Screening identified 2‐hydroxy‐3‐oxo‐3,4‐dihydro‐2 H ‐benzo[ b ][1,4]oxazine‐6‐carboxylic acid ( 1 ) as a 55 µM dynaminGTPase inhibitor. Synthesis of three 1 ‐based libraries shows no potency enhancement. However, S‐isostere‐based 3‐oxo‐3,4‐dihydro‐2 H ‐benzo[ b ][1,4]thiazine‐6‐carboxylic acid ( 16 ) gives rise to Libraries 4–6. Library 4 retains the C6‐ester of 1 ; only H‐bond capable analogs (–OH, –CO 2 H) improves dynamin inhibition (IC 50 < 20 µM), with C3′‐CO 2 H 17j returning an IC 50 = 1.3 ± 0.5 µM. N ‐methylation gives Library 5 and essentially removes activity. Most (>80%) of Library 6 analogs are dynamin active. Highest potency is noted with H‐bond‐accepting aromatic moieties: C3′‐OAc 19p , C2′,C3′,C4′‐tri‐OAc 19r, and C3′,C4′‐di‐OMe 19y (IC 50 values of 5.1, 5.2 and 7.2 µM, respectively). A N,N ‐dimethylaminopropyl chain enhances activity with C4′‐OH 19u to 21 , but has no effect with C4′‐OH 17u to 20 . This may be due to compound remodeling within the active site to best align two of the three H‐bond‐donating groups (of 19u vs. 17u ). There appears to be a minimum requirement of two H‐bond donors. Combined this work has identified seven new analogs: C3′–CO 2 H 17j , C2′–OH 17s , C3′,C4′‐di‐OMe 18y , C3′‐OAc 19p , C2′,C3′,C4′‐tri‐OAC 19r , C3′,C4′‐di‐OMe 19y, and C4′‐O(CH 2 ) 3 NMe 2 21 with dynamin IC 50 values of 1.3–10.0 µM. 118 compounds aresynthesized and screened.

Lemon-scented tea tree (Leptospermum petersonii, Myrtaceae family) has been traditionally used as both bush food and medicine by Australian Aboriginal people. However, its key individual phytochemicals and therapeutic potential are not well characterised. The study investigated major phytochemicals and evaluated the anti-diabetic, anti-Alzheimer's, and anti-pancreatic cancer potential of L. petersonii extract and its fractions. The fraction was carried out based on the retention time by using HPLC. Major phytochemicals were identified using LC-QTOF-MS and HPLC. Total phenolic content and antioxidant activity were determined using Folin-Ciocalteu, DPPH, ABTS, and FRAP assays. In vitro assays, including alpha-glucosidase, alpha-amylase, acetylcholinesterase inhibition, and MTT cytotoxicity tests, were used to assess anti-diabetic, anti-Alzheimer's, and anti-pancreatic cancer potential, respectively. As a result, six phenolic acids, ten flavonoids, two phenols, and four triterpenoids were identified. The crude extract showed high phenolic content (96 mg GAE/g DW), abundant terpenoids (302 mg EE/g DW), and strong antioxidant activity. Fractionation of the crude extract produced four fractions with significantly enhanced bioactive properties. Fraction 1 (F1) exhibited the highest phenolic content and antioxidant capacity, and over 3-fold stronger alpha-glucosidase inhibition compared to the crude extract. Fraction 3 (F3) showed 10-fold greater acetylcholinesterase inhibition, while Fraction 4 (F4) demonstrated a 20-fold stronger inhibitory effect on pancreatic cancer cell growth, including AsPC-1, BxPC-3, Capan-2, HPAC, MiaPaCa2, PANC-1 (p < 0.05). These findings highlight L. petersonii as a promising source of bioactive compounds with potential therapeutic applications.

