Cytotoxic activities and morphological studies of thiophene, thiazole and pyridazine derivatives synthesized from benzo[d]thiazole derivatives.

       The benzo[d]thiazole derivatives 4a-c were synthesized and used for the synthesis of thiophene derivatives 6a-f. They form the arylhydrazone derivatives 8a-i which were capable to form pyridazine derivatives 9a-i and 10a-i. The latter compounds reacted with thioglycollic acid to produce the thiazole derivatives 12a-i and 13a-i, respectively.

Novel 5,6,7,8-tetrahydrobenzo[b]pyran Derivatives: Synthesis and Anticancer Activity.

Many new cyclized pyran systems with a potential anti-cancer activity were 13 designed and prepared. Pyran systems showed high reactivity to various chemical 14 reagents. 24 products of the prepared compounds were chosen and tested in (mM) as 15 respectable anticancer factors.

Antiproliferative and Antiprostate Cancer Activities of Heterocyclic Compounds Derived from Cyclohexane-1,4-dione.

2-Amino-6-oxo-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (3) was prepared from the reaction of cyclohexane-1,4-dione with elemental sulfur and malononitrile in 1,4-dioxane and triethylamine as catalyst. The latter compound reacted with triethyl orthoformate and either malononitrile or ethyl cyanoacetate in 1,4-dioxane in the presence of triethylamine to produce 4H-thieno[2,3-f]chromene derivatives 10a,b. In addition, fused pyran and pyridine derivatives were synthesized starting from compound 3.

Synthesis of Fused Quinoline Derivatives With Antiproliferative Activities and Tyrosine Kinases, Pim-1 Kinase Inhibitions.

Cyclohexan-1,3-dione (1) reacted with either 2-aminoprop-1-ene-1,1,3-tricarbonitrile (2a) or diethyl 3-amino-2-cyanopent-2-enedioate (2b) to give the 5,6,7,8-tetrahydronaphthalene derivatives 3a and 3b, respectively. The latter compounds underwent further heterocyclization reactions to give the thieno[2',3':5,6]benzo[1,2-e][1,3]oxazine derivatives. On the other hand, the reaction of compound 1 with trichloroacetonitrile afforded the (2,2,2-trichloroethylidene)cyclohexane derivative 14.

Uses of cyclohexane-1,3-dione for the synthesis of 1,2,4-triazine derivatives as anti-proliferative agents and tyrosine kinases inhibitors.

Tetrahydrobenzo[b]thiophene derivatives were well known to be biologically active compounds and many of them occupy a wide range as anticancer agent drugs. One of our main aim of this work was to synthesize target molecules not only possess anti-tumor activities but also kinase inhibitors. To achieve this goal, our strategy was to synthesize a series of novel 1,2,4-triazines as efficient anticancer drugs with low cytotoxicity and good bioavailability properties using cyclohexane-1,3-dione and 3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene-2-diazonium chloride to give the 2-(2-(2,6-dioxocyclohexylidene)hydrazinyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (3) as the key starting material for many heterocyclization reactions.

The Knoevenagel reaction of cyanoacetylhydrazine with pregnenolone: Synthesis of thiophene, thieno[2,3-d]pyrimidine, 1,2,4-triazole, pyran and pyridine derivatives with anti-inflammatory and anti-ulcer activities.

The reaction of pregnenolone with cyanoacetylhydrazine and ammonium acetate at 120°C gave the Knoevenagel condensation product 3. The latter reacted with different reagents to give thiophene, thieno[2,3-d]pyrimidine, 1,2,4-triazole and pyran derivatives. The anti-inflammatory and anti-ulcer evaluations of the newly synthesized products were evaluated and the results showed that compounds 4, 8c, 10, 11, 13c, 15a, 15c, 17a, 17b, 17e, 18a and 18f possessed higher activity compared to the rest of the compounds.

Uses of 3-(2-Bromoacetyl)-2H-chromen-2-one in the Synthesis of Heterocyclic Compounds Incorporating Coumarin: Synthesis, Characterization and Cytotoxicity.

In this work, 3-bromoacetylcoumarin was used as the key starting material for the synthesis of pyran, pyridine, thiophene, thiazole and pyrazole derivatives through its reaction with different reagents. The structures of the newly synthesized compounds were confirmed on the basis of their spectral data and elemental analyses. All of the synthesized compounds were screened for their in vitro anticancer activity against six human cancer cell lines, namely: human gastric cancer (NUGC), human colon cancer (DLD1), human liver cancer (HA22T and HEPG2), nasopharyngeal carcinoma (HONE1), human breast cancer (MCF) and normal fibroblast cells (WI38).

Synthesis, anti-inflammatory and anti-ulcer evaluations of thiazole, thiophene, pyridine and pyran derivatives derived from androstenedione.

