Synthesis, topology, molecular docking and dynamics studies of o-phenylenediamine derivative

The N, N'-(1,2-phenylene) bis (1- (4- chlorophenyl) methanimine) (CS4) was synthesized and characterized by infrared (IR), absorption (UV-vis) and NMR (1H and 13C) spectral analyses. The structural parameters, vibrational frequencies, potential energy and the distribution analysis (PED) were calculated by using DFT with the basis set of B3LYP/cc-pVDZ and these spectral values were compared to the experimental values. HOMO and LUMO studied were performed in order to understand the stability and biological activity of the compound. The most reactive sites on the compound were investigated by utilizing MEP energy surface and Fukui function descriptor with the natural population analysis (NPA) of the charges. The study of the natural bond orbitals (NBO) reveals the delocalization of the intramolecular interaction of the charges in the compound. Additionally, topological investigations (ELF, LOL), determination of thermodynamic parameters and noncovalent interaction (NCI) study by using topology (RDG) analysis were also carried out. Finally, the molecular docking and molecular dynamics simulations was carried out by examining against glycosylphosphatidylinositol phospholipase D inhibitor receptor for distinct protein targets (3MZG).Communicated by Ramaswamy H. Sarma.

Pyto-Architechture of Ag, Au and Ag-Au bi-metallic nanoparticles using waste orange peel extract for enable carcinogenic Congo red dye degradation

Ecologically inspired to develop silver, gold and silver/gold bimetallic nanoparticles from discarded orange peel extract. The plant-derived compounds included in discarded orange peel extract have been accountable for the development of Ag, Au and Ag-Au bimetallic nanoparticles, that might be used in the biosynthetic process. The qualitative assessment of developed silver, gold and silver/gold bimetallic nanoparticles has been performed by UV-visible, XRD pattern, FT IR analysis, TEM/HRTEM, EDX and BET isotherm analysis. In this investigation, the photocatalytic effect of developed silver, gold and silver/gold bimetallic nanoparticles on Congo red dye breakdown efficiency was achieved at 96%, 94%, and 99.2%, respectively. Due to prolonged electron-hole recombination process was investigated using UV irradiation and reused for up to 5 consecutive runs without significant loss of photocatalytic activity. Moreover, silver, gold, and silver/gold bimetallic nanoparticles manufactured in an environmentally benign manner could potentially contribute to the ecological cleanup.

Antimicrobial activity prediction, inter- and intramolecular charge transfer investigation, reactivity analysis and molecular docking studies of adenine derivatives

The utilization of the density functional theory (DFT) methodology has developed as a highly efficient method for investigating molecular structure and vibrational spectra, and it is increasingly being employed in various applications relating to biological systems. This study focuses on conducting investigations, both experimental and computed, to analyze the molecular structure, electronic properties and features of (E)-4-(((9H-purin-6-yl)imino)methyl)-2-methoxyphenol (ANVA). The expression ANVA should be rewritten as follows: the compound is a derivative of adenine (primary amine), specifically a vanillin (aldehyde). The present study reports the synthesis, characterization, DFT, docking and antimicrobial activity of ANVA. The optimization of the molecular structure was conducted, and the determination of its structural features was performed using DFT with the B3LYP/cc-pVDZ method. The vibrational assignments were determined in detail by analyzing the potential energy distribution. A strong correlation was observed between the spectra that were observed and the spectra that were calculated. The calculation of intramolecular charge transfer was performed using natural bond orbital analysis. In addition, several computational methods were employed, including highest occupied molecular orbital-least unoccupied molecular orbital analysis, molecular electrostatic potential calculations, non-linear optical, reduced density gradient, localization orbital locator and electron localization function analysis. This paper examines the present use of adenine derivatives in combatting bacterial and fungal infections, as well as the inclusion of spectral and quantum chemical calculations in the discussion.Communicated by Ramaswamy H. Sarma.

Localization of Fluorescent Targets in Deep Tissue With Expanded Beam Illumination for Studies of Cancer and the Brain

Imaging fluorescence through millimeters or centimeters of tissue has important in vivo applications, such as guiding surgery and studying the brain. Often, the important information is the location of one of more optical reporters, rather than the specifics of the local geometry, motivating the need for a localization method that provides this information. We present an optimization approach based on a diffusion model for the fast localization of fluorescent inhomogeneities in deep tissue with expanded beam illumination that simplifies the experiment and the reconstruction. We show that the position of a fluorescent inhomogeneity can be estimated while assuming homogeneous tissue parameters and without having to model the excitation profile, reducing the computational burden and improving the utility of the method. We perform two experiments as a demonstration. First, a tumor in a mouse is localized using a near infrared folate-targeted fluorescent agent (OTL38). This result shows that localization can quickly provide tumor depth information, which could reduce damage to healthy tissue during fluorescence-guided surgery. Second, another near infrared fluorescent agent (ATTO647N) is injected into the brain of a rat, and localized through the intact skull and surface tissue. This result will enable studies of protein aggregation and neuron signaling.