Six platinum(IV) prodrugs incorporating 5-fluorouracil (5FU) derivatives in the axial positions were synthesised, purified, fully characterised, and their biological activity assessed. The 5FU derivatives, 5FU-acetate and 5FU-methoxybutanoate, were successfully coordinated to [Pt(PL)(1S,2S-diaminocyclohexane)(OH)₂]2+ scaffolds, where PL = 1,10-phenanthroline (Phen) or 5,6-dimethyl-1,10-phenanthroline (56Me₂Phen). All complexes exhibited exceptional in vitro cytotoxicity across a broad panel of cancer cell lines, with [PtIV(56Me2Phen)(1S,2S-diaminocyclohexane)(5FU-methoxybutanoate)(OH)](NO3)2 (6) demonstrating the lowest GI₅₀ of 1 nM against the prostate Du145 cancer cell line. Each complex displayed significantly enhanced activity compared to cisplatin, with 6 being up to 1400-fold more active in selected cancer cell lines. Complexes incorporating the 5FU-methoxybutanoate ligand (5 and 6) were notably more cytotoxic and lipophilic than their 5FU-acetate analogues (1-3), with 6 also exhibiting ∼2-fold greater potency than its platinum(II) precursor. Further studies in the HT29 colon cancer cell line revealed that 5 and 6 induced sustained elevations in reactive oxygen species (ROS) and substantial reductions in mitochondrial membrane potential, indicating that oxidative stress and mitochondrial dysfunction contributed to their cytotoxicity. Collectively, these findings demonstrate that the incorporation of 5FU into platinum(IV) prodrugs enhances both potency and mechanistic activity, with prodrug 6 emerging as a highly promising anticancer candidate.

With global cancer cases and their associated costs steadily increasing, there is an imperative for sustained research efforts to improve health outcomes and mitigate its socio-economic impact. Several treatments have been developed over the last few decades to alleviate these issues. Among them, platinum(ii) and(iv)(Pt(ii) and(iv)) heteroleptic complexes show promise in the field of cancer treatment. However, the design of innovative derivatives towards enhanced cancer therapies is hindered by the limited number of synthetic methods currently available. Mechanochemistry is rapidly emerging as a powerful alternative to traditional synthetic routes. In this context, it not only offers a fast, efficient and scalable synthesis with a reduced environmental footprint but also renders a new conceptual synthetic framework in materials science and pharmaceuticals. Herein, we demonstrate proof-of-concept that Pt(ii) heteroleptic complexes can be readily synthesised using a solvent-free milling and kneading mechanochemical method. Using PHENSS as an example, the synthesis was readily scaled up by 6.7-fold, whilst maintaining high yield and purity. The newly developed method significantly reduced reaction time by 8-fold and energy consumption by 28.8-fold, in comparison to the traditional route. Further, the environmental footprint was notably reduced when mechanochemistry was employed (i.e., similar to 700-fold reduction in the environmental factor (E-factor) and similar to 200-fold in the process mass intensity (PMI)). This work also determined that the mechanochemical method did not alter the in vitro growth inhibition activity. This study provides new insights into the mechanochemical synthesis of six Pt(ii) heteroleptic complexes: PHENSS, 56MESS, 47MESS, 4MESS, 3478MESS and 5ClSS, and sets the foundation for scalable and sustainable routes towards heteroleptic metal complexes with potential applications across diverse fields.

Background: The synthesis and biological investigation of pyrrolidine (L-gulo) iminosugars bearing an organic boron pharmacophore in ortho and meta positions of an N-benzyl group is reported. This paper completes the structure–activity relationship data for this novel family of boron-bearing iminosugars. These can establish reversible intramolecular interactions via dative bonding from nucleophilic amino acid side chains to the empty p-orbital of the boron atom. Methods: Inhibitory activities against two panels of glycosidases and cancer cell lines were investigated to ascertain structure–activity relationship profiles for these novel iminosugar drug leads. Results: These iminosugars display selective, moderate-to-weak inhibitions (IC50s = 116–617 μM) of β-D-galactosidase (bovine liver), and indications of inhibition of β-D-glucosidases (almond, bovine liver) (IC50s = 633 and 710 μM) and α-D-glucosidases (rice, yeast, rat intestinal maltase) (IC50s = 106–784 μM). The boronic acid group emerges as a useful pharmacophore for management of lysosomal storage disorders via the chaperone-mediated therapy approach. The cancer assays revealed that the A2780 ovarian carcinoma cell line is selectively inhibited by all compounds screened and the MIA-Pa-Ca2 pancreatic carcinoma cell line is selectively inhibited by most compounds. Growth inhibition and GI50 values were most potent for the meta 7 side-product. Conclusions: Beyond the cancer cell line inhibition and dose-response capabilities, the real therapeutic potential of these borylated drugs lies in their switch on/switch off activation under boron neutron capture therapy (BNCT) radiotherapeutic conditions, thus providing an important area of application for borylated monosaccharides.

