Browse
Submit Data
Databases
API
Help

Dataset Information

20 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

1,2,4,5-Tetrakis(tetramethylguanidino)-3,6-diethynyl-benzenes: Fluorescent Probes, Redox-Active Ligands and Strong Organic Electron Donors.

ABSTRACT: In this work, the change of reactivity induced by the introduction of two para-ethynyl substituents (CCSi(iPr)3 or CCH) to the organic electron-donor 1,2,4,5-tetrakis(tetramethylguanidino)-benzene is evaluated. The redox-properties and redox-state dependent fluorescence are evaluated, and dinuclear CuI and CuII complexes synthesized. The Lewis-acidic B(C6 F5 )3 substitutes the proton of the ethynyl -CCH groups to give new anionic -CCB(C6 F5 )3 - substituents, leading eventually to a novel dianionic strong electron donor in its diprotonated form. Its two-electron oxidation with dioxygen in the presence of a copper catalyst yields the first redox-active guanidine that is neutral (instead of cationic) in its oxidized form.

SUBMITTER: Wagner C

PROVIDER: S-EPMC7497081 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

1,2,4,5-Tetrakis(tetramethylguanidino)-3,6-diethynyl-benzenes: Fluorescent Probes, Redox-Active Ligands and Strong Organic Electron Donors.

Wagner Conrad C Kreis Franka F Popp Dennis D Hübner Olaf O Kaifer Elisabeth E Himmel Hans-Jörg HJ

Chemistry (Weinheim an der Bergstrasse, Germany) 20200710 45

In this work, the change of reactivity induced by the introduction of two para-ethynyl substituents (CCSi(iPr)3 or CCH) to the organic electron-donor 1,2,4,5-tetrakis(tetramethylguanidino)-benzene is evaluated. The redox-properties and redox-state dependent fluorescence are evaluated, and dinuclear CuI and CuII complexes synthesized. The Lewis-acidic B(C6 F5 )3 substitutes the proton of the ethynyl -CCH groups to give new anionic ...[more]

PMID: 32368816

Similar Datasets

1,2,5,6-Tetrakis(guanidino)-Naphthalenes: Electron Donors, Fluorescent Probes and Redox-Active Ligands.

Project description:New redox-active 1,2,5,6-tetrakis(guanidino)-naphthalene compounds, isolable and storable in the neutral and deep-green dicationic redox states and oxidisable further in two one-electron steps to the tetracations, are reported. Protonation switches on blue fluorescence, with the fluorescence intensity (quantum yield) increasing with the degree of protonation. Reactions with N-halogenosuccinimides or N-halogenophthalimides led to a series of new redox-active halogeno- and succinimido-/phthalimido-substituted derivatives. These highly selective reactions are proposed to proceed via the tri- or tetracationic state as the intermediate. The derivatives are oxidised reversibly at slightly higher potentials than that of the unsubstituted compounds to dications and further to tri- and tetracations. The integration of redox-active ligands in the transition-metal complexes shifts the redox potentials to higher values and also allows reversible oxidation in two potentially separated one-electron steps.

| S-EPMC7318682 | biostudies-literature

1,2,4,5-Tetra-methyl-3,6-diphenyl-1,2,4,5-tetra-aza-3,6-diphosphinane.

Project description:The title compound, C(16)H(22)N(4)P(2), crystallizes about a centre of symmetry, leading to a chair conformation of the heterocyclic ring as is commonly found for this type of compound.

| S-EPMC2960921 | biostudies-literature

Genetically encoded fluorescent redox probes.

Project description:Redox processes are involved in almost every cell of the body as a consequence of aerobic life. In the past decades, redox biology has been increasingly recognized as one of the key themes in cell signaling. The progress has been accelerated by development of fluorescent probes that can monitor redox conditions and dynamics in cells and cell compartments. This short paper focuses on fluorescent redox probes that are genetically encoded, and discusses their properties, molecular mechanism, advantages and pitfalls. Our recent work on reaction-based encoded probes that are responsive to particular redox signaling molecules is also reviewed. Future challenges and directions are also commented.

| S-EPMC3871076 | biostudies-literature

4,4'-(1,2,4,5-Tetra-zine-3,6-di-yl)dibenzo-nitrile.

Project description:Mol-ecules of the title compound, C(16)H(8)N(6), lie on crystallographic inversion centres. A dihedral angle of 16.1 (1)° is formed between the central tetra-zine ring and the plane of each cyano-phenyl group. The mol-ecules form stacks along [100] with a perpendicular inter-planar separation of 3.25 (1) Å. C-H⋯N inter-actions are formed between mol-ecules in neighbouring stacks.

| S-EPMC2968976 | biostudies-literature

1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetra-zine.

Project description:In the title compound, C(21)H(16)N(4)O, the central tetra-zine ring adopts an unsymmetrical boat conformation with the two N atoms as the bow and stern. The crystal packing is stabilized by inter-molecular N-H-O hydrogen bonds.

| S-EPMC2983408 | biostudies-literature

Heterotrimetallic Assemblies with 1,2,4,5-Tetrakis(diphenylphosphino)benzene Bridges: Constructs for Controlling the Separation and Spatial Orientation of Redox-Active Metallodithiolene Groups.

