Synthesis and Anticancer Properties of Oxazepines Related to Azaisoerianin and IsoCoQuines

In this article, we report the synthesis and biological properties of a series of novel oxazepines related to isoCA-4 having significant antitumor properties. Among them, three oxazepin-9-ol derivatives display a nanomolar or a sub-nanomolar cytotoxicity level against five human cancer cell lines (HCT116, U87, A549, MCF7, and K562). It was demonstrated that the lead compound in this series inhibits tubulin assembly with an IC₅₀ value of 1 μM and totally arrests the cellular cycle in the G2/M phase at the low concentration of 5 nM in HCT116 and K562 cells. Molecular modeling studies perfectly corroborates these promising results.     

Synthesis and Biological Evaluation of CF3Se-Substituted α-Amino Acid Derivatives

Several CF₃Se-substituted α-amino acid derivatives, such as (R)-2-amino-3-((trifluoromethyl)selanyl)propanoates ( 5 a / 6 a ), (S)-2-amino-4-((trifluoromethyl)selanyl)butanoates ( 5 b / 6 b ), (2R,3R)-2-amino-3-((trifluoromethyl)selanyl)butanoates ( 5 c / 6 c ), (R)-2-((S)-2-amino-3-phenylpropanamido)-3-((trifluoromethyl)selanyl)propanoates ( 11 a / 12 a ), and (R)-2-(2-aminoacetamido)-3-((trifluoromethyl)selanyl)propanoates ( 11 b / 12 b ), were readily synthesized from natural amino acids and [Me₄N][SeCF₃]. The primary in vitro cytotoxicity assays revealed that compounds 6 a , 11 a and 12 a were more effective cell growth inhibitors than the other tested CF₃Se-substituted derivatives towards MCF-7, HCT116, and SK-OV-3 cells, with their IC₅₀ values being less than 10 μM for MCF-7 and HCT116 cells. This study indicated the potentials of CF₃Se moiety as a pharmaceutically relevant group in the design and synthesis of novel biologically active molecules.     

Design and Synthesis of DNA‐Interactive β‐Carboline–Oxindole Hybrids as Cytotoxic and Apoptosis‐Inducing Agents

A new series of (E)‐3‐[(1‐aryl‐9H‐pyrido[3,4‐b]indol‐3‐yl)methylene]indolin‐2‐one hybrids were synthesized and evaluated for their in vitro cytotoxic activity against a panel of selected human cancer cell lines, namely, HCT‐15, HCT‐116, A549, NCI‐H460, and MCF‐7, including HFL. Among the tested compounds, (E)‐1‐benzyl‐5‐bromo‐3‐{[1‐(2,5‐dimethoxyphenyl)‐9H‐pyrido[3,4‐b]indol‐3‐yl]methylene}indolin‐2‐one ( 10 s ) showed potent cytotoxicity against HCT‐15 cancer cells with an IC₅₀ value of 1.43±0.26 μm and a GI₅₀ value of 0.89±0.06 μm . Notably, induction of apoptosis by 10 s on the HCT‐15 cell line was characterized by using different staining techniques, such as acridine orange/ethidium bromide (AO/EB) and DAPI. Further, to understand the mechanism of anticancer effects, various assays such as annexin V‐FITC/PI, DCFDA, and JC‐1were performed. The flow cytometric analysis revealed that compound 10 s arrests the HCT‐15 cancer cells at the G0/G1 phase of the cell cycle. Additionally, western blot analysis indicated that treatment of 10 s on HCT‐15 cancer cells led to decreased expression of anti‐apoptotic Bcl‐2 and increased protein expression of both pro‐apoptotic Bax and caspase‐3, ‐8, and ‐9, and cleaved PARP with reference to actin. Next, a clonogenic assay revealed the inhibition of colony formation in HCT‐15 cancer cells by 10 s in a dose‐dependent manner. Moreover, upon testing on normal human lung cells (HFL), the compounds were observed to be safer with a low toxicity profile. In addition, viscosity and molecular‐docking studies showed that compound 10 s has typical intercalation with DNA.     

