Characterization of a Perhydro-5,6-di(methylene)-2,4-dioxopyrimidine Intermediate and Its Cycloaddition Reactions Leading to Quinazoline Derivatives

The SNS+ cation (in SNSAsF6) underwent symmetry-allowed concerted cycloadditions with the aryl nitriles RCN (R = 2,5-Me2C6H3, Ph, p-O2NC6H4, and 3,5-(O2N)2C6H3) and diphenylacetylene. The cycloadducts [Formula: see text] (R = 2,5-Me2C6H3, Ph, p-O2NC6H4, and 3,5-(O2N)2C6H3) and Ph [Formula: see text] were characterized by elemental analyses and IR and NMR (1H, 13C, 14N) spectroscopies. The reduction of [Formula: see text] gave the corresponding 1,3,2,4-dithiadiazoles [Formula: see text], which in turn rearranged to the corresponding 1,2,3,5-dithiadiazoles [Formula: see text]. The rate of this rearrangement was correlated with the ionization potentials of the corresponding nitriles. The radicals [Formula: see text] (R = Ph, p-O2NC6H4) were isolated as pure compounds, and characterized by mass spectrometry, IR, FT-Raman, and ESR spectroscopies. The reduction of [Formula: see text] led to neutral radical [Formula: see text], which is stable in solution up to ca. 0.5 M, but decomposes at higher concentrations.

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Synthesis and Spectral Characterization of 4,7-Dichloro-6-nitroquinazoline

Molbank ◽

10.3390/m1134 ◽

2020 ◽

Vol 2020 (2) ◽

pp. M1134 ◽

Cited By ~ 1

Author(s):

Thi Ngoc Nguyen ◽

Thi Huong Tran ◽

Nguyet Suong Huyen Dao ◽

Van Giang Nguyen ◽

Dinh Luyen Nguyen ◽

...

Keyword(s):

Kinase Inhibitor ◽

Therapeutic Potential ◽

Locally Advanced ◽

Intermediate Compound ◽

Chlorobenzoic Acid ◽

Ft Ir ◽

Important Intermediate ◽

Quinazoline Derivatives ◽

First Time

Afatinib is a 4-anilinoquinazoline tyrosine kinase inhibitor (TKI) in the form of a dimaleate salt which is indicated for the treatment of locally advanced or metastatic non-small cell lung cancer (NSCLC). The most scalable route for the synthesis of this drug was reported in two Boehringer Ingelheim patents, in which the title compound, 4,7-dichloro-6-nitroquinazoline (IV), is an important intermediate. Compound IV is also present in a number of synthetic pathways for various 4,7-disubstituted quinazoline derivatives displaying high therapeutic potential. However, no detailed characterization of this popular compound has been reported, possibly due to its high instability. In this paper, IV was prepared in an overall yield of 56.1% by a 3-step process (condensation, nitration, and chlorination) from 2-amino-4-chlorobenzoic acid (I). The target compound has been for the first time fully characterized by melting point, mass-spectrometry, FT-IR, 1H-NMR and 13C-NMR spectroscopies.

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Synthesis and Characterization of Palladium(II) Complexes with Substituted Dihydrobenzoimidazo Quinazoline Derivatives

Mapana Journal of Sciences ◽

10.12723/mjs.29.1 ◽

2017 ◽

Vol 13 (2) ◽

pp. 1-15

Author(s):

Rita Bhattacharjee Virupaiah Gayathri

Keyword(s):

Metal Ion ◽

Synthesis And Characterization ◽

Planar Geometry ◽

Conductivity Measurements ◽

Spectral Techniques ◽

Mass Spectral ◽

Square Planar ◽

Elemental Analyses ◽

Quinazoline Derivatives

A series of palladium(II) halo complexes of the types [PdX 2 L 2 ].nH 2 O {n = 0, X = Cl, L = L 2 , L 4 and L 5 ; X = Br, L = L 2 ; n = 1, X = Cl, L = L 1 and L 3 } and Pd 2 X 4 L 3 [X = Br, L = L 1 , L 3 , L 4 and L 5 ] were prepared where L is 6-R-5,6- dihydrobenzoimidazo quinazoline (R-Diq; where R = ethyl: L 1 / n or i-propyl: L 2 , L 3 / n or i-butyl: L 4 , L 5 ) and characterized by elemental analyses, conductivity measurements, TGA, infrared, electronic, NMR and mass spectral techniques. Based on these studies monomeric/dimeric structure with a square planar geometry around the metal ion was proposed for all the complexes. Some of the complexes were investigated for anti-microbial activity.

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