Showing papers on "Triazene published in 1984"

Antitumor imidazotetrazines. 1. Synthesis and chemistry of 8-carbamoyl-3-(2-chloroethyl)imidazo[5,1-d]-1,2,3,5-tetrazin-4(3 H)-one , a novel broad-spectrum antitumor agent.

Abstract: Interaction of 5-diazoimidazole-4-carboxamide and alkyl and aryl isocyanates in the dark affords 8-carbamoyl-3-substituted-imidazo[5,1-d]-1,2,3,5-tetrazin-4(3H)-on es. In cold methanol or ethanol, the 3-(2-chloroethyl) derivative 7a decomposes to afford 2-azahypoxanthine (14) and methyl and ethyl N-(2-chloroethyl)carbamates, respectively. Compound 7a has curative activity against L-1210 and P388 leukemia and may act as a prodrug modification of the acyclic triazene 5-[3-(2-chloroethyl)triazen-1-yl]imidazole-4-carboxamide (MCTIC), since it ring opens to form the triazene in aqueous sodium carbonate.

Triaziridines. Part III. Triaziridine, Azimine and Triazene: A SCF Study of the Energy and Structure of N3H3-Isomers

Abstract: The portions of the N3H3 singlet potential energy surface corresponding to triaziridines (1), azimines (2) and triazenes (3) have been calculated by ab initio SCF using 3-21G, 6-31G, and 6-31G** basis sets. Minima and transition states were located by force gradient geometry optimization. The most important computation results are: (1) Triaziridines (1): The configuration at the 3 N-atoms is pyramidal. There are 2 stereoisomers, 1a and 1b. The c,t-isomer 1a has less energy than the c,c-isomer 1b. The 2 stereoisomerizations by N-inversion hve rather high activation energies. The N,N bonds in 1 are longer and weaker (STO-3G estimation) than in hydrazine. The N-homocycle 1 exhibits less ring strain than the C-homocycle cyclopropane or three-membered heterocycles. (2) Azimine (2): All 6 Atoms are in the same plane. There are 3 stereoisomers, 2a, 2b, and 2c. The order of ground state energies is (Z,Z) < (E,Z) ≫ (E,E). The 2 N,N bond lengths correspond to multiplicity 1½. The electronic structure of 2 corresponds to a 1,3-dipole with almost equal delocalization of the 4 π-electrons over all 3 N-atoms. The negative net charge at the central N-atom is much less than that at the terminal N-atoms. Azimines should behave as π-donors in complexation with transition metals (3) Triazene (3): All 6 atoms are in the same plane. There are 2 stereoisomers, 3a and 3b. The order of ground-state energies is (E) < (Z). The stereoisomerization proceeds as pure N-inversion. N-Inversion has a high energy barrier inversion at N(1) is faster than at N(2). One of the N,N bond lengths is typical for a double, the other for a single bond. The electronic structure of triazene 3 entails rather localized π- and p-electron pairs at N(1),N(2) and at N(3). Triazenes should behave as p-donors in complexation with transition metals. (4) -N3H3-Isomers: The order of ground-state energies is 3 < 2 < 1. The energy differences between these constitutional isomers are much larger than between the stereoisomers of each. The [1,2]-H shifts for conversions of 2 to 3 and the [1,3]-H shift for tautomerization of 3 have relatively high activation energies; both shifts can be excluded as modes of thermal, unimolecular transformations.

New myocardial imaging agents: synthesis of 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid by decomposition of a 3,3-(1,5-pentanediyl)triazene precursor

Abstract: Methods have been developed for the rapid, regiospecific introduction of iodine into the para position of the terminal phenyl ring of 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid via the HI decomposition of a 3,3-(1,5-pentanediyl)triazene derivative of the p-amino substrate. The syntheses and physical properties of the triazene intermediate, 1-(4-(13(R,S)-methyl-14-carboxytetradecyl)phenyl)-3,3-(1,5-pentanediyl)triazene, and 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid are described. Radioiodinated methyl-branched long-chain fatty acids such as 15-(p-iodophenyl)-3(R,S)-methylpentadecanoic acid are of interest as myocardial imaging agents as a result of the pronounced uptake and prolonged heart retention, which appears to result from the inhibition of fatty acid metabolism. Iodine was introduced into the para position of the terminal phenyl ring by treatment of the triazene intermediate at 0-5/sup 0/C with HI which was generated by in situ treatment of sodium iodide in acetone with trifluoroacetic acid. The triazene intermediate decomposed to yield exclusively the p-iodophenyl product in good yield (> 50%). These results suggest that the decomposition of the 3,3-(1,5-pentanediyl)triazene derivative of terminal phenyl long-chain fatty acids is an attractive method for the preparation of high specific activity regiospecific radioiodinated agents. 22 references.