Established methods for conjugating biomolecules to non-conventional complexes such as [Pt(1,10-phenanthroline)(1S,2S-diamminocyclohexane)(OH)2]2+ (PtIVPhenSS) are limited in scope. To address this, we investigated amide, ester, and carbamate strategies, however we encountered significant issues with stability and thus yield. To overcome these shortcomings, we examined an imine linking strategy, using hydrazone and oxime ligation, which proved to be rapid and effective. Here we detail the synthesis of seven platinum(IV) complexes derived from PtIVPhenSS which demonstrate the suitability of an imine conjugation method as a potential linking strategy. Furthermore, we tested these complexes in broad panel of cancer cell lines, identifying that this strategy did not diminish the biological activity of the complex.

Background/Objectives: This article reports pyrrolidine iminosugars of L-gulose absolute stereochemical configuration that are functionalised via N-alkylation to bear boronate ester and boronic acid pharmacophores. Inclusion of boron pharmacophores has been shown to reduce toxicity profiles of drugs and can expand the range of interactions between drugs and target enzymes. Methods: The synthetic development, detailed spectroscopic analysis, and biological investigation against glycosidase enzymes and cancer cell lines of these novel five-membered ring iminosugars are reported. Results: This family of iminosugars displays selective, moderate-to-weak inhibition (IC50s = 133–501 μM) of β-d-galactosidase (bovine liver) and emerging inhibition of β-d-glucosidases (almond) and (bovine liver). The boronic acid pharmacophore may be suitable for the management of lysosomal storage disorders to support the restoration of biological activity of mutant enzymes via the chaperone-mediated therapy approach. From a structure–activity perspective, the cancer screening revealed slight growth inhibition in a panel of cancer cell lines, with A2780 ovarian carcinoma cells showing the strongest response across all compounds. Beyond the growth inhibition capabilities, the real therapeutic potential of these borylated drugs lies in their switch-on/switch-off activation under BNCT radiotherapeutic conditions. Conclusions: This is an important novel family of drug leads capable of interacting with drug targets via intermolecular and intramolecular interactions, changing shape and electronics. Introduction of organic boron atoms to organic molecules presents significant synthetic and purification challenges, as well as analysis of the equilibria that arise in aqueous systems. We provide a methodology to achieve all this and introduce boron pharmacophores onto carbohydrate scaffolds in a systematic manner to facilitate a more widespread adoption of boron pharmacophores.

Screening identified 2-hydroxy-3-oxo-3,4-dihydro-2H-benzo[b][1,4]oxazine-6-carboxylic acid (1) as a 55 µM dynaminGTPase inhibitor. Synthesis of three 1-based libraries shows no potency enhancement. However, S-isostere-based 3-oxo-3,4-dihydro-2H-benzo[b][1,4]thiazine-6-carboxylic acid (16) gives rise to Libraries 4-6. Library 4 retains the C6-ester of 1; only H-bond capable analogs (-OH, -CO2H) improves dynamin inhibition (IC50 < 20 µM), with C3'-CO2H 17j returning an IC50 = 1.3 ± 0.5 µM. N-methylation gives Library 5 and essentially removes activity. Most (>80%) of Library 6 analogs are dynamin active. Highest potency is noted with H-bond-accepting aromatic moieties: C3'-OAc 19p, C2',C3',C4'-tri-OAc 19r, and C3',C4'-di-OMe 19y (IC50 values of 5.1, 5.2 and 7.2 µM, respectively). A N,N-dimethylaminopropyl chain enhances activity with C4'-OH 19u to 21, but has no effect with C4'-OH 17u to 20. This may be due to compound remodeling within the active site to best align two of the three H-bond-donating groups (of 19u vs. 17u). There appears to be a minimum requirement of two H-bond donors. Combined this work has identified seven new analogs: C3'-CO2H 17j, C2'-OH 17s, C3',C4'-di-OMe 18y, C3'-OAc 19p, C2',C3',C4'-tri-OAC 19r, C3',C4'-di-OMe 19y, and C4'-O(CH2)3NMe2 21 with dynamin IC50 values of 1.3-10.0 µM. 118 compounds aresynthesized and screened.

