal dose of I-476 markedly prolonged the survival time of mice with experimental candidiasis. The compound administered for 5 subsequent days, diminished the number of Candida albicans cells in the kidney and spleen or caused their complete elimination from these organs.
It has been found that the condensation of esters of 3H-2-imino-7-methyl-4-oxopyrido[3,2-e]-1,3-thiazine-5- and -6-carboxylic acids (I, II) with formaldehyde and primary amines affords the corresponding derivatives of a new heterocyclic system pyrido[3,2-e]-1,3-thiazino [3,2-a]-s-triazine (IX-XXIV).
A comparative study of the NMR 1H and 13C spectra of reumycin, fervenulin and xanthothricin in aqueous acid-base media showed that at pH or pD ranging from 8.0 to 1.0 the antibiotics were chemically stable. By the ratio of the 1H and 13C chemical shifts of reumycin at pH 4.0-10.0 the pKa values of this antibiotic were determined: 6.7 in aqueous (D2O) solution and 8.76 in dimethylsulfoxide media. Alkalization of the solutions of reumycin (pH 12.0), fervenulin (pH 9.0) and xanthothricin (pH 8.0) resulted in irreversible chemical transformation of the antibiotics. The analysis of the chemical shifts in the PMR spectra of the transformation products revealed transformation of the uracil ring in reumycin and uracil and triazine rings in fervenulin and xanthothricin. Alkalization of the xanthothricin solutions resulted also in demethylation with formation of reumycin.
Three treatments with 2,4 dioxo hexahydro triazine (DHT) significantly reduced the concentration of potato virus X (PVX) in systemically infected tobacco plants. In hypersensitive plants DHT caused a reduction in the number of local lesions produced by PVX. In systemic and hypersensitive hosts, treatment with DHT resulted in a more or less marked reduction in the concentration of, and in the number of local lesions caused by, potato virus Y (PVY), potato virus A (PVA), tobacco mosaic virus (TMV), and cucumber mosaic virus (CMV). Three days after treatment with DHT the incorporation of 32P into TMV RNA was significantly reduced, while that into host RNA was less affected.
Carboxypeptidase G1 (CPDG1), an enzyme that degrades folates but not the nonclassical folate antagonists triazinate (TZT, Baker's antifol) and 2,4-diamino-5-(3',4'-dichlorophenyl)-6-methylpyrimidine (DDMP), enhanced the antineoplastic activity of these antifolates. In 6-day cell culture experiments with Walker 256 carcinosarcoma, CPDG1 at levels up to 0.54 unit/ml showed very little inhibitory effect on growth. In the presence of 10(-7) M DDMP, the grown of Walker 256 cells was similar to that of controls, but in combination with CPDG1 (0.1 unit/ml) 80% growth inhibition was observed. TZT at a concentration of 10(-8) M did not affect the growth of Walker 256 cells. The combination of 10(-8) M TZT with CPDG1 (0.1 unit/ml), however, strongly inhibited cell growth. In experiments with rats bearing Walker 256 carcinosarcoma, the administration of CPDG1 (800 units/kg/day) from Day 1 to Day 6 resulted in no significant increase in life span. Administration of TZT in doses up to 0.05 mg/kg on Day 1 or that of DDMP up to 15 mg/kg on Days 1, 3, and 5 had no antitumor effects as measured by survival of the animals. However, CPDG1 (800 units/kg/day) from Day 1 to Day 6 in combination with TZT (0.05 mg/kg on Day 1) or DDMP (15 mg/kg on Days 1, 3, and 5) resulted in increases of 50 and 30%, respectively, in the survival of the tumor-bearing animals. These results demonstrate that CPDG1 enhances the antitumor effects of TZT or DDMP.