Anticancer Activity of Electron-Deficient Metal Complexes against Colorectal Cancer in vitro Models

An evaluation of the in vitro cytotoxicity of nine electron-deficient half-sandwich metal complexes towards two colorectal cancer cell lines (HCT116 p53+/+, HCT116 p53−/−) and one normal prostate cell line (PNT2) is presented herein. Three complexes were found to be equally cytotoxic towards both colorectal cancer cell lines, suggesting a p53-independent mechanism of action. These complexes are 12 to 34× more potent than cisplatin against HCT116 p53+/+ and HCT116 p53−/− cells. Furthermore, they were found to exhibit little or no cytotoxicity towards PNT2 normal cells, with selectivity ratios greater than 50. To gain an insight into the potential mechanisms of action of the most active compounds, their effects on the expression levels of a panel of genes were measured using qRT-PCR against treated HCT116 p53+/+ and HCT116 p53−/− cells, and cell-cycle analysis was carried out.     

Sulfonamide Inhibitors of β-Catenin Signaling as Anticancer Agents with Different Output on c-MYC

The Wnt/β-catenin pathway is often found deregulated in cancer. The aberrant accumulation of β-catenin in the cell nucleus results in the development of various malignancies. Specific drugs against this signaling pathway for clinical treatments have not been approved yet. Herein we report inhibitors of β-catenin signaling of potential therapeutic value as anticancer agents. Ethyl 4-((4-(trifluoromethyl)phenyl)sulfonamido)benzoate (compound 14 ) inhibits the effect on Wnt reporter with an IC₅₀ value of 7.0 μM, significantly reduces c-MYC levels, inhibits HCT116 colon cancer cell growth (IC₅₀ 20.2 μM), does not violate Lipinski and Veber rules, and shows predicted Caco-2 and MDCK cell permeability P_app>500 nm s⁻¹. Compound 14 seems to have potential for the development of new anticancer therapies.     

Development of 3‐Phenyl‐N‐(2‐(3‐phenylureido)ethyl)‐thiophene‐2‐sulfonamide Compounds as Inhibitors of Antiapoptotic Bcl‐2 Family Proteins

Antiapoptotic Bcl‐2 family proteins, such as Bcl‐x_L, Bcl‐2, and Mcl‐1, are often overexpressed in tumor cells, which contributes to tumor cell resistance to chemotherapies and radiotherapies. Inhibitors of these proteins thus have potential applications in cancer treatment. We discovered, through structure‐based virtual screening, a lead compound with micromolar binding affinity to Mcl‐1 (inhibition constant (K_i)=3 μM ). It contains a phenyltetrazole and a hydrazinecarbothioamide moiety, and it represents a structural scaffold not observed among known Bcl‐2 inhibitors. This work presents the structural optimization of this lead compound. By following the scaffold‐hopping strategy, we have designed and synthesized a total of 82 compounds in three sets. All of the compounds were evaluated in a fluorescence‐polarization binding assay to measure their binding affinities to Bcl‐x_L, Bcl‐2, and Mcl‐1. Some of the compounds with a 3‐phenylthiophene‐2‐sulfonamide core moiety showed sub‐micromolar binding affinities to Mcl‐1 (K_i=0.3–0.4 μM ) or Bcl‐2 (K_i≈1 μM ). They also showed obvious cytotoxicity on tumor cells (IC₅₀<10 μM ). Two‐dimensional heteronuclear single quantum coherence NMR spectra of three selected compounds, that is, YCW‐E5, YCW‐E10, and YCW‐E11, indicated that they bind to the BH3‐binding groove on Bcl‐x_L in a similar mode to ABT‐737. Several apoptotic assays conducted on HL‐60 cells demonstrated that these compounds are able to induce cell apoptosis through the mitochondrial pathway. We propose that the compounds with the 3‐phenylthiophene‐2‐sulfonamide core moiety are worth further optimization as effective apoptosis inducers with an interesting selectivity towards Mcl‐1 and Bcl‐2.     

Triazolophthalazines: Easily Accessible Compounds with Potent Antitubercular Activity

Tuberculosis (TB) remains one of the major causes of death worldwide, in particular because of the emergence of multidrug‐resistant TB. Herein we explored the potential of an alternative class of molecules as anti‐TB agents. Thus, a series of novel 3‐substituted triazolophthalazines was quickly and easily prepared from commercial hydralazine hydrochloride as starting material and were further evaluated for their antimycobacterial activities and cytotoxicities. Four of the synthesized compounds were found to effectively inhibit the Mycobacterium tuberculosis (M.tb) H₃₇Rv strain with minimum inhibitory concentration (MIC) values <10 μg mL^?1, whereas no compounds displayed cytotoxicity against HCT116 human cell lines (IC₅₀>100 μm ). More remarkably, the most potent compounds proved to be active to a similar extent against various multidrug‐resistant M.tb strains, thus uncovering a mode of action distinct from that of standard antitubercular agents. Overall, their ease of preparation, combined with their attractive antimycobacterial activities, make such triazolophthalazine‐based derivatives promising leads for further development.     

