Ahmed M. Fouda

Synthesis, characterization and density functional theory investigations of the electronic, photophysical and charge transfer properties of donor-bridge-acceptor triaminopyrazolo[1,5-a]pyrimidine dyes.

We have synthesized multifunctional dyes 3-(4-methyl-phenylazo)-6-(4-nitro-phenylazo)-2,5,7-triaminopyrazolo[1,5-a]pyrimidine (4a) and 3-(4-methyl-phenylazo)-6-(4-acetyl-phenylazo)-2,5,7-triaminopyrazolo[1,5-a]pyrimidine (4b), then characterized by IR, (1)H NMR and (13)C NMR techniques. The ground state geometries have been computed by using density functional theory at B3LYP/6-31G(*) level of theory. The absorption spectra have been calculated by using time dependent density functional theory with and without solvent. The highest occupied molecular orbitals (HOMOs) and lowest unoccupied molecular orbitals (LUMOs) are delocalized and localized on throughout the backbone, respectively. Solvent also play important role towards elevating the dipole moment. Significant red shift in absorption wavelengths have been observed in methanol compared to without solvent. We discussed the electron injection, electronic coupling constant and light harvesting efficiency.

Studies on the synthesis, in vitro antitumor activity of 4H-benzo[h]chromene, 7H-benzo[h]chromene[2,3-d]pyrimidine derivatives and structure–activity relationships of the 2-,3- and 2,3-positions

Some 4H-benzo[h]chromene and 7H-benzo[h]chromeno[2,3-d]pyrimidine derivatives were prepared as potential cytotoxic agents. The in vitro cytotoxic activity of the synthesized compounds was investigated in comparison with the well-known anticancer standard drugs Vinblastine, Colchicine, and Doxorubicin using MTT colorimetric assay. It was found that compounds 23, 15, 20, and 21 showed the highest anticancer activity against the three tumor cell lines MCF-7, HCT, and HepG-2, compared with Vinblastine and Colchicine, while compound 23 was the most active against HepG-2 as compared with Doxorubicin. We explored the SAR of 4H-benzo[h]chromenes with modification at the 2-,3- positions and 7H-benzo[h]chromeno[2,3-d]pyrimidine at 2,3-positions. The structure–activity relationship (SAR) study revealed that the antitumor activity on 4H-benzo[h]chromene and 7H-benzo[h]chromeno[2,3-d]pyrimidine derivatives were significantly affected by the lipophilicity (hydrophobic or hydrophilic), of the substituent at 2-,3- and 2,3-positions. Structures of these compounds were established on the basis of spectral data, IR, 1H NMR, 13C NMR, 13C NMR-DEPT, and MS data.

Synthesis, antitumor activity of 2-amino-4H-benzo[h]chromene derivatives, and structure–activity relationships of the 3- and 4-positions

Several 2-amino-4H-benzo[h]chromenes (3a–i) and (5a–h) were obtained by reaction of 4-chloro-1-naphthol (1) with α-cyanocinnamonitrile (2a–i) or ethyl α-cyanocinnamate derivatives (4a–h), respectively. Structures of these compounds were established on the basis of spectral data. The antitumor activity of the synthesized compounds was investigated in comparison with Vinblastine, Colchicine, and Doxorubicin well-known anticancer drugs, using MTT colorimetric assay. Among them, the compounds 5e, 3c, 5f, b, d, 3d, 5c, a were the most active against MCF-7, 5a against HCT-116 and 5a, 3e, a against HepG-2 as compared with the standard drug Vinblastine, while the compounds 5e, 3c, 5f, b, d, 3d, 5c, a, h, 3i, g, a, e were the most active against MCF-7, 5a, c, e, f, b, 3e, c, g, b, 5d, h, 3d, i, 5g against HCT-116, 5a, 3e, a, 5e, 3c, 5d, c, f, 3b, 5g, 3g, 5h against HepG-2 as compared with the standard drug Colchicine. The structure–activity relationships of the 3- and 4-positions were discussed.

Synthesis and antitumor activities of certain novel 2-amino-9-(4-halostyryl)-4H-pyrano[3,2-h]quinoline derivatives

A series of (E) 4H-pyrano[3,2-h]quinoline-3-carbonitrile (5a–f) and (E) ethyl 4H-pyrano[3,2-h]quinoline-3-carboxylate (6a–f) derivatives were synthesized by interaction of (E) 2-(4-chloro/bromo/fluorostyryl)-8-hydroxyquinoline (3a–c) with α-cyano-p-chloro/bromocinnamonitriles (4a,b) and ethyl α-cyano-p-chloro/bromocinnamates (4c,d), respectively. Structures of these compounds were established on the basis of IR, 1H NMR, 13C NMR, 13C NMR–DEPT, 13C NMR–APT, and MS data. The new compounds were evaluated for antitumor activities against three different human tumor cell lines MCF-7, HCT, and HepG-2. The results of antitumor evaluation revealed that compounds 5a,d and 6a,c,d inhibited the growth of cancer cells compared to Vinblastine. The structure–activity relationships were discussed.Graphical abstract