The reaction of androstenedione with bromine gave the 16-bromo derivative 2. The latter reacted with either cyanothioacetamide or thiourea to give the 2-cyanomethylthiazole derivative 4 and the 2-aminothiazole derivative 13. Compound 4 and 13 were used underwent some condensation, coupling and heterocyclization reactions to give thiophene, pyridine and pyran derivatives.

Heterocyclic ring extension of androstenedione: synthesis and cytotoxicity of fused pyran, pyrimidine and thiazole derivatives.

The reaction of androstenedione with either malononitrile or ethyl cyanoacetate and aromatic aldehydes 2a-c gave the pyran derivatives 4a-f, respectively. On the other hand, the reaction of androstenedione with thiourea and the aromatic aldehydes 2a-c gave the pyrimidine derivatives 6a-c, respectively. Compound 6b reacted with 2-bromo-1-arylethanone derivatives 7a-d to give the indeno[2,1-e]thiazole derivatives 8a-d.

Heterocyclic ring extension of estrone: synthesis and cytotoxicity of fused pyran, pyrimidine and thiazole derivatives.

The one pot reaction of estrone with the aromatic aldehydes 2a-c and either of malononitrile or ethyl cyanoacetate afforded the fused pyran derivatives 4a-f. On the other hand, carrying the same reaction using thiourea instead of the cyanomethylene reagent gave the fused pyrimidine derivatives 6a-c. The latter compounds reacted with phenacyl bromide to give the thiazolo[3,2-a]pyrimidine derivatives 8a-c.

The Knoevenagel reactions of pregnenolone with cyanomethylene reagents: synthesis of thiophene, thieno[2,3-b]pyridine, thieno[3,2-d]isoxazole derivatives of pregnenolone and their in vitro cytotoxicity towards tumor and normal cell lines.

The reaction of pregnenolone with either 2-aminoprop-1-ene-1,1,3-tricarbonitrile or 3-oxo-3-phenylpropanenitrile gave the Knoevenagel condensation products 3 and 6, respectively. Separation of the E and Z isomeric compounds of 3 and 6 together with their structure elucidation were carried out. Some chemical transformations of the latter products were carried out and the cytotoxicity of the newly obtained products was evaluated against some cancer cell lines and a human normal cell line.

Reaction of pregnenolone with cyanoacetylhydrazine: novel synthesis of hydrazide-hydrazone, pyrazole, pyridine, thiazole, thiophene derivatives and their cytotoxicity evaluations.

Pregnenolone (1) was used as a template to develop new anticancer compounds. Ring D modification of 1 through its reaction with cyanoacetylhydrazine (2) gave the hydrazide-hydrazone derivative 3. The latter compound underwent heterocyclization reactions to give the pyrazole, pyridine, thiazole and thiophene derivatives of pregnenolone.

Heterocyclizations of pregnenolone: novel synthesis of thiosemicarbazone, thiophene, thiazole, thieno[2,3-b]pyridine derivatives and their cytotoxicity evaluations.

Pregnenolone (1) was used as a template to develop new anticancer compounds. Ring D modification of 1 through its reaction with 4-phenyl-3-thiosemicarbazide gave the thiosemicarbazone derivative 3. The latter compound underwent heterocyclization reactions to give the thiazolyl hydrazonoandrostane and pyrazolyl semicarbazidoandrostane derivatives 5a-d, and 9a-d, respectively.

Uses of cyanoacetylhydrazine in heterocyclic synthesis: novel synthesis of pyrazole derivatives with anti-tumor activities.

The reaction of cyanoacetylhydrazine with chloroacetyl chloride gave N'-(2-chloroacetyl)-2-cyanoacetohydrazide. The latter underwent cyclization to afford 1-(5 amino-3-hydroxy-1H-pyrazol-1-yl)-2-chloroethanone, which underwent nucleophilic substitution to give 3-(5-amino-3-hydroxy-1H-pyrazol-1-yl)-3-oxopropanenitrile. The latter two compounds were used as key synthons to synthesize new thiophene, pyran, thiazole and some fused heterocyclic derivatives.

The reaction of beta-amino-alpha,gamma-dicyanocrotononitrile with acetophenone: synthesis of pyridine, pyridazine and thiophene derivatives with antimicrobial activities.

Condensation of beta-amino-alpha,gamma-dicyanocrotononitrile (1) with acetophenone gave 2-amino-4-phenylpenta-1,3-diene-1,1,3-tricarbonitrile (2). The latter product was used in a series of heterocyclization reactions with different reagents such as diazonium salts, hydrazines, hydroxylamines and elemental sulfur to give pyridazine, pyrazole, isoxazole and thiophene derivatives, respectively. On the other hand, it gave pyridine derivatives with aromatic aldehydes folowed by reaction with cyanomethylene reagents.