Studies of the mode of action of antitumor triazenes and triazines. 6. 1-Aryl-3-(hydroxymethyl)-3-methyltriazenes: synthesis, chemistry, and antitumor properties.

Abstract: 1-Aryl-3-(hydroxymethyl)-3-alkyltriazenes [ArN = NN(CH3)CH2OH] have been synthesized by diazonium coupling to the carbinolamine (RNHCH2OH), generated in situ from the alkylamine and formaldehyde mixtures. The (hydroxymethyl)triazene structure has been confirmed by IR, NMR, and mass spectral analysis and also by the preparation of a crystalline benzoate derivative. The mass spectra of the (hydroxymethyl)triazenes suggest that they fragment by loss of formaldehyde to give the methyltriazene, which is also the product of hydrolysis in solution. The degradation of the (hydroxymethyl)triazenes in solution has been followed by UV spectroscopy and by HPLC analysis, and the half-lives were determined under a variety of conditions. The half-lives of the corresponding methyl- and (hydroxymethyl)triazenes are very similar. Both methyl- and (hydroxymethyl)triazenes decompose on silica plates during TLC analysis to give products consistent with known diazo-migration reactions. The (hydroxymethyl)triazenes have pronounced antitumor activity against the TLX5 tumor in vivo; in vivo-in vitro bioassay experiments suggest that the (hydroxymethyl)triazenes exert their in vivo antitumor activity via the degradation product, the alkyltriazene.

Open-chain nitrogen compounds. Part VI. The formation of bis(1-aryl-3- methyltriazen-3-ylmethyl) methylamines in the reaction of diazonium ions with mixtures of formaldehyde and methylamine

Abstract: The synthesis of a series of N,N-bis(1-aryl-3-methyltriazen-3-ylmethyl) methylamines from coupling diazonium salts with mixtures of methylamine and formaldehyde is described. These novel bis-triazenes, or heptazanonadienes, have significant anti-tumour activity against the TLX5 lymphoma in mouse. The mechanism of formation of these triazenes is discussed with reference to the implication to the presumed equilibria taking place in the methylamine/formaldehyde solution. The formation of the bis-triazene is usually accompanied by the formation of a 3-hydroxymethyitriazene, and it has been shown that the hydroxymethyltriazene can be transformed into the bis-triazene. The proportions of the two products are strongly influenced by the relative amounts of methylamine and formaldehyde. Coupling the p-bromobenzenediazonium salt to a 1:1 methylamine/formaldehyde mixture affords mainly the bis-triazene, whereas a 1:50 mixture gives almost totally the hydroxymethyl triazene. These results suggest that the two triazen...

Silyl, Germyl, and Stannyl Derivatives of Azenes, NnHn: Part I. Derivatives of Diazene, N2H2

Abstract: Publisher Summary This chapter discusses the preparation and properties of silyl, germyl, and stannyl derivatives of some azenes, N n H n (n=2–5) It also discusses the preparation and properties of Group IV derivatives of diazene, Group IV derivatives of triazene, tetrazene, and pentazene The silyl derivatives of nitrogen are usually more stable thermally than the corresponding hydrogen derivatives Bis(trimethylsilyl)diazene (BSD), Me 3 Si–N=N–SiMe 3 , may be prepared easily by the oxidation of lithium tris(trimethylsily1)hydrazide with appropriate oxidizing agents The hydrolysis of other azosilanes and azogermanes is expected to be analogous to that of BSD To explain the thermolysis mechanism, the effects of reaction temperature, BSD concentration, and reaction medium on the yield of the thermolysis products have been investigated, and the nature of radical side products and the dependence of their yield on the reaction conditions have been studied BSD is exceedingly reactive, and the same is generally true for silyl and germyldiazenes The inner molecular orbitals, significant for chemical reactions of BSD, are the highest occupied n + and the lowest vacant π* molecular orbitals, which unlike the corresponding orbitals of azoalkanes lie energetically very high and low, respectively On this basis, silyl diazenes should be good ligands, acting as strong n donors and moderate π acceptors

