Synthesis of N-Quinonyl Carbamates via 2-Chloro-3-isocyanato-1,4-naphthoquinone

Bittner, Shmuel; Temtsin, Galina; Sasson, Yoel

doi:10.1055/s-2000-6318

Cited by 12 publications

(4 citation statements)

References 6 publications

(6 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The electrochemical study of bis‐ or diquinones is scarce [17] . The present work extends the previous electrochemical study of ω ‐ N ‐quinonyl amino acids to a new class of partly‐conjugated diquinonyl amines (both symmetric and non‐symmetric) [1d,e,15] that can contribute to the library of biologically active molecules. They contain an internal proton source stemming from the acidic nature of the ′NH′ group that links together two quinonyl moieties (Scheme 4).…”

Section: Electrochemical Properties Of Diquinonyl Derivatives Involving An Internal Proton Sourcesupporting

confidence: 60%

Electrochemistry of Quinones with Respect to their Role in Biomedical Chemistry

Krayz

Bittner

Dhiman

et al. 2021

The Chemical Record

Self Cite

View full text Add to dashboard Cite

Quinones are ubiquitous in nature and form one of the largest class of antitumor agents approved for clinical use. They are known to be efficient in inhibiting cancer cells growth. Under physiological conditions they can undergo non‐enzymatic one‐electron reduction to give the moderately toxic species of semiquinone radical‐anion. Thus, electrochemical study of quinones might provide a basic knowledge on semi‐quinone radicals formation in both in vivo and in vitro under different media. Several processes are outlined briefly and discussed in the present article. Previously we investigated the electrochemical and spectral properties of ω‐N‐quinonyl amino acids. Such quinone‐bearing peptides are known to be cytotoxic and of potential clinical significance. We were able to prove that the ω‐amino quinonyl compounds are very effective in producing stable semiquinone radicals. Moreover, a direct relation was found between the first reduction potentials of the quinonyl moiety and their reactivity towards the ω‐amino acids. In order to increase our knowledge of such amino quinonyl compounds and enlarge the arsenal of such cytotoxic compounds, a series of N,N‐diquinonyl amines (1–6) bearing an internal proton (stems from the NH moiety) were synthesized. Their electron‐transfer capabilities were probed by cyclic voltammetry measurements, in dichloromethane. It was found that the acidic NH group linking the two quinonyl moieties undergoes an initial electrochemical reduction step and generates a nitride anion. This step is followed by further reductions to yield quasi‐stable semiquinone radicals and polyanions, Since these acidic diquinones (1–6) serve also as a source of internal proton donors even in non‐polar medium, they might cause protonation of basic radical‐anions and polyanion intermediates during the various electrochemical stages. The processes are demonstrated and discussed by analyzing different mechanistic schemes. The successful generation of relatively stable semiquinone radicals is a prerequisite for the manifestation of site directed antitumor activity by these bis‐quinonyl amino derivatives. Based on the values of their redox potentials some of them could be promising candidates for clinical development.

show abstract

Section: Electrochemical Properties Of Diquinonyl Derivatives Involving An Internal Proton Sourcesupporting

confidence: 60%

Electrochemistry of Quinones with Respect to their Role in Biomedical Chemistry

Krayz

Bittner

Dhiman

et al. 2021

The Chemical Record

Self Cite

View full text Add to dashboard Cite

show abstract

“…The reaction of potassium cyanate with 2,3-dichloro-1,4-naphthoquinone (1) in DMSO or DMF afforded the unstable naphthoquinonyl isocyanate (426), for stabilization alcohol was added which gave product 427 in 67-90% yields and byproducts 428 and 429. The naphthoquinonyl isocyanate (426) was proceeds via Michael addition of the isocyanate anion with the quinone (1) followed by KCl elimination and rapid reaction with alcohol lead to the formation of carbamate (427); Scheme 91 [131]. Dumur et al reported the synthesis of tetrathiafulvalene (433) from 432 in seven steps; scheme 93 [133].…”

Section: Miscellaneous Reactions Of 23-dichloro-14-naphthoquinonementioning

confidence: 99%

Synthetic and Biological Utility of 2,3-Dichloro-1,4-Naphthoquinone: A Review

Maurya

2020

Int. J. Res. Granthaalayah

View full text Add to dashboard Cite

2,3-Dichloro-1,4-naphthoquinones (dichlone) have attracted considerable attention for the construction of biologically active tricyclic and tetracyclic 1,4-quinones and other derivatives. A diversified reaction of 2,3-dichloro-1,4-naphthoquinones such as cycloaddition, condensation, photo induced and nucleophilic substitution reactions with suitable nucleophiles viz. carbon, nitrogen, oxygen, sulfur, selenium etc have been explored. Various synthesized compounds have also explored for their biological activity such as antifungal, antibacterial, anticancer, antiplatlet, anti-inflamentry, anti-allergic and anti HIV. This review describes the chemistry and biological activity of compounds synthesized from 2,3-dichloro-1,4-naphthoquinones during the last three decades.

show abstract

“…The chemistry of quinones is of considerable interest because this class of compounds includes many natural products and numerous important synthetic products . Addition of nitrogen nucleophiles to benzoquinone and naphthoquinone represents a common synthetic route to many fused heterocyclic rings, which have been used as synthetic intermediates in medicinal chemistry and for dyestuffs .…”

Section: Introductionmentioning

confidence: 99%