A New Class of β-Pyrrolidino-1,2,3-Triazole Derivatives as β-Adrenergic Receptor Inhibitors: Synthesis, Pharmacological, and Docking Studies

New 1,4-disubstituted β-pyrrolidino-1,2,3-triazoles were synthesized using a reusable copper-iodide-doped neutral alumina catalyst. Synthesis of diversely substituted triazoles and recyclability of CuI catalyst explains the broad scope of this protocol. The synthesized compounds were screened for their antimicrobial and anticancer properties. Most of the compounds showed significant antimicrobial activities against all the tested microorganisms compared to standard drugs. Furthermore, compounds 5a, 5e, 5g, 5h, 5i, and 5j showed moderate to potent activities against A549 and HepG-2 cells. In addition, compounds 5g and 5h displayed potential cytotoxicity activity against A549 cells with IC₅₀ values of 72 ± 3.21 and 58 ± 2.31 µM, respectively. The molecular docking study revealed that some of the synthesized compounds exhibited comparable binding as co-crystalized ligands with the DNA topoisomerase IV and anaplastic lymphoma kinase receptors.

Use of a Single CAR T Cell and Several Bispecific Adapters Facilitates Eradication of Multiple Antigenically Different Solid Tumors

Most solid tumors are comprised of multiple clones that express orthogonal antigens, suggesting that novel strategies must be developed in order to adapt chimeric antigen receptor (CAR) T-cell therapies to treat heterogeneous solid tumors. Here, we utilized a cocktail of low-molecular-weight bispecific adapters, each comprised of fluorescein linked to a different tumor-specific ligand, to bridge between an antifluorescein CAR on the engineered T cell and a unique antigen on the cancer cell. This formation of an immunologic synapse between the CAR T cell and cancer cell enabled use of a single antifluorescein CAR T cell to eradicate a diversity of antigenically different solid tumors implanted concurrently in NSG mice. Based on these data, we suggest that a carefully designed cocktail of bispecific adapters in combination with antifluorescein CAR T cells can overcome tumor antigen escape mechanisms that lead to disease recurrence following many CAR T-cell therapies. SIGNIFICANCE: A cocktail of tumor-targeted bispecific adapters greatly augments CAR T-cell therapies against heterogeneous tumors, highlighting its potential for broader applicability against cancers where standard CAR T-cell therapy has failed.

Carbonic Anhydrase IX-Targeted Near-Infrared Dye for Fluorescence Imaging of Hypoxic Tumors

Use of tumor-targeted fluorescence dyes to help surgeons identify otherwise undetected tumor nodules, decrease the incidence of cancer-positive margins, and facilitate localization of malignant lymph nodes has demonstrated considerable promise for improving cancer debulking surgery. Unfortunately, the repertoire of available tumor-targeted fluorescent dyes does not permit identification of all cancer types, raising the need to develop additional tumor-specific fluorescent dyes to ensure localization of all malignant lesions during cancer surgeries. By comparing the mRNA levels of the hypoxia-induced plasma membrane protein carbonic anhydrase IX (CA IX) in 13 major human cancers with the same mRNA levels in corresponding normal tissues, we document that CA IX constitutes a nearly universal marker for the design of tumor-targeted fluorescent dyes. Motivated by this expression profile, we synthesize two new CA IX-targeted near-infrared (NIR) fluorescent imaging agents and characterize their physical and biological properties both in vitro and in vivo. We report that conjugation of either acetazolamide or 6-aminosaccharin (i.e., two CA-IX-specific ligands) to the NIR fluorescent dye, S0456, via an extended phenolic spacer creates a brightly fluorescent dye that binds CA IX with high affinity and allows rapid visualization of hypoxic regions of solid tumors at depths >1 cm beneath a tissue surface. Taken together, these data suggest that a CA IX-targeted NIR dye can constitute a useful addition to a cocktail of tumor-targeted NIR dyes designed to image all human cancers.