Ruthenium(IV) in centrosymmetric RuX2N2O2 coordination: synthesis, structure, and redox properties of dihalobis(triazene 1-oxidato)ruthenium species

Abstract: Le complexe dichlorobis(ethyl-1-p-tolyl-3-triazene-oxydato-1) ruthenium cristallise dans le systeme monoclinique, groupe P2 1 /n. Affinement de sa structure jusqu'a R=0,055. La sphere de coordination est RuCl 2 N 2 O 2 avec l'atome metallique place au centre de symetrie

Ruthenium(IV) in centrosymmetric RuX2N2O2 coordination: synthesis, structure, and redox properties of dihalobis(triazene 1-oxidato)ruthenium species

Abstract: Le complexe dichlorobis(ethyl-1-p-tolyl-3-triazene-oxydato-1) ruthenium cristallise dans le systeme monoclinique, groupe P2 1 /n. Affinement de sa structure jusqu'a R=0,055. La sphere de coordination est RuCl 2 N 2 O 2 avec l'atome metallique place au centre de symetrie

Cationic triazene dyes and their use

Abstract: not available for EP0053751Abstract of corresponding document: US4432897The cationic triazene dyestuffs of the general formula (I) wherein B denotes alkylmercapto, arylmercapto or a radical of the formula R denotes hydrogen or an alkyl, alkenyl, acyl, cycloalkyl, aryl, aralkyl, amino, alkylamino, dialkylamino, arylamino, aralkylamino or heterocyclic radical and R1 denotes hydrogen or an alkyl, alkenyl or aralkyl radical, or R and R1 are bonded to a heterocyclic structure, R2 and R3 denote an alkyl, alkenyl, alkinyl or aralkyl radical, or one of the radicals R2 or R3 also denotes hydrogen, or R3 is bonded to the o-position of A, A denotes an aryl radical and An(-) denotes an anion, and wherein the cyclic and acyclic radicals can contain non-ionic substituents and/or a carboxyl group, can be used for dyeing and printing natural and synthetic materials.

Crystal and molecular structure of 3-methyl-1-p-tolyltriazene

Abstract: Crystals of the title compound have monoclinic symmetry with a= 8.196(1), b= 8.545(2), c= 13.163(2)A, β= 112.72(2)°, and space group P21/c. For 1 088 observed independent reflections collected on a four-circle diffractometer the R-factor reached 0.063 after full-matrix least-squares refinement. The triazene unit has a double bond between N(1)and N(2) with a hydrogen atom and a methyl group both carried by N(3). A 21–22° twist about the bond joining ring to triazene helps to relieve steric hindrance. Molecules are linked by N–H ⋯ N hydrogen bonding. The preference for the tautomeric form p-CH3·C6H4·NNH-CH3 in the solid state is consistent with the behaviour in solution, as determined by n.m.r. spectroscopy.

Ligand redistribution in triazene 1-oxide complexes: a voltammetric study

Abstract: Etudes par voltammetrie cyclique et par voltammetrie a impulsions differentielles des reactions des complexes des metaux de transition avec les derives a des triazene oxyde-1 abreges sous la forme M(RX) p avec M=Cu, p=2, M=Co, Fe, Ru et p=3; R=Et, Ph; X=OMe, Me, H, Cl, CO 2 Et, No 2

Studies of the mode of action of antitumor triazenes and triazines. 6. 1-aryl-3-(hydroxymethyl)-3-methyltriazenes: synthesis, chemistry, and antitumor properties