Twenty‐five chimera compounds of Pitstop® 1 and 2 were synthesised and screened for their ability to block the clathrin terminal domain‐amphiphysin protein‐protein interaction (NTD‐PPI using an ELISA) and clathrin mediated endocytosis (CME) in cells. Library 1 was based on Pitstop 2, but no notable clathrin PPI or in‐cell activity was observed. With the Pitstop 1, 16 analogues were produced with 1,8‐naphthalic imide core as a foundation. Analogues with methylene spaced linkers and simple amides showed a modest to good range of PPI inhibition (7.6 to 42.5 mM, naphthyl 39 and 4‐nitrophenyl 40 respectively) activity. These data reveal the importance of the naphthalene sulfonate moiety, with no des‐SO3 analogue displaying PPI inhibition. This was consistent with the observed analogue docked poses within the clathrin terminal domain Site 1 binding pocket. Further modifications targeted the naphthalene imide moiety, with the installation of 5‐Br (45a), 5‐OH (45c) and 5‐propyl ether (45d) moieties. Among them, the OH 45c and propyl ether 45d retained PPI inhibition, with propyl ether 45d being the most active with a PPI inhibition IC50 = 7.3 mM. This is 2x more potent than Pitstop® 2 and 3x more potent than Pitstop 1.

Simple synthesis, binds and inhibits tubulin, and potent broad-spectrum cytotoxicity.

We previously reported on the interaction of 10-chloro-7H-benzo[de]benzo[4,5]imidazo[2,1-a]isoquinolin-7-one (10-Cl-BBQ) with the Aryl hydrocarbon Receptor (AhR) and selective growth inhibition in breast cancer cell lines. We now report on a library of BBQ analogues with substituents on the phenyl and naphthyl rings for biological screening. Herein, we show that absence of the phenyl Cl of 10-Cl-BBQ to produce the simple BBQ molecule substantially enhanced the growth inhibitory effect with GI50 values of 0.001–2.1 μM in select breast cancer cell lines MCF-7, T47D, ZR-75-1, SKBR3, MDA-MB-468, BT20, BT474 cells, while having modest effects of 2.1–7 μM in other cell lines including HT29, U87, SJ-G2, A2780, DU145, BE2-C, MIA, MDA-MB-231 or normal breast cells, MCF10A (3.2 μM). The most potent growth inhibitory effect of BBQ was observed in the triple negative cell line, MDA-MB-468 with a GI50 value of 0.001 μM, presenting a 3,200-fold greater response than in the normal MCF10A breast cells. Additions of Cl, CH3, CN to the phenyl ring and ring expansion from benzoimidazole to dihydroquinazoline hindered the growth inhibitory potency of the BBQ analogues by blocking potential sites of CYP1 oxidative metabolism, while addition of Cl or NO2 to the naphthyl rings restored potency. In a cell-based reporter assay all analogues induced 1.2 to 10-fold AhR transcription activation. Gene expression analysis confirmed the induction of CYP1 oxygenases by BBQ. The CYP1 inhibitor α-naphthoflavone, and the SULT1A1 inhibitor quercetin significantly reduced the growth inhibitory effect of BBQ, confirming the importance of both phase I and II metabolic activation for growth inhibition. Conventional molecular modelling/docking revealed no significant differences between the binding poses of the most and least active analogues. More detailed DFT analysis at the DSD-PBEP86/Def-TZVPP level of theory could not identify significant geometric or electronic changes which would account for this varied AhR activation. Generation of Fukui functions at the same level of theory showed that CYP1 metabolism will primarily occur at the phenyl head group of the analogues, and substituents within this ring lead to lower cytotoxicity.

Kinetically inert platinum(IV) complexes are a chemical strategy to overcome the impediments of standard platinum(II) antineoplastic drugs like cisplatin, oxaliplatin and carboplatin. In this study, we reported the syntheses and structural characterisation of three platinum(IV) complexes that incorporate 5-benzyloxyindole-3-acetic acid, a bioactive ligand that integrates an indole pharmacophore. The purity and chemical structures of the resultant complexes, P-5B3A, 5-5B3A and 56-5B3A were confirmed via spectroscopic means. The complexes were evaluated for anticancer activity against multiple human cell lines. All complexes proved to be considerably more active than cisplatin, oxaliplatin and carboplatin in most cell lines tested. Remarkably, 56-5B3A demonstrated the greatest anticancer activity, displaying GI50 values between 1.2 and 150 nM. Enhanced production of reactive oxygen species paired with the decline in mitochondrial activity as well as inhibition of histone deacetylase were also demonstrated by the complexes in HT29 colon cells.

