New phenothiazine conjugates as apoptosis inducing agents: Design, synthesis, In-vitro anti-cancer screening and 131I-radiolabeling for in-vivo evaluation.

Phenothiazines (PTZs) are a group of compounds characterized by the presence of the 10H-dibenzo-[b,e]-1,4-thiazine system. PTZs used in clinics as antipsychotic drugs with other diverse biological activities. The current aim of the study is to investigate and understand the effect of potent PTZs compounds using a group of In-vitro and In-vivo assays. A total of seventeen novel phenothiazine derivatives have been designed, synthesized, and evaluated primarily in-vitro for their ability to inhibit proliferation activity against NCI-60 cancer cell lines, including several multi-drug resistant (MDR) tumor cell lines. Almost all compounds were active and displayed promising cellular activities with GI50 values in the sub-micromolar range. Four of the most promising derivatives (4b, 4h, 4g and 6e) have been further tested against two selected sensitive cancer cell lines (colon cancer; HCT-116 and breast cancer; MDA-MB231). The apoptosis assay showed that all the selected compounds were able to induce early apoptosis and compound 6e was able to induce additional cellular necrosis. Cell cycle assay showed all selected compounds were able to induce cell cycle arrest at sub-molecular phase of G0-G1 with compound 6e induced cell cycle arrest at G2M in HCT-116 cells. Accordingly, the apoptotic effect of the selected compounds was extensively investigated on genetic level and Casp-3, Casp-9 and Bax gene were up-regulated with down-regulation of Bcl-2 gene suggesting the activation of both intrinsic and extrinsic pathways. In-vivo evaluation of the antitumor activity of compound 4b in solid tumor bearing mice showed promising therapeutic effect with manifestation of dose and time dependent toxic effects at higher doses. For better evaluation of the degree of localization of 4b, its 131I-congener (131I-4b) was injected intravenously in Ehrlich solid tumor bearing mice that showed good localization at tumor site with rapid distribution and clearance from the blood. In-silico study suggested NADPH oxidases (NOXs) as potential molecular target. The compounds introduced in the current study work provided a cutting-edge phenothiazine hybrid scaffold with promising anti-proliferation action that may suggest their anti-cancer activity.

Enhancement of the tail hydrophobic interactions within the carbonic anhydrase IX active site via structural extension: Design and synthesis of novel N-substituted isatins-SLC-0111 hybrids as carbonic anhydrase inhibitors and antitumor agents.

Herein we report the design and synthesis of novel N-substituted isatins-SLC-0111 hybrids (6a-f and 9a-l). A structural extension approach was adopted via N-alkylation and N-benzylation of isatin moiety to enhance the tail hydrophobic interactions within the carbonic anhydrase (CA) IX active site. Thereafter, a hybrid pharmacophore approach was utilized via merging the pharmacophoric elements of isatin and SLC-0111 in a single chemical framework. As planned, a substantial improvement of inhibitory profile of the target hybrids (KIs: 4.7-86.1 nM) towards hCA IX in comparison to N-unsubstituted leads IVa-c (KIs: 192-239 nM), was achieved. Molecular docking of the designed hybrids in CA IX active site unveiled, as planned, the ability of N-alkylated and N-benzylated isatin moieties to accommodate in a wide hydrophobic pocket formed by T73, P75, P76, L91, L123 and A128, establishing strong van der Waals interactions. Hybrid 6c displayed good anti-proliferative activity under hypoxic conditions towards breast cancer MDA-MB-231 and MCF-7 cell lines (IC50 = 7.43 ±â€¯0.28 and 12.90 ±â€¯0.34 µM, respectively). Also, 6c disrupted the MDA-MB-231 cell cycle via alteration of the Sub-G1 phase and arrest of G2-M stage. Additionally, 6c displayed significant increase in the percent of annexinV-FITC positive apoptotic cells from 1.03 to 18.54%. Furthermore, 6c displayed potent VEGFR-2 inhibitory activity (IC50 = 260.64 nM). Collectively, these data suggest 6c as a promising lead molecule for the development of effective anticancer agents.

Novel coumarin-6-sulfonamides as apoptotic anti-proliferative agents: synthesis, in vitro biological evaluation, and QSAR studies.

Herein, we report the synthesis of different novel sets of coumarin-6-sulfonamide derivatives bearing different functionalities (4a, b, 8a-d, 11a-d, 13a, b, and 15a-c), and in vitro evaluation of their growth inhibitory activity towards the proliferation of three cancer cell lines; HepG2 (hepatocellular carcinoma), MCF-7 (breast cancer), and Caco-2 (colon cancer). HepG2 cells were the most sensitive cells to the influence of the target coumarins. Compounds 13a and 15a emerged as the most active members against HepG2 cells (IC50 = 3.48 ± 0.28 and 5.03 ± 0.39 µM, respectively). Compounds 13a and 15a were able to induce apoptosis in HepG2 cells, as assured by the upregulation of the Bax and downregulation of the Bcl-2, besides boosting caspase-3 levels. Besides, compound 13a induced a significant increase in the percentage of cells at Pre-G1 by 6.4-folds, with concurrent significant arrest in the G2-M phase by 5.4-folds compared to control. Also, 13a displayed significant increase in the percentage of annexin V-FITC positive apoptotic cells from 1.75-13.76%. Moreover, QSAR models were established to explore the structural requirements controlling the anti-proliferative activities.

Salmeterol Xinafoate.

Salmeterol xinafoate is a potent and a long-acting ß2-adrenoceptor agonist. It is prescribed for the treatment of severe persistent asthma and chronic obstructive pulmonary disease. Different methods were used to prepare (R)-(-)-salmeterol such as: mixing a sample of 4-benzyloxy-3-hydroxymethyl-ω-bromoacetophenone with sodium lauryl sulfate and the mixture was added to the microbial culture of Rhodotorula rubra, treatment of p-hydroxyacetophenone with Eschenmoser's salt and carbonate exchange resin followed by a sequence of supported reagents and scavenging agents or via Rh-catalyzed asymmetric transfer hydrogenation. The enantioselective synthesis of (S)-salmeterol was achieved via asymmetric reduction of the azidoketone 4 by Pichia angusta yeast. Physical characteristics of salmeterol xinafoate were confirmed via: X-ray powder diffraction pattern, thermal analysis and UV, vibrational, nuclear magnetic resonance, and mass spectroscopical data. Initial improvement in asthma control may occur within 30 min following oral inhalation of salmeterol in fixed combination with fluticasone propionate. Clinically important improvements are maintained for up to 12 h in most patients. It is extensively metabolized in the liver by hydroxylation, thus increased plasma concentrations may occur in patients with hepatic impairment.