Abstract: 1-Aryl-3-(hydroxymethyl)-3-alkyltriazenes [ArN = NN(CH3)CH2OH] have been synthesized by diazonium coupling to the carbinolamine (RNHCH2OH), generated in situ from the alkylamine and formaldehyde mixtures. The (hydroxymethyl)triazene structure has been confirmed by IR, NMR, and mass spectral analysis and also by the preparation of a crystalline benzoate derivative. The mass spectra of the (hydroxymethyl)triazenes suggest that they fragment by loss of formaldehyde to give the methyltriazene, which is also the product of hydrolysis in solution. The degradation of the (hydroxymethyl)triazenes in solution has been followed by UV spectroscopy and by HPLC analysis, and the half-lives were determined under a variety of conditions. The half-lives of the corresponding methyl- and (hydroxymethyl)triazenes are very similar. Both methyl- and (hydroxymethyl)triazenes decompose on silica plates during TLC analysis to give products consistent with known diazo-migration reactions. The (hydroxymethyl)triazenes have pronounced antitumor activity against the TLX5 tumor in vivo; in vivo-in vitro bioassay experiments suggest that the (hydroxymethyl)triazenes exert their in vivo antitumor activity via the degradation product, the alkyltriazene.

Chemical and Biological Properties and Mode of Action of 8-Carbamoyl-3-(2-Chloroethyl)Imidazo [5,1-d]-1,2,3,5-Tetrazin-4(3H)-One, A Novel Broad Spectrum Antitumour Agent

Abstract: The title compound is synthesised by interaction of 5-diazoimidazole-4-carboxamide with 2-chloroethyl isocyanate in a variety of solvents at 20-60°C in the dark. It has curative activity against L1210 and P-388 leukaemia and also shows marked activity against a variety of other tumours, including LL, C88, B16 M5076, ADJ/PC6A and TLX/5 lymphoma. It also markedly inhibits metastasis observed with the LL tumour. Biochemical studies carried out recently at the University of Aston suggest a relation to the triazene type of antitumour agent, and chemical degradation studies to be described indicate that the compound may unusually be a pro-drug of the active but unstable 5[3-(2-chloroethyl)triazen-1-yl]imidazole-4-carboxamide (MCTIC).

Mechanism of azo coupling reactions. xxxiii. ph‐dependence and micromixing effects on the product distribution of couplings with 6‐amino‐4‐hydroxy‐2‐naphthalenesulfonic acid. evidence for n‐coupling of a naphthylamine derivative

Abstract: Azo coupling of 6-amino-4-hydroxy-2-naphthalenesulfonic acid (1) with 3-trifluoromethyl- and 4-nitrobenzenediazonium ion in relative highly concentrated aqueous alkaline solutions gave ratios of aminoazo to hydroxyazo compounds which are much higher than expected on the basis of the acid-base pre-equilibria of 1. These product ratios are disguised by effects of micromixing. In dilute solution (≤10−2 mol/l) product ratios and kinetics both correspond to the theory of acid-base pre-equilibria. A bisazo dye 10 was formed as a by-product in couplings with 3-trifluoromethylbenzediazonium ion, as expected for reactions with micromixing effects. In the reaction with benzenediazonium ions, the products of azo coupling of diazotized 1 with 1 (compound 8) and of the monoazo compound 8 with benzenediazonium ion (compound 9) were found. It is likely that diazotized 1 is formed by N-coupling of 1 with benzenediazonium ion, tautomeric rearrangement and protonation of the triazene to diazotized 1 and aniline. This seems to be the first case of N-coupling of a naphthylamine which was assumed to be capable of C-coupling only.

Chemistry of ruthenium. part 10. triazene 1-oxide complexes of bis(2,2′-bipyridine)ruthenium(ii) and -(iii). synthesis, spectra, and electrochemistry

Abstract: Mixed ruthenium complexes of type [Ru(bipy)2L]ClO4·H2O derived from 2,2′-bipyridine (bipy) and triazene 1-oxides, RN(O)N–NH–C6H4X-p(HL: R = Et or Ph; X = Me, H, Cl, CO2Et, or NO2) are described. In solution they display two quasi-reversible reductions due to electron transfer to co-ordinated bipy units. The RuIII–RuII couple occurs in the range 0.16–0.44 V versus s.c.e. The formal potential of this couple is linearly related to the Hammett constant of substituent X. The low-spin ruthenium(III) analogue, [Ru(bipy)2L]2+, is furnished by both coulometric and chemical oxidations. The energy of the ligand-to-metal charge-transfer band of [Ru(bipy)2L]2+ correlates linearly with the RuIII–RuII formal potential.