Synthesis and characterization of a highly fluorescent benzofuran dimer derived from estradiol

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Synthesis and characterization of a highly fluorescent benzofuran dimer derived from estradiol

A steroid dimer bearing the 1,4-di(benzofuran-2-yl)benzene moiety obtained from estradiol showed an intense blue fluorescence band between 350 and 550 nm with a 18-fold-increased quantum yield compared with that of its synthetic precursor.


Abstract

Pd-catalyzed cyclization of a fluorescent dimer in which two cores of the potent estrogenic estradiol are bridged by the 1,4-diethynil benzene moiety led to a steroid dimer bearing the 1,4-di(benzofuran-2-yl)benzene. The obtained compound showed an intense blue fluorescence characterized by a broad emission band between 350 and 550 nm, with four maxima at 384, 403, 435, and 456 nm. The benzofuran dimer showed an 18-fold increased quantum yield compared with that of its synthetic precursor.

Application of the aza‐Wittig reaction for efficient synthesis of diversely substituted benzo[f]Chromeno[2,3‐d]pyrimidine and benzo[f]chromeno[2,3‐d][1,2,4]triazolopyrimidine derivatives

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Application of the aza-Wittig reaction for efficient synthesis of diversely substituted benzo[f]Chromeno[2,3-d]pyrimidine and benzo[f]chromeno[2,3-d][1,2,4]triazolopyrimidine derivatives

An effective iminophosphorane mediates the synthesis of a fused ring system with potent anticancer relevance via the Aza-Wittig reaction.


Abstract

An efficient synthesis of novel benzo[f]Chromeno[2,3-d]pyrimidine and unknown benzo[f]chromeno[2,3-d][1,2,4]triazolopyrimidine derivatives is described utilizing ethyl-2-amino-4-phenyl-4H-benzo[f]chromene-3-carboxylate as precursor via aza-Wittig reaction. The process proved to be simple, high-yielding, and efficient.

1,3‐Dipolar Cycloaddition of Polycyclic Aromatic Azomethine Ylides and Alkynylbenziodoxoles for Synthesis of Functional Dibenzoullazines

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1,3-Dipolar Cycloaddition of Polycyclic Aromatic Azomethine Ylides and Alkynylbenziodoxoles for Synthesis of Functional Dibenzoullazines†

A new family of dibenzoullazine derivatives was synthesized through 1,3-dipolar cycloaddition of polycyclic aromatic azomethine ylides with alkynylbenziodoxoles followed by oxidation. The benziodoxole moiety in the resulting products was used as a versatile linchpin for the synthesis of structurally diverse functional dibenzoullazines that are difficult to access by other synthetic methods.


Comprehensive Summary

A new family of dibenzoullazine derivatives was synthesized through 1,3-dipolar cycloaddition of polycyclic aromatic azomethine ylides with alkynylbenziodoxoles followed by oxidation. The benziodoxole moiety in the resulting products was used as a versatile linchpin for the synthesis of structurally diverse functional dibenzoullazines that are difficult to access by other synthetic methods.

Direct Analysis of Whole Blood by a Disposable Monolithic Column Mass Spectrometry Analysis Kit

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Direct Analysis of Whole Blood by a Disposable Monolithic Column Mass Spectrometry Analysis Kit†

A disposable monolithic column mass spectrometry analysis kit was developed for direct whole blood analysis. The monolithic column can clean whole blood matrix in 30 s as well as avoid analyte exposure to oxygen, moisture and sunlight for sample storage. This MS kit has been successfully applied to the quantitative analysis of procainamide hydrochloride in 2 μL rat blood, proving it a cost-effective and powerful tool for in vitro diagnostics in the future.


Comprehensive Summary

A monolithic column-based mass spectrometry (MS) analysis kit was prepared for whole blood analysis with MS. The kit is disposable and can be used for purification, storage, transportation and direct analysis of whole blood. The kit mainly consists of a capillary for quantitative microsampling, a cation exchange monolithic column for purification and storage, and a syringe for loading sample. This kit is very friendly to various users that one can easily siphon the blood in the kit followed by rapid clean-up. We established a quantitative method using the kit with a limit detection as low as 0.33 nmol/L, and achieved more than five orders of magnitude enhancement in sensitivity compared to direct nanoelectrospray ionization MS analysis. The column can avoid analyte exposure to environment, which helps the storage of the sample for laboratory analysis. The relative standard deviation of immediate blood analysis and storage blood analysis within 10 d was less than 10%. This method has been successfully applied to the quantitative analysis of procainamide hydrochloride in 2 μL rat blood. These results indicate that this disposable kit does have the potential to achieve highly sensitive quantitative MS analysis in biological samples, which is expected to become a cost-effective and powerful tool for in vitro diagnostics.

Ru(II)‐Catalyzed ortho C—H Allylation of N‐Aryl‐7‐azaindoles with 2‐Methylidene Cyclic Carbonate

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Ru(II)-Catalyzed ortho C—H Allylation of N-Aryl-7-azaindoles with 2-Methylidene Cyclic Carbonate

We used Ru(II)-catalyst to perform ortho C—H allylation of N-aryl-7-azaindole with 2-methylenecyclic carbonate. The range of reactions is quite wide, and reactions can also be carried out on other heterocyclic compounds, and different carbonates can be used.


Comprehensive Summary

A Ru(II)-catalyzed ortho allylation reaction of N-aryl-7-azaindole with readily available 2-methylidene cyclic carbonate has been developed. This reaction is an effective pathway for synthesizing 7-azaindole derivatives with a wide scope of substrates and high yields. In addition, the method can be extended to the allylation of other heterocyclic compounds and several cyclic carbonates, highlighting the practicality of this strategy for synthesis.