Synthesis of several 4H-chromene derivatives of expected antitumor activity

Multi-component reactions for the preparation of 4H-chromene derivatives under microwave irradiation from different aromatic aldehydes with a mixture of malononitrile and phenol derivatives were established. The cytotoxic activity of the target compounds was evaluated against four cancer cell lines MCF-7, HCT-116, HepG-2 and A549 in comparison with vinblastine and colchicine as reference drugs. Generally, several compounds showed good cell growth inhibitory activity as compared to standard drugs. The structure–activity relationship studies reported that the substitution at 4- and 6-positions in 4H-chromene nucleus with the specific halogen atom increases the ability of the molecule against the different cell lines. The structures of the synthesized compounds were established on the basis of spectral data, IR, 1H NMR, 13C NMR and MS data.

Halogenated 2-amino-4H-benzo[h]chromene derivatives as antitumor agents and the relationship between lipophilicity and antitumor activity

Several halogenated 2-amino-4H-benzo[h]chromene derivatives were synthesized and evaluated their cytotoxicity. The structures of the synthesized compounds were established on the basis of spectral data. The in vitro antitumor activity of the synthesized compounds against the cell lines MCF-7, HCT-116, and HepG-2 was investigated in comparison with the reference drugs vinblastine, colchicine, and doxorubicin using microculture tetrazolium colorimetric assay. It was found that some halogenated 4H-benzo[h]chromene derivatives showed the highest antitumor activity as compared with the reference drugs. The structure–activity relationship studies reported that the substitution at 4-position in the 4H-benzo[h]chromene nucleus with the specific halogen groups and lipophilicity increases the ability of the molecule against the different cell lines.

Synthesis, in-vitro cytotoxicity of 1H-benzo[f]chromene derivatives and structure–activity relationships of the 1-aryl group and 9-position

Abstract A series of 1H-benzo[f]chromene-2-carbonitriles was synthesized and evaluated for their cytotoxic activities against MCF-7, HCT-116, and HepG-2 cancer cells. The SAR studies reported that the substitution in the phenyl ring at 1-position of 1H-benzo[f]chromene nucleus with the specific group, H atom, or methoxy group at 9-position increases the ability of the molecule against the different cell lines.

Design of New Benzo[h]chromene Derivatives: Antitumor Activities and Structure-Activity Relationships of the 2,3-Positions and Fused Rings at the 2,3-Positions

A series of novel 4H-benzo[h]chromenes 4, 6–11, 13, 14; 7H-benzo[h]chromeno[2,3-d]pyrimidines 15–18, 20, and 14H-benzo[h]chromeno[3,2-e][1,2,4]triazolo[1,5-c]pyrimidine derivatives 19a–e, 24 was prepared. The structures of the synthesized compounds were characterized on the basis of their spectral data. Some of the target compounds were examined for their antiproliferative activity against three cell lines; breast carcinoma (MCF-7), human colon carcinoma (HCT-116) and hepatocellular carcinoma (HepG-2). The cytotoxic behavior has been tested using MTT assay and the inhibitory activity was referenced to three standard anticancer drugs: vinblastine, colchicine and doxorubicin. The bioassays demonstrated that some of the new compounds exerted remarkable inhibitory effects as compared to the standard drugs on the growth of the three tested human tumor cell lines. The structure–activity relationships (SAR) study highlights that the antitumor activity of the target compounds was significantly affected by the lipophilicity of the substituent at 2- or 3- and fused rings at the 2,3-positions.

Halogenated 2-amino-4H-pyrano[3,2-h]quinoline-3-carbonitriles as antitumor agents and structure–activity relationships of the 4-, 6-, and 9-positions

A series of halogenated 2-amino-4-aryl-4H-pyrano[3,2-h]quinoline-3-carbonitrile derivatives were prepared via interaction of 8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, and 8-hydroxy-2-methylquinoline with various α-cyanocinnamonitriles. The assignments of the structure of all synthesized compounds were based on spectral data. The cytotoxic activities of the synthesized compounds against four human tumor cell lines MCF-7, HCT-116, HepG-2, and A549 in comparison with the reference drugs Vinblastine and Colchicine were determined by microculture tetrazolium assay. Several compounds showed significant cytotoxic activity. The structure–activity relationship studies reported that the substitution at 4-, 6-, and 9-positions in several 2-amino-4H-pyrano[3,2-h]quinoline nucleus with the specific halogen atom and lipophilicity increases the ability of the molecule against the different cell lines.

Progress in the chemistry of 5-acetylthiazoles

ABSTRACT This review deals with the synthesis and reactions of 5-acetylthiazoles. Some of these reactions have been used successfully for the production of biologically important compounds. The main purpose of this review is to present a survey of the literature on the chemistry of 5-acetylthiazoles and to provide useful and up-to-date information on their applications because these compounds have not been previously reviewed. GRAPHICAL ABSTRACT