Project description:Metallodithiolene complexes of the type [(R2C2S2)M(η2-tpbz)] [R = CN, Ph, or p-anisyl; M = Ni2+, Pd2+, or Pt2+; tpbz = 1,2,4,5-tetrakis(diphenylphosphino)benzene] chelate transition metals ions to form trimetallic arrays [[(R2C2S2)M(tpbz)]2M']n+, where M' is square planar Pt2+, tetrahedral Cu+, Ag+, or Au+, or octahedral {ReBr(CO)}/{Re(CO)2}+. Forcing conditions (190 °C reflux in decalin, 72 h) are demanded for the Re+ compounds. With third-row metals at the nexus, the compounds are stable to air. Twelve members of the set have been characterized by X-ray diffraction and reveal dithiolene centroid-centroid distances ranging from 22.4 to 24.0 Å. Folding around each tpbz intrachelate P···P axis such that the MP2/M'P2 planes meet the tpbz P2C6P2 mean plane at non-zero values gives rise to core topologies that appear "S-like" or herringbone-like for M' = Pt2+ or {ReBr(CO)}/{Re(CO)2}+. Calculations reveal that departure from idealized D2h/D2d/C2v symmetries is induced by steric crowding between Ph groups and that dynamic, fluxional behavior is pertinent to the solution phase because multiple, lower-symmetry minima of comparable energy exist. Spectroscopically, the formation of the trimetallic arrays is marked by a shift of the open end 31P nuclear magnetic resonance signal from approximately -14.5 ppm to approximately +41, approximately +20.5, and approximately +28.5 ppm for M' = Pt2+, Au+, and {ReBr(CO)}/{Re(CO)2}+, respectively. Electrochemically, dithiolene-based oxidations are observed for the R = Ph and M' = Pt2+ or Au+ compounds but at potentials that are anodically shifted relative to charge-neutral [[(R2C2S2)M]2(μ-tpbz)]. The compounds reported clarify the possibilities for the synthesis of assemblies in which weakly coupled spins may be created in their modular (R2C2S2)M and M' parts.

| S-EPMC9644372 | biostudies-literature

3,6-Substituted-1,2,4,5-tetrazines: tuning reaction rates for staged labeling applications.

Project description:Cycloaddition reactions involving tetrazines have proven to be powerful bioorthogonal tools for various applications. Conceivably, sequential and selective labeling using tetrazine-based reactions can be achieved by tuning the reaction rate. By varying the substituents on tetrazines, cycloaddition rate variations of over 200 fold have been achieved with the same dienophile. Upon coupling with different dienophiles, such as norbornene, the reaction rate difference can be over 14,000 fold. These substituted tetrazines can be very useful for selective labeling under different conditions.

| S-EPMC4149905 | biostudies-literature

3,3,6,6-Tetrakis-(hydroxy-meth-yl)-1,2,4,5-tetra-zinane tetra-hydrate.

Project description:In the title compound, C(6)H(16)N(4)O(4)·4H(2)O, the tetra-zinane mol-ecule lies across an inversion centre. The tetra-zinane ring adopts a chair conformation, and all imino H atoms occupy axial positions. In the crystal, adjacent mol-ecules are linked through O-H?O, O-H?N and N-H?O hydrogen bonds with water mol-ecules generating a three-dimensional network.

| S-EPMC2971896 | biostudies-other

N(1),N(4),3,6-Tetra-methyl-1,2,4,5-tetra-zine-1,4-dicarboxamide.

Project description:The asymmetric unit of the title compound, C(8)H(14)N(6)O(2), contains two independent mol-ecules. In one mol-ecule, the amide-substituted N atoms of the tetra-zine ring deviate from the plane [maximum deviation = 0.028?(1)?Å] through the four other atoms in the ring by 0.350?(2) and 0.344?(2)?Å, forming a boat conformation, and the mean planes of the two carboxamide groups form dihedral angles of 10.46?(13) and 20.41?(12)° with the four approximtely planar atoms in the tetra-zine ring. In the other mol-ecule, the amide-substituted N atoms of the tetra-zine ring deviate from the plane [maximum deviation = 0.033?(1)?Å] through the four other atoms in the ring by 0.324?(2) and 0.307?(2)?Å, forming a boat conformation, and the mean planes of the two carboxamide groups form dihedral angles of 14.66?(11) and 17.08?(10)° with the four approximately planar atoms of the tetra-zine ring. In the crystal, N-H?O hydrogen bonds connect mol-ecules to form a two-dimensional network parallel to (1-1-1). Intra-molecular N-H?N hydrogen bonds are observed.

| S-EPMC3379411 | biostudies-literature

Self-Immolative Thiocarbamates Provide Access to Triggered H2S Donors and Analyte Replacement Fluorescent Probes.

Project description:Hydrogen sulfide (H2S) is an important biological signaling molecule, and chemical tools for H2S delivery and detection have emerged as important investigative methods. Key challenges in these fields include developing donors that are triggered to release H2S in response to stimuli and developing probes that do not irreversibly consume H2S. Here we report a new strategy for H2S donation based on self-immolation of benzyl thiocarbamates to release carbonyl sulfide, which is rapidly converted to H2S by carbonic anhydrase. We leverage this chemistry to develop easily modifiable donors that can be triggered to release H2S. We also demonstrate that this approach can be coupled with common H2S-sensing motifs to generate scaffolds which, upon reaction with H2S, generate a fluorescence response and also release caged H2S, thus addressing challenges of analyte homeostasis in reaction-based probes.

| S-EPMC4911618 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data