Regio and stereoselective synthesis of anticancer spirooxindolopyrrolidine embedded piperidone heterocyclic hybrids derived from one-pot cascade protocol

Background

Spiropyrrolidine tethered piperidone heterocyclic hybrids were synthesized with complete regio- and stereoselectively in excellent yield via a tandem three-component 1,3-dipolar cycloaddition and subsequent enamine reaction in [bmim]Br. The synthesized compounds were evaluated for their anticancer activity against FaDu hypopharyngeal tumor cells.

Findings

Interestingly, most compounds displayed cytotoxicities similar to the standard anticancer agent bleomycin, with two of them (5a and 5g) being slightly more active than the reference drug.

Conclusion

Synthesized compounds have also been evaluated for their apoptosis-inducing properties in a cancer cell model, finding that treatment with compounds 5a–e led to apoptotic cell death.

Electronic supplementary material

The online version of this article (10.1186/s13065-018-0462-x) contains supplementary material, which is available to authorized users.

Intraoperative Ureter Visualization Using a Novel Near-Infrared Fluorescent Dye

Ureters can be accidentally severed during pelvic surgeries, significantly prolonging the times in the operating room to allow for complete repair of damaged ureters and leading to significant morbidities associated with consequent ureter obstruction and possible kidney dysfunction. In an effort to prevent these complications, light-emitting stents and urine-excreted dyes have been introduced to illuminate the ureter during surgery. However, problems with mechanical insertion, ureter spasm, image contrast, and localized injection have limited interest in their clinical applications. We report here the synthesis and characterization of a new near-infrared (NIR) fluorescent dye (UreterGlow) that can be injected systemically but is excreted primarily through the renal system, allowing ureter imaging with an NIR fluorescence camera. Following intravenous injection of 0.1 mg/kg UreterGlow, we have monitored the flow of UreterGlow through the proximal, medial, and distal segments of the ureter. The timing of ureter visualization was calculated from the time of injection of the drug. The null hypothesis was that "Visualization of the ureter in pigs is possible 60 min after administration of UreterGlow using an NIR camera". UreterGlow displayed excitation and emission maxima of λ_ex = 800 nm and λ_em = 830 nm in phosphate buffered saline, pH 7.4, and could be imaged in the urinary tract in mice. Shortly after injection of UreterGlow into Yorkshire pigs, peristalsis of the ureter could be observed. The distal ureter could be visualized under NIR illumination after 60 min with constant fluorescence in all five pigs for >2 h. The same ureters could not be seen using visible light ( X², p = 0.0001). Because both excitation and emission of UreterGlow occurs at >30 nm longer wavelength than most tumor-imaging fluorescent dyes, it should be possible to distinguish ureter fluorescence from tumor fluorescence with this dye.

Abstract 3571: Use of a universal CAR T cell plus bispecific adapters to eradicate antigenically heterogeneous tumors

Chimeric antigen receptor (CAR) T cell therapies have attracted considerable attention because of their abilities to focus the killing power of T cells specifically onto tumor antigen expressing cancer cells. Despite impressive successes in the clinic, CAR T cell technologies still suffer from an inability to kill cancer cells that mutate to avoid expression of the CAR T cell recognized antigen. While current CAR T cell technologies would require the engineering of a new CAR to recognize a second tumor-specific antigen, we have instead developed a universal CAR that can recognize any tumor antigen. In this modification of standard CAR T cell technology, we fuse an scFv that binds fluorescein to the exoplasmic domain of a T cell receptor that contains the usual 4-1BB and CD3 zeta activation domains within its cytoplasmic domain. We then promote engagement of the resulting CAR T cell with the desired cancer cell by administering a bispecific adapter molecule that contains fluorescein linked to a tumor-specific ligand via a short spacer. Upon addition of this adapter, simultaneous binding of the fluorescein to the CAR and the tumor-specific ligand to the cancer cell mediates multivalent binding of the CAR T cell to the cancer cell. With the simultaneous administration of a cocktail of different tumor-specific adaptors, each comprised of a fluorescein linked to a distinct tumor-specific ligand, multiple orthogonal cancer cells within a heterogeneous solid or liquid tumor can be simultaneously eliminated by a single CAR T cell. To test the ability of our proposed universal CAR T cell to eradicate solid tumors with multiple orthogonal tumor antigens, we first demonstrate the capacity of our anti-fluorescein CAR T cell to kill a variety of cultured human cancer cells in vitro upon addition of the optimal adapter. In this effort, we show that the same anti-fluorescein CAR T cell can kill: i) multiple folate receptor-expressing cancer cells upon addition of folate-fluorescein, ii) PSMA-expressing cancer cells upon addition of a PSMA ligand-fluorescein conjugate, iii) carbonic anhydrase IX-expressing cancer cells upon addition of a CA9 ligand-fluorescein conjugate, and iv) neurokinin-1 receptor expressing cancer cells upon addition of a NK1R ligand-fluorescein conjugate. We then demonstrate that this same universal killing potency is also effective in vivo by transfecting separate MDA-MB-231 breast cancer cell cultures with one of the above tumor antigens and then implanting the MDA-MB-231 cells expressing the orthogonal tumor antigens in NSG mice and showing that our universal CAR T cell can eradicate the resulting tumors upon administration of the appropriate bispecific adapter. Taken together these results establish that a single anti-fluorescein CAR T cell can be exploited to eliminate antigenically heterogeneous tumors upon addition of the correct cocktail of ligand-fluorescein conjugates.