Novel Antitumor L‐Arabinose Derivative of Indolocarbazole with High Affinity to DNA

Novel indolocarbazole derivative 12‐(α‐L ‐arabinopyranosyl)indolo[2,3‐α]pyrrolo[3,4‐c]carbazole‐5,7‐dione (AIC) demonstrated high potency (at submicromolar concentrations) against the NCI panel of human tumor cell lines and transplanted tumors in vivo. In search of tentative targets for AIC, we found that the drug formed high affinity intercalative complexes with d(AT)₂₀, d(GC)₂₀ and calf thymus DNA (binding constants (1.6×10⁶) M ^?1≤K_a≤(3.3×10⁶) M ^?1). The drug intercalated preferentially into GC pairs of the duplex. Importantly, the concentrations at which AIC formed the intercalative complexes with DNA (C≤1 μM ) were identical to the concentrations that triggered p53‐dependent gene reporter transactivation, the replication block, the inhibition of topoisomerase I‐mediated DNA relaxation and death of HCT116 human colon carcinoma cells. We conclude that the formation of high affinity intercalative complexes with DNA is an important factor for anticancer efficacy of AIC.     

Design and Synthesis of Imidazo[2,1‐b]thiazole–Chalcone Conjugates: Microtubule‐Destabilizing Agents

A series of chalcone conjugates featuring the imidazo[2,1‐b]thiazole scaffold was designed, synthesized, and evaluated for their cytotoxic activity against five human cancer cell lines (MCF‐7, A549, HeLa, DU‐145 and HT‐29). These new hybrid molecules have shown promising cytotoxic activity with IC₅₀ values ranging from 0.64 to 30.9 μM . Among them, (E)‐3‐(6‐(4‐fluorophenyl)‐2,3‐bis(4‐methoxyphenyl)imidazo[2,1‐b]thiazol‐5‐yl)‐1‐(pyridin‐2‐yl)prop‐2‐en‐1‐one ( 11 x ) showed potent antiproliferative activity with IC₅₀ values ranging from 0.64 to 1.44 μM in all tested cell lines. To investigate the mechanism of action, the detailed biological aspects of this promising conjugate ( 11 x ) were carried out on the A549 lung cancer cell line. The tubulin polymerization assay and immunofluoresence analysis results suggest that this conjugate effectively inhibits microtubule assembly in A549 cells. Flow cytometric analysis revealed that this conjugate induces cell‐cycle arrest in the G2/M phase and leads to apoptotic cell death. This was further confirmed by Hoechst staining, activation of caspase‐3, DNA fragmentation analysis, and Annexin V–FITC assay. Moreover, molecular docking studies indicated that this conjugate ( 11 x) interacts and binds efficiently with the tubulin protein.     

Design and Synthesis of Aminostilbene–Arylpropenones as Tubulin Polymerization Inhibitors

A series of aminostilbene—arylpropenones were designed and synthesized by Michael addition and were investigated for their cytotoxic activity against various human cancer cell lines. Some of the investigated compounds exhibited significant antiproliferative activity against a panel of 60 human cancer cell lines of the US National Cancer Institute, with 50 % growth inhibition (GI₅₀) values in the range from <0.01 to 19.9 μM . One of the compounds showed a broad spectrum of antiproliferative efficacy on most of the cell lines, with a GI₅₀ value of <0.01 μM . All of the synthesized compounds displayed cytotoxicity against A549 (non‐small‐cell lung cancer), HeLa (cervical carcinoma), MCF‐7 (breast cancer), and HCT116 (colon carcinoma) with 50 % inhibitory concentration (IC₅₀) values ranging from 0.011 to 8.56 μM . A cell cycle assay revealed that these compounds arrested the G2/M phase of the cell cycle. Two compounds exhibited strong inhibitory effects on tubulin assembly with IC₅₀ values of 0.71 and 0.79 μM . Moreover, dot‐blot analysis of cyclin B1 demonstrated that some of the congeners strongly induced cyclin B1 protein levels. Molecular docking studies indicated that these compounds occupy the colchicine binding site of tubulin.     