Reaction of glycosyl isothiocyanates (la, b or c) with acyl or aroyl hydrazine gave the corresponding glycosyl thiosemicarbazides, and which were treated with Ac2O-H3PO4 to yield 1,2,4-triazole glycosides. Similar treatment of la, b or c with amidino compounds gave glycosylisothiobiurets, followed by N-bromosuccinimide (NBS) oxidation to give 1,2,4-triazole glycosides. Treatment of glycosylisothiobiurets with triethyl orthoformate gave the corresponding s-triazine glycosides.
At room temperature tetrahydro-1,3-oxazine (THO) is converted into the very viscous 1,3,5-tris(3-hydroxypropyl)-hexahydro-1,3,5-triazine (THT) over several weeks. On heating to ca. 125 degrees C THO will be reformed from THT. The structure of THT was proven by mass-, 1H- and 13C-NMR spectra.
1. Phagocytic activity measured by means of the intravasal clearance of a soot dispersion in male NMRI-mice was increased six to ten days after whole-body X-irradiation (640 R) and decreased during the same period after i.v. administration of 2,4,6-triethyleneimino-s-triazine (TEM 2.0 mg/kg). 2. By means of 6-methyl-uracil food admixtures (200 to 400 ppm during 2 or 3 weeks) or by repeated intravenous injections of a N-methyl-D-glucosamine-6-methyluracil complex (62.5 to 250 mg/kg daily during five days), a significant augmentation of the phagocytic index being related to time and dosage was obtained in otherwise untreated mice. Comparable results were seen using cytidine and cytidine-s'-phosphate, whereas guanosine-5'-phosphate remained ineffective. 3. Whilst stimulating effects of 6-methyl-uracil or its N-methyl-D-glucosamine complex on X-irradiated mice were suspended, an increase up to supernormal values of the phagocytic index was produced by the pyrimidine base in animals treated with TEM. In accordance to this the survival rate of lethally X-irradiated mice (960 R) could not be increased; with animals given lethal TEM-doses, however, a significantly increased survival rate was obtained. 4. The present investigations as well as former biochemical analyses confirm the assumption that 6-methyluracil produces its regeneration effects, to some extent at least, by specific pathways influencing the reticuloendothelium. Different results from X-irradiated and TEM-treated mice are referring to the different points of attack of the two noxa.
EPR spectra of anion radicals were recorded as a result of chemical or enzymatic reduction at various pH of the pyrimido-triazine antibiotics. These anion radicals easily form superoxide radicals in the presence of oxygen. It is supposed that a higher selectivity of reumycin action is due to difference in the redox potentials of the neutral and ionized antibiotic forms. A possibility of enhance the reumycin potency may involve the pH lowering inside the tumor cells - for example, by glucose injections.
The synthesis of 2-substituted derivatives of 5H-1,3,4-thiadiazolo[3,2-a] [1,3,5]triazin-5-one, obtained from 5-substituted 2-amino-1,3,4-thiadiazoles is described. The structure of the new compounds is confirmed by U.V. and I.R. spectra and partly by mass spectrometry.
The biodegradation and utilization of the antiphytoviral substance 2,4-dioxohexahydro-1,3,5-triazine (DHT) by soil microorganisms was investigated. Mixed cultures of microorganisms deriving from different soils diminish in nutrient broth the content of DHT with increasing duration of culture. Microorganisms from an Egyptian garden soil fully degrade 10(-3) mol/1 DHT in a culture without additional aeration within 28 days. Also in deficient media the mixed microorganisms reduce the amount of DHT, reaching in nitrogen free nutrient solution even a degradation rate up to 12 mg DHT per liter and day. Pure cultures of Rhizobium leguminosarum, Proteus vulgaris, Saccharomyces cerevisiae and especially Agrobacterium radiobacter diminish the content of DHT in nitrogen free media, too. No such effect was detectable in cultures of four other species of soil bacteria. The DHT degradation by the microorganisms is connected with significant cell multiplication, e.g. A. radiobacter in shaking cultures with DHT as sole source of nitrogen shows a typical growth cycle with a lag-phase of 24 hours. The short persistence time of DHT in soils is concluded to be mainly due to biodegradation by microorganisms.