Citation Format: Yong Gu Lee, Isaac Marks, Madduri Srinivasarao, Ananda Kumar Kanduluru, Sakkarapalayam M. Mahalingam, Haiyan Chu, Philip S. Low. Use of a universal CAR T cell plus bispecific adapters to eradicate antigenically heterogeneous tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3571.

Multicomponent Domino Synthesis, Anticancer Activity and Molecular Modeling Simulation of Complex Dispirooxindolopyrrolidines

A series of spirooxindolopyrrolidine fused N-styrylpiperidone heterocyclic hybrids has been synthesized in excellent yield via a domino multicomponent protocol that involves one-pot three component 1,3-dipolar cycloaddition and concomitant enamine reactions performed in an inexpensive ionic liquid, namely 1-butyl-3-methylimidazolium bromide ([bmim]Br). Compounds thus synthesized were evaluated for their cytotoxicity against U-937 tumor cells. Interestingly; compounds 5i and 5m exhibited a better cytotoxicity than the anticancer drug bleomycin. In addition; the effect of the synthesized compounds on the nuclear morphology of U937 FaDu cells revealed that treatment with compounds 5a–m led to their apoptotic cell death.

Evaluation of a Centyrin-Based Near-Infrared Probe for Fluorescence-Guided Surgery of Epidermal Growth Factor Receptor Positive Tumors

Tumor-targeted near-infrared fluorescent dyes have the potential to improve cancer surgery by enabling surgeons to locate and resect more malignant lesions where good visualization tools are required to ensure complete removal of malignant tissue. Although the tumor-targeted fluorescent dyes used in humans to date have been either small organic molecules or high molecular weight antibodies, low molecular weight protein scaffolds have attracted significant attention because they penetrate solid tumors almost as efficiently as small molecules, but can be infinitely mutated to bind almost any antigen. Here we describe the use of a 10 kDa protein scaffold, a Centyrin, to target a near-infrared fluorescent dye to tumors that overexpress the epidermal growth factor receptor (EGFR) for fluorescence-guided surgery (FGS). We have developed and optimized the dose and time required for imaging small tumor burdens with minimal background fluorescence in real-time fluorescence-guided surgery of EGFR-expressing tumor xenografts in murine models. We demonstrate that the Centyrin-near-infrared dye conjugate (CNDC) binds selectively to human EGFR+ cancer cells with an EC50 of 2 nM, localizes to EGFR+ tumor xenografts in athymic nude mice and that uptake of the dye in xenografts is significantly reduced when EGFR are blocked by preinjection of excess unlabeled Centyrin. Taken together, these data suggest that CNDCs can be used for intraoperative identification and surgical removal of EGFR-expressing lesions and that Centyrins targeted to other tumor-specific antigens should prove similarly useful in fluorescence guided surgery of cancer. In addition, we demonstrate that the CNDC is detected in the NIR region of the spectrum and can be utilized for fluorescence-guided surgery (FGS). In addition, we propose that with its eventual complete clearance from EGFR-negative tissues and its quantitative retention in the tumor mass for >24 h, a Centyrin-targeted NIR dye should provide excellent tumor contrast when injected at least 6-8 h before initiation of cancer surgery in human patients.