Antagonism of the Stat3-Stat3 protein dimer with salicylic acid based small molecules

More than 50 new inhibitors of the oncogenic Stat3 protein were identified through a structure–activity relationship (SAR) study based on the previously identified inhibitor S3I‐201 (IC₅₀=86 μM , K_i>300 μM ). A key structural feature of these inhibitors is a salicylic acid moiety, which, by acting as a phosphotyrosine mimetic, is believed to facilitate binding to the Stat3 SH2 domain. Several of the analogues exhibit higher potency than the lead compound in inhibiting Stat3 DNA binding activity, with an in vitro IC₅₀ range of 18.7–51.9 μM , and disruption of Stat3–pTyr peptide interactions with K_i values in the 15.5–41 μM range. One agent in particular exhibited potent inhibition of Stat3 phosphorylation in both breast and multiple myeloma tumor cells, suppressed the expression of Stat3 target genes, and induced antitumor effects in tumor cells harboring activated Stat3 protein.     

Synthesis and Biological Evaluation of Indole‐2‐carbohydrazide Derivatives as Anticancer Agents with Anti‐angiogenic and Antiproliferative Activities

A novel series of indole‐2‐carbohydrazide derivatives were synthesized, characterized, and evaluated for their antiproliferative activities against two cancer cell lines, HCT116 and SW480, and a normal human fetal lung fibroblast cell line, MRC‐5. Among this series, compound 24 f displayed potent cytotoxic activities in vitro against HCT116 and SW480 cell lines with GI₅₀ values of 8.1 and 7.9 μm , respectively, and was inactive against MRC‐5 cells. The newly synthesized compounds were also evaluated for anti‐angiogenesis capabilities by chick chorioallantoic membrane, human umbilical vein endothelial cell (HUVEC) migration, and endothelial microtubule formation assays. Moreover, the effects of 24 f on the vascular endothelial growth factor receptor‐2 and the signaling pathway in HUVECs indicated that this compound inhibits VEGFR‐2 and its downstream related proteins. These results indicate that compound 24 f , as well as the other derivatives, are promising inhibitors of angiogenesis.     

Oxazole‐Bridged Combretastatin A Analogues with Improved Anticancer Properties

Three new oxazole‐bridged combretastatin A analogues with additional functional groups at the B‐ring [‐SMe, ‐OH, p‐quinone] were tested for antiproliferative activity and specificity on human HL‐60 leukemia, 518A2 melanoma, and colon carcinomas HCT‐116 (wt)/(p53^?/?) and HT‐29 cells. While all oxazoles, except quinone 8 , were efficacious against HCT‐116 cells at submicromolar IC₅₀ values (48 h incubation), only thioanisole 5 achieved this potency in combretastatin‐refractory HT‐29 cells by significant upregulation of p21^cip1/waf1 associated with an S/G₂ cell‐cycle arrest.     

Defective Autophagosome Formation in p53-Null Colorectal Cancer Reinforces Crocin-Induced Apoptosis

Crocin, a bioactive molecule of saffron, inhibited proliferation of both HCT116 wild-type and HCT116 p53−/− cell lines at a concentration of 10 mM. Flow cytometric analysis of cell cycle distribution revealed that there was an accumulation of HCT116 wild-type cells in G₁ (55.9%, 56.1%) compared to the control (30.4%) after 24 and 48 h of crocin treatment, respectively. However, crocin induced only mild G2 arrest in HCT116 p53−/− after 24 h. Crocin induced inefficient autophagy in HCT116 p53−/− cells, where crocin induced the formation of LC3-II, which was combined with a decrease in the protein levels of Beclin 1 and Atg7 and no clear p62 degradation. Autophagosome formation was not detected in HCT116 p53−/− after crocin treatment predicting a nonfunctional autophagosome formation. There was a significant increase of p62 after treating the cells with Bafilomycin A1 (Baf) and crocin compared to crocin exposure alone. Annexin V staining showed that Baf-pretreatment enhanced the induction of apoptosis in HCT116 wild-type cells. Baf-exposed HCT116 p53−/− cells did not, however, show any enhancement of apoptosis induction despite an increase in the DNA damage-sensor accumulation, γH2AX indicating that crocin induced an autophagy-independent classical programmed cell death.     

