Structure-activity Relationship of Herbicidal 2,3-Dicyano-5-Substituted Pyrazines

Nakamura, Akira; Ataka, Toshiei; Segawa, Hirozo; Takeuchi, Yoshinori; Takematsu, Tetsuo

doi:10.1080/00021369.1983.10865823

Cited by 9 publications

(8 citation statements)

References 5 publications

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“…Optimization of the conditions for the Suzuki–Miyaura cross‐coupling reactions is summarized in Table . Synthon 13 was prepared by condensation of glyoxylic acid with diaminomaleonitrile (DAMN) in acetic acid and subsequent chlorination with POCl 3 according to a previously published procedure . Similarly, compound 14 was obtained as a product of the condensation of DAMN with 2‐(4‐iodophenyl)‐2‐oxoacetaldehyde, which was prepared by partial oxidation of 4‐iodoacetophenone with selenium dioxide.…”

Section: Resultsmentioning

confidence: 99%

OFF‐ON‐OFF Red‐Emitting Fluorescent Indicators for a Narrow pH Window

Cidlina

Miletín

Fathi-Rasekh

et al. 2016

Chemistry A European J

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A unique combination of two independent mechanisms of fluorescence quenching, namely intramolecular charge transfer (ICT) from a peripheral donor and protonation of azomethine nitrogen atoms in zinc tetrapyrazinoporphyrazines (TPyzPz), provides a new possibility for sensing pH in a specific range. The pH selectivity was controlled by the different basicities of the donor for ICT (dimethylaminoaryl), which was connected to the macrocycle by π-extended linkers of different lengths. ICT and protonation have been studied in detail by photophysical, spectral (UV/Vis and MCD spectra), and electrochemical measurements, and further supported by theoretical calculations (DFT, TDDFT). The pH-sensing properties of the TPyzPzs have been investigated in THF and in water after anchoring the TPyzPzs to liposomes. The salient pK values were around 1.3 (azomethine nitrogen) and 2.29-4.76 (donor for ICT). The lead indicators (sensing over a pH range of 1.0-2.5) with fairly steep sensing profiles exhibited increases in fluorescence between the OFF/ON states of more than 20-fold and strong absorption in the red region (Q-band maximum >650 nm, ϵ≈2×10 m cm ).

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Section: Resultsmentioning

confidence: 99%

OFF‐ON‐OFF Red‐Emitting Fluorescent Indicators for a Narrow pH Window

Cidlina

Miletín

Fathi-Rasekh

et al. 2016

Chemistry A European J

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“…Thanks to this variability of peripheral substitution this compound is a very interesting starting material for the preparation of macrocycles with variable properties (e.g., spectral properties, solubility, hydrophilicity and hydrophobicity, the amount of peripheral charges). Moreover, substituted heterocycles containing the pyrazine-2,3-dicar- bonitrile core have also been investigated for their herbicidal [26,27] and antineoplastic [28,29] activities. Compound 3 is a promising starting material for derivatives of quinoxalinedicarbonitriles, investigated also for their potential in these interesting applications.…”

Section: Synthesis and Characterizationmentioning

confidence: 99%

Synthesis, Separation and UV/Vis Spectroscopy of Pyrazino‐quinoxalino‐porphyrazine Macrocycles

Musil¹,

Zimčík²,

Miletín³

et al. 2007

Eur J Org Chem

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Unsymmetrical metal-free and zinc complexes of pyrazinoquinoxalino-porphyrazines (PQP) bearing eight diethylamino groups have been synthesized by statistical tetramerization of 2,3-bis(diethylamino)quinoxaline-6,7-dicarbonitrile and 5,6-bis(diethylamino)pyrazine-2,3-dicarbonitrile in lithium butanolate. For this purpose, a new heteroatom-substituted quinoxaline precursor, 2,3-dichloro-6,7-dicarbonitrile, was prepared and characterized. It is a flexible starting material for new building blocks of quinoxaline-6,7-dicarbonitrile derivatives. All the PQPs (including adjacent and opposite isomers) from the statistical mixture were detected and separated by column chromatography on silica and characterized

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“…While Diquat's activity consists mostly in its interaction with the photosystem I and via subsequent formation of free radicals, the two latter were shown to inhibit acetylCoA carboxylase [37,38]. Nakamura et al [39] synthesized sixty-six 2,3-dicyano-5-substituted pyrazines and measured their herbicidal activities against barnyard grass in pot tests to clarify the relationship between chemical structure and activity. The activity of 59 derivatives showed parabolic dependence on the hydrophobic substituent parameter at the 5-position of the pyrazine ring, indicating that the compounds should pass through a number of lipoidal-aqueous interfaces to reach a critical site for biological activity.…”

Section: Introductionmentioning

confidence: 99%

Thermal, spectroscopic (IR, Raman, NMR) and theoretical (DFT) studies of alkali metal complexes with pyrazinecarboxylate and 2,3-pyrazinedicarboxylate ligands

Świderski

Lewandowska

Świsłocka

et al. 2016

J Therm Anal Calorim

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Pyrazinecarboxylic acid and its derivatives show biological properties (inter alia antimicrobial and antifungal). In the frame of this work, the salts of 2-pyrazinecarboxylic and 2,3-pyrazinedicarboxylic acids with alkali metal cations were synthesized as well as the spectroscopic (IR, Raman, NMR), theoretical [density functional theory (DFT)] and thermogravimetric studies of obtained compounds were done. The FT-IR and FT-Raman spectra of alkali metal 2-pyrazinecarboxylates and 2,3-pyrazinedicarboxylates were recorded and analyzed in the region of 4000-400 cm -1 . 1 H NMR and 13 C NMR spectra of analyzed compounds have been registered and assigned. The electronic charge distribution for the studied acids and their salts with lithium, sodium and potassium was calculated. All the calculations were done in the frame of p) basis set. The thermal decomposition of the analyzed compounds was done.

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Structure-activity Relationship of Herbicidal 2,3-Dicyano-5-Substituted Pyrazines

Cited by 9 publications

References 5 publications

OFF‐ON‐OFF Red‐Emitting Fluorescent Indicators for a Narrow pH Window

OFF‐ON‐OFF Red‐Emitting Fluorescent Indicators for a Narrow pH Window

Synthesis, Separation and UV/Vis Spectroscopy of Pyrazino‐quinoxalino‐porphyrazine Macrocycles

Thermal, spectroscopic (IR, Raman, NMR) and theoretical (DFT) studies of alkali metal complexes with pyrazinecarboxylate and 2,3-pyrazinedicarboxylate ligands

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