Design, synthesis and antiproliferative activity of decarbonyl luotonin analogues

A small library of benzimidazole-fused pyrrolo[3,4-b]quinoline has been synthesized from readily available benzimidazole 2-carbaldehyde and various substituted arylamines in good to excellent yields utilizing an intramolecular Povarov reaction catalyzed by boron trifluoride diethyl etharate as the key final step. The compounds thus synthesized can be considered as decarbonyl analogues of the anticancer alkaloid luotonin A and were evaluated in a DNA relaxation assay for their ability to inhibit human topoisomerase I. Interestingly, two of the compounds showed a remarkable activity that is comparable to that of the standard drug camptothecin. The compounds were also evaluated for their cytotoxic effect in four highly aggressive human cancer cell lines, namely KB, MDA-MB231 (breast), LNCap (prostate), and HT1080 (fibrosarcoma). Some of the compounds obtained showed promising cytotoxicities for these four cell lines.

Efficient and Rapid Regioselective Deprotection of Isopropylidene Ketals

A simple and efficient protocol is described for the regioselective hydrolysis of terminal isopropylidene ketal protection in carbohydrate derivatives 1a - 11a. It uses either CoCl2 · 2H2O in acetonitrile or InCl3 in methanol at temperatures ranging from 50 to 60 °C. The low cost of CoCl2·2H2O along with its requirement in catalytic quantities offers a great advantage for the multi-gram scale reaction.

Synthesis of function-oriented 2-phenyl-2H-chromene derivatives using L-pipecolinic acid and substituted guanidine organocatalysts

Organocatalytic domino oxa-Michael/aldol reactions between salicylaldehyde with electron deficient olefins are presented. We screened guanidine, 1,1,3,3-tetramethylguanidine (TMG) and L-pipecolinic acid as organocatalysts for this transformation. 3-Substituted 2-phenyl-2H-chromene derivatives are synthesized with high yields and with poor enantioselectivity (5-17% ee) using L-pipecolinic acid while TMG works well with cinnamaldehyde without using co-catalyst. These 3-substituted-2-phenyl-2H-chromene derivatives are further derivatized to synthesize triazole and biotin-containing chromene derivatives, to facilitate purification of protein targets.

Design and Synthesis of Potential New Apoptosis Agents: Hybrid Compounds Containing Perillyl Alcohol and New Constrained Retinoids

Novel retinoids 1-3 containing perillyl alcohol were synthesized through the addition of perillyl alcohol to the activated carboxylic acids (retinoids) promoted by DCC (N, N'-Dicylohexyl cabodiimide). A set of structurally and functionally diverse perillyl alcohol derivatives of retinoids were obtained in good yields (78-82%). Biological evaluation of these novel hybrid compounds (containing retinoids and perillyl alcohol) is currently underway in our laboratory.

Design and synthesis of novel pinacolylboronate containing combretastatin 'antimitotic agent' analogues

We developed a procedure to synthesize pinacolyl boronate containing stilbene derivatives and used this procedure to synthesize boron-containing combretastatin analogues. The key step involves the Wittig reaction of the ylide 4-(4,4,5,5-tetramethyl-1,3,2-dioxaboratophenyl)-methyl triphenylphosphonium bromide 11 with 3,4,5-trimethoxy benzaldehyde in the presence of (t)BuONa in DMF, providing 88% yield. We are now in a position to evaluate the biological activity of these derivatives as modulators of TGF-beta signaling pathways.

Design and synthesis of (E)-1-((3-ethyl-2,4,4-trimethylcyclohex-2-enylidene)methyl-4-substituted benzenes from 1-(2,6,6-trimethylcyclohex-1-enyl)ethanol

A novel strategy for synthesizing (E)-1-((3-ethyl-2,4,4-trimethylcyclohex-2-enylidene)methyl-4-substituted benzenes from 1-(2,6,6-trimethylcyclohex-1-enyl)ethanol has been developed; the allylic alcohol was treated with PPh(3).HBr in methanol followed by aldehydes in the presence of a base and furnished the 1,3-dienes in moderate to good yields (79-86%).

Propargyl bromide as an excellent alpha-bromoacetone equivalent: convenient and new route to alpha-aroylacetones

[reaction: see text] A variety of alpha-aroylacetones 4a-g have been prepared in excellent yields following a new protocol wherein alpha-aminonitriles 1a-g as the aryl acyl anion equivalents readily react with propargyl bromide as the alpha-bromoacetone equivalent. The alkylated product undergoes one-pot unmasking of the keto functionality along with Markovnikov's hydration of the terminal alkyne with CuSO4 x 5H2O in aqueous methanol at 60 degrees C to furnish the desired target in excellent isolated yields.