Halogenated Bis(methoxybenzylidene)‐4‐piperidone Curcuminoids with Improved Anticancer Activity

A series of readily available curcuminoids with a halogenated bis(4‐methoxy/4,5‐dimethoxybenzylidene)‐4‐piperidone structure were prepared and analyzed for their cytotoxic impact on eight human cancer cell lines of five different entities. The known 3,4,5‐trimethoxybenzylidene curcuminoid 2 a and the new bis‐(3‐bromophenyl) and bis‐(3,5‐dibromophenyl) derivatives 3 c and 3 d proved to be more strongly antiproliferative than the known curcuminoid EF24 against six of these cell lines. Compounds 2 a and 3 c caused a distinct increase of reactive oxygen species, which eventually elicited apoptosis in 518A2 melanoma cells. Compound 2 a arrested 518A2 melanoma cells in G₁ phase of the cell cycle and had no effect on the expression of pro‐metastatic matrix metalloproteinases MMP‐2 and MMP‐9, whereas 3 c led to an accumulation of 518A2 cells in the G₂/M phase and to a downregulation of MMP‐2 expression. In addition, treatment with 2 a and 3 c resulted in significant inhibition of colony formation in HCT116 cells. Both 2 a and 3 c showed antiangiogenic activity, for example, by inhibiting the formation of sub‐intestinal veins (SIV) in zebrafish embryos. Compound 3 c was also well tolerated by mice and inhibited the growth of HCT116 colon cancer xenografts.     

Modelling and Phenotypic Screening of NAP-6 and 10-Cl-BBQ,AhR Ligands Displaying Selective Breast Cancer Cytotoxicity in Vitro

To exploit the interaction of the aryl hydrocarbon receptor (AhR) pathway in developing breast-cancer-specific cytotoxic compounds, we examined the breast cancer selectivity and the docking pose of the AhR ligands (Z)-2-(2-aminophenyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (NAP-6; 5 ) and 10-chloro-7H-benzo[de]benzo[4,5]imidazo[2,1-a]isoquinolin-7-one (10-Cl-BBQ; 6 ). While the breast cancer selectivity of 5 in vitro is known, we discuss the SAR around this lead and, by using phenotypic cell-line screening and the MTT assay, show for the first time that 6 also presents with breast cancer selectivity, notably in the triple-negative (TN) receptor breast cancer cell line MDA-MB-468, the ER+ breast cancer cell lines T47D, ZR-75-1 and the HER2+ breast cancer cell line SKBR3 (GI₅₀ values of 0.098, 0.97, 0.13 and 0.21 μM, respectively). Indeed, 6 is 55 times more potent in MDA-MB-468 cells than normal MCF10A breast cells (GI₅₀ of 0.098 vs 5.4 μM) and more than 130 times more potent than in cell lines derived from pancreas, brain and prostate (GI₅₀ of 0.098 vs 10–13 μM). Molecular docking poses of 5 and 6 together with analogue synthesis and phenotypic screening show the importance of the naphthalene moiety, and an ortho-disposed substituent on the N-phenyl moiety for biological activity.     

Divergent Synthesis and Evaluation of the in vitro Cytotoxicity Profiles of 3,4-Ethylenedioxythiophenyl-2-propen-1-one Analogues

A new series of 3,4-ethylenedioxythiophene (EDOT)-appended propenones were prepared by condensation reaction and their in vitro cytotoxicity effects were evaluated against five human cancer cell lines. Preliminary structure–activity relationships of EDOT-incorporated 2-propenone derivatives were also established. The EDOT-appended enones demonstrated significant cytotoxicity against human cancer cell lines. The most active analogue, (E)-3-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one ( 3 p , GI₅₀=110 nm ), severely inhibited the clonogenic potential of cancer cells, and induced cell-cycle arrest in the G2/M phase and caused an accumulation of HCT116 colon cancer cells with >4 N DNA content. Also, 3 p exhibited weak inhibition of the enzymatic activity of human topoisomerase I. Molecular docking studies indicated preferential binding of the compounds to the ATP-binding pocket of the human checkpoint 2 kinase (Chk2) catalytic domain, thus, identifying a novel diaryl 2-propenone chemotype for the development of potent inhibitors of Chk2.     