Cancer poses a significant threat to global health and new treatments are required to improve the prognosis for patients. Previously, unconventional platinum complexes designed to incorporate polypyridyl ligands paired with diaminocyclohexane have demonstrated anticancer activity in KRAS mutated cells, previously thought to be undruggable and have cytotoxicity values up to 100 times better than cisplatin. In this work, these complexes were used as inspiration to design six novel cyclometallated examples, whose fluorescence could be exploited to better understand the mechanism of action of these kinds of platinum drugs. The cytotoxicity results revealed that these cyclometallated complexes (CMCs) have significantly different activity compared to the complexes that inspired them; they are as cytotoxic as cisplatin and have much higher selectivity indices in breast cancer cell lines (MCF10A/MCF-7). Complexes 1b, 2a, and 3b all had very high selectivity indexes compared to previous Pt(II) complexes. This prompted further investigation into their DNA binding properties, which revealed that they had good affinity to ctDNA, especially CMCs 1a and 3b. Their inherent fluorescence was successfully utilised in the calculation of their DNA binding affinity and could be useful in future work.

Supplementary Figures 1-5 and Legends from The Dynamin Inhibitors MiTMAB and OcTMAB Induce Cytokinesis Failure and Inhibit Cell Proliferation in Human Cancer Cells

Supplementary Video 1 from The Dynamin Inhibitors MiTMAB and OcTMAB Induce Cytokinesis Failure and Inhibit Cell Proliferation in Human Cancer Cells

Cisplatin-type covalent chemotherapeutics are a cornerstone of modern medicinal oncology. However, these drugs remain encumbered with dose-limiting side effects and are susceptible to innate and acquired resistance. The bulk of platinum anticancer research has focused on Cisplatin and its derivatives. Here, we take inspiration from the design of platinum complexes and ligands used successfully with other metals to create six novel complexes. Herein, the synthesis, characterization, DNA binding affinities, and lipophilicity of a series of non-traditional organometallic Pt(II)-complexes are described. These complexes have a basic [Pt(PL)(AL)]Cl2 molecular formula which incorporates either 2-pyrrolidin-2-ylpyridine, 2-(1H-Imidazol-2-yl)pyridine, or 2-(2-pyridyl)benzimidazole as the PL; the AL is resolved diaminocyclohexane. Precursor [Pt(PL)(Cl)2] complexes were also characterized for comparison. While the cytotoxicity and DNA binding properties of the three precursors were unexceptional, the corresponding [Pt(PL)(AL)]2+ complexes were promising; they exhibited different DNA binding interactions compared with Cisplatin but with similar, if not slightly better, cytotoxicity results. Complexes with 2-pyrrolidin-2-ylpyridine or 2-(2-pyridyl)benzimidazole ligands had similar DNA binding properties to those with 2-(1H-Imidazol-2-yl)pyridine ligands but were not as cytotoxic to all cell lines. The variation in activity between cell lines was remarkable and resulted in significant selectivity indices in MCF10A and MCF-7 breast cancer cell lines, compared with previously described similar Pt(II) complexes such as 56MESS.

Developing new and versatile platinum(IV) complexes that incorporate bioactive moieties is a rapidly evolving research strategy for cancer drug discovery. In this study, six platinum(IV) complexes (1–6) that are mono-substituted in the axial position with a non-steroidal anti-inflammatory molecule, naproxen or acemetacin, were synthesised. A combination of spectroscopic and spectrometric techniques confirmed the composition and homogeneity of 1–6. The antitumour potential of the resultant complexes was assessed on multiple cell lines and proved to be significantly improved compared with cisplatin, oxaliplatin and carboplatin. The platinum(IV) derivatives conjugated with acemetacin (5 and 6) were determined to be the most biologically potent, demonstrating GI50 values ranging between 0.22 and 250 nM. Remarkably, in the Du145 prostate cell line, 6 elicited a GI50 value of 0.22 nM, which is 5450-fold more potent than cisplatin. A progressive decrease in reactive oxygen species and mitochondrial activity was observed for 1–6 in the HT29 colon cell line, up to 72 h. The inhibition of the cyclooxygenase-2 enzyme was also demonstrated by the complexes, confirming that these platinum(IV) complexes may reduce COX-2-dependent inflammation and cancer cell resistance to chemotherapy.

Supplementary Video 2 from The Dynamin Inhibitors MiTMAB and OcTMAB Induce Cytokinesis Failure and Inhibit Cell Proliferation in Human Cancer Cells