New approaches for the synthesis N-alkylated benzo[b]thiophene derivatives together with their Antiproliferative and molecular docking studies

BACKGROUND

2-Amino thiophene derivatives are important compounds not only for their uses in many heterocyclic reactions but also due to their wide range of pharmaceutical and biological activities.

OBJECTIVE

The aim of this work was to explore a number of new heterocyclic derivatives, studying their inhibitions toward cancer cell lines and studying their structure activity relation ship.

METHOD

Alkylation of 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile was achieved through its reaction with chloroacetone and 2-bromo-1-(4-aryl)ethanone derivatives to give compounds 3 and 11a-c. The produced compoumds were subjected to further heterocylization reactions and cytotoxic evaluation against the three cancer cell lines MCF-7, NCI-H460 and SF-268, together with the normal cell line WI 38. Further evaluations were obtained through studying their inhibitions against cancer cell lines classified according to the disease. Anticancer screening against hepatocellular carcinoma HepG2 and cervical carcinoma HeLa cell lines for all compounds together with the molecular docking of 12c, 12d, 12d and 12f were studied.

RESULTS

Anti-proliferative evaluations and inhibitions for all of the synthesized compounds showed that many compounds exhibited high inhibitions.

CONCLUSION

Toward the three cancer cell lines, compounds 3, 5a, 7a, 9a, 9b, 11b, 12b, 12d, 12e, 12f, 14c, 14e, 14f, 15e, 15f, 16e, 16f, 17c, 18b, 22a and 22c were the most cytotoxic compounds. The high activities of some compounds were attributed to the presence of the electronegative CN and or Cl groups within the molecule. Most of the tested compounds exhibited inhibitions higher than the reference doxorubicin toward hepatocellular carcinoma HepG2 and cervical carcinoma HeLa cell lines. The score of binding energy of compounds 12c, 12d, 12d and 12f was close to the reference Foretinib which appeared through the molecular docking results of such compounds.

Design, synthesis, and cytotoxicity evaluation of novel thiophene, pyrimidine, pyridazine, and pyridine: Griseofulvin heterocyclic extension derivatives

Griseofulvin, an antifungal drug, has also shown good antiproliferative activity previously. This study was aimed to synthesize heterocyclic extension derivatives of griseofulvin and test them against cancer cell lines. Griseofulvin was hydrolyzed to afford griseofulvic acid (1) followed by hybridization with important heterocyclic moieties. Initially, the active methylene group of the 1,3-cyclohexanedione moiety in 1 was utilized to synthesize fused thiophene derivatives (4a and b) by reacting with malononitrile or ethyl cyanoacetate together with elemental sulfur. Compounds 4a and b were further converted to fused pyrimidine derivatives (5a–d) using ethyl isothiocyanate or phenyl isothiocyanate. Compound 1 was also reacted with aryldiazonium chlorides to synthesize compounds 6a and b, which were used to prepare fused thiophene derivatives (7a–d). The resulting thiophenes (7a–d) underwent cyclization to produce fused pyridazine derivatives (8a–d). In addition, fused pyridine derivatives (10a and b) were also prepared by the reaction of 4a and b with ethyl cyanoacetate using two different catalytic bases. The first was triethylamine to form 10a and b in two steps via 9a and b, and the second was sodium ethoxide to afford 10a and b in one step. Finally, 9a and b underwent cyclization in the presence of acetylacetone to yield compounds 11a and b. The structures of synthesized compounds were confirmed using IR, 1H NMR, 13C NMR, and mass spectrometry techniques. The synthesized compounds were subjected to cytotoxic screening against three tumor cell lines and presented good to excellent cytotoxic profiles. Compounds 4a and 11a showed significant inhibitory activity against the three cell lines compared to the standard drug doxorubicin.

New Approaches for the Uses of Cyclohexan-1,4-dione for the Synthesis of 5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-b]pyridine Derivatives used as Potential Anti-prostate Cancer Agents and Pim-1 Kinase Inhibitors

BACKGROUND

Among the wide range of heterocycles, tetrahydrobenzothienopyridine derivatives acquired a special attention due to their wide range of pharmacological activities especially the therapeutic activities. Many pharmacological drugs containing the thiophene nucleus were known in the market.

METHOD

A series of tetrahydrobenzothienopyridine derivatives were synthesized from the reaction of 2-amino- 3-benzoyl-4,5-dihydrobenzo[b]thiophen-6(7H)-one, synthesized and used for further heterocyclization reactions through reaction with different reagents.

RESULTS

Antiproliferative evaluations and c-Met kinase, Pim-1 kinase inhibitions were performed where some compounds revealed high activities.

CONCLUSION

The inhibition of the newly synthesized compounds towards c-Met kinase, the five c-Metdependent cancer cell lines (A549, HT-29, MKN-45, U87MG, and SMMC-7721) and one c-Met-independent cancer cell line (H460) were investigated using foretinib as a standard drug. The results showed that compounds 6b, 7e, 9b, 9e, 16c and 20d were more active than foretinib. Furthermore, compounds 6b, 13b, 16b and 16c were selected to examine their Pim-1 kinase inhibition activity, where compounds 16b and 16c were of high potencies with IC50 values of 0.28 and 0.32 µM, while compounds 6b and 13b were less effective (IC50 > 10 µM).