3D‐QSAR‐Assisted Drug Design: Identification of a Potent Quinazoline‐Based Aurora Kinase Inhibitor

We describe the 3D‐QSAR‐assisted design of an Aurora kinase A inhibitor with improved physicochemical properties, in vitro activity, and in vivo pharmacokinetic profiles over those of the initial lead. Three different 3D‐QSAR models were built and validated by using a set of 66 pyrazole (Model I) and furanopyrimidine (Model II) compounds with IC₅₀ values toward Aurora kinase A ranging from 33 nM to 10.5 μM . The best 3D‐QSAR model, Model III, constructed with 24 training set compounds from both series, showed robustness (r²_CV=0.54 and 0.52 for CoMFA and CoMSIA, respectively) and superior predictive capacity for 42 test set compounds (R²_pred=0.52 and 0.67, CoMFA and CoMSIA). Superimposition of CoMFA and CoMSIA Model III over the crystal structure of Aurora kinase A suggests the potential to improve the activity of the ligands by decreasing the steric clash with Val147 and Leu139 and by increasing hydrophobic contact with Leu139 and Gly216 residues in the solvent‐exposed region of the enzyme. Based on these suggestions, the rational redesign of furanopyrimidine 24 (clog P=7.41; Aurora A IC₅₀=43 nM ; HCT‐116 IC₅₀=400 nM ) led to the identification of quinazoline 67 (clog P=5.28; Aurora A IC₅₀=25 nM ; HCT‐116 IC₅₀=23 nM ). Rat in vivo pharmacokinetic studies showed that 67 has better systemic exposure after i.v. administration than 24 , and holds potential for further development.     

Novel Pyridine-Based Hydroxamates and 2′-Aminoanilides as Histone Deacetylase Inhibitors: Biochemical Profile and Anticancer Activity

Starting from the N-hydroxy-3-(4-(2-phenylbutanoyl)amino)phenyl)acrylamide ( 5 b ) previously described by us as a HDAC inhibitor, we prepared four aza-analogues, 6 – 8 , 9 b , as regioisomers containing the pyridine nucleus. Preliminary screening against mHDAC1 highlighted the N-hydroxy-5-(2-(2-phenylbutanoyl)amino)pyridyl)acrylamide ( 9 b ) as the most potent inhibitor. Thus, we further developed both pyridylacrylic- and nicotinic-based hydroxamates ( 9 a , 9 c – f , and 11 a – f ) and 2′-aminoanilides ( 10 a – f and 12 a – f ), related to 9 b , to be tested against HDACs. Among them, the nicotinic hydroxamate 11 d displayed sub-nanomolar potency (IC₅₀: 0.5 nM) and selectivity up to 34 000 times that of HDAC4 and from 100 to 1300 times that of all the other tested HDAC isoforms. The 2′-aminoanilides were class I-selective HDAC inhibitors, generally more potent against HDAC3, with the nicotinic anilide 12 d being the most effective (IC₅₀^HDAC3=0.113 μM). When tested in U937 leukemia cells, the hydroxamates 9 e , 11 c , and 11 d blocked over 80 % of cells in G2/M phase, whereas the anilides did not alter cell-cycle progress. In the same cell line, the hydroxamate 11 c and the anilide 10 b induced about 30 % apoptosis, and the anilide 12 c displayed about 40 % cytodifferentiation. Finally, the most potent compounds in leukemia cells 9 b , 11 c , 10 b , 10 e , and 12 c were also tested in K562, HCT116, and A549 cancer cells, displaying antiproliferative IC₅₀ values at single-digit to sub-micromolar level.     

Synthesis,Cytotoxicity, Induction of Apoptosis,and Interaction with DNA of Dinuclear Platinum(II) Complexes

Six dicarboxylato‐bridged dinuclear platinum(II) complexes S1 – S6 , with a newly designed chiral ligand, 2‐{[(1R,2R)‐2‐aminocyclohexyl]amino}propanoic acid ( HL ), were prepared and spectrally characterized. The in vitro cytotoxicity of all resulting platinum(II) complexes was evaluated against human HCT‐116, MCF‐7, and HepG‐2 tumor cell lines. The results show that all compounds exhibit positive biological activity toward HCT‐116 and MCF‐7 cell lines, of which complexes S3 , S4 , and S5 , with succinate and its derivatives as bridges, showing better activity than the positive controls. Moreover, double‐dyeing flow cytometric resection experiments indicate that the target compounds inhibit tumor cell growth by inducing apoptosis; gel electrophoresis experiments demonstrate the compounds′ ability to prompt pET22b plasmid DNA degradation in almost the same